258 results on '"home-range"'
Search Results
2. Nearby night lighting, rather than sky glow, is associated with habitat selection by a top predator in human-dominated landscapes.
- Author
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Barrientos, Rafael, Vickers, Winston, Abelson, Eric, Dellinger, Justin, Waetjen, David, Fandos, Guillermo, Shilling, Fraser, and Longcore, Travis
- Subjects
ALAN ,Puma concolor ,home-range ,natural illumination ,visible and infrared imaging radiometer suite ,zenith brightness ,Animals ,Humans ,Puma ,Lighting ,Environmental Pollution ,Ecosystem ,Environment - Abstract
Artificial light at night (ALAN) is increasing in extent and intensity across the globe. It has been shown to interfere with animal sensory systems, orientation and distribution, with the potential to cause significant ecological impacts. We analysed the locations of 102 mountain lions (Puma concolor) in a light-polluted region in California. We modelled their distribution relative to environmental and human-disturbance variables, including upward radiance (nearby lights), zenith brightness (sky glow) and natural illumination from moonlight. We found that mountain lion probability of presence was highly related to upward radiance, that is, related to lights within approximately 500 m. Despite a general pattern of avoidance of locations with high upward radiance, there were large differences in degree of avoidance among individuals. The amount of light from artificial sky glow was not influential when included together with upward radiance in the models, and illumination from moonlight was not influential at all. Our results suggest that changes in visibility associated with lunar cycles and sky glow are less important for mountain lions in their selection of light landscapes than avoiding potential interactions with humans represented by the presence of nearby lights on the ground. This article is part of the theme issue Light pollution in complex ecological systems.
- Published
- 2023
3. Using juvenile movements as a proxy for adult habitat and space use in long‐lived territorial species: a case study on the golden eagle.
- Author
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Hemery, Arzhela, Duriez, Olivier, Itty, Christian, Henry, Pierre‐Yves, and Besnard, Aurélien
- Subjects
- *
GOLDEN eagle , *WILDLIFE conservation , *ADULTS , *LAND cover , *SPECIES , *HABITAT selection , *PUBLIC spaces - Abstract
Effective conservation management of wildlife species depends on understanding their space and habitat use. Telemetry has become the primary source of data for information on how species use space and habitats. However, animals can be difficult to capture, leading to limited sample sizes and thus low quality inferences. As some individuals may be easier to capture than others, it may be tempting to use them to make inferences about the studied population as a whole. Juvenile birds, in contrast to adults, are easy to capture while they are still in the nest. However, there are few studies on when and how they might serve to obtain a representative characterization of the habitat or space use of adults. This study investigated this by using GPS‐tracking data of 35 adult/juvenile dyads of golden eagles Aquila chrysaetos, with the juvenile and adult in a dyad sharing the same home‐range. We assessed juvenile‐to‐adult home‐range overlap and also compared their relative use of habitats within that space. We also analysed how these metrics evolved throughout the post‐fledging dependence period (PFDP). During this period, juvenile‐to‐adult similarity was more than 80% for the entire home‐range, whereas it was lower for the core area (approximately 60%). Habitat‐use similarity was high, at approximately 90% for both the home‐range and core area, both in land‐cover and topography. The similarity increased following the improvement of juvenile flight skills over a period of two months, to the extent that two months after fledging and until the end of the PFDP, habitat and space use of juveniles can be used to infer the home‐range and habitat requirements of adults. It would be valuable to study this 'adult‐by‐juvenile replacement' approach in other species to determine whether it could be generalized, notably for species with a shorter dependence period or more complex social interactions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Individual variation in home‐range across an ocean basin and links to habitat quality and management.
- Author
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Hays, Graeme C., Rattray, Alex, Shimada, Takahiro, and Esteban, Nicole
- Subjects
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GREEN turtle , *SEAGRASS restoration , *OVERGRAZING , *SEAGRASSES , *BODY size , *ECOSYSTEM health , *CULLING of animals , *HABITAT selection , *TURTLE populations - Abstract
Overgrazing may lead to management intervention (e.g. culling, animal relocation) to try and prevent habitat destruction. Overgrazing leading to seagrass meadow collapse has been recorded for green turtles (Chelonia mydas) at several sites around the world, although the generality of this phenomenon and the need for intervention to prevent widespread seagrass destruction is unknown.Where turtles have degraded seagrass meadows, home‐ranges are expected to be large and turtles will relocate as meadows are destroyed. We used high resolution Fastloc GPS tracking (n = 32 individuals, mean = 171 days per individual, SD = 99) to record the home‐range of adult green turtles at foraging sites spanning 4523 km of longitude across the Western Indian Ocean. Contrary to predictions if overgrazing was occurring, we recorded small home‐ranges and turtles rarely relocated their daytime foraging areas.Based on all locations received, the mean 50% and 95% utilisation distributions (UD50 and UD95) were 2.4 km2 (SD = 2.7) and 15.4 km2 (SD = 17.7). Space use was often particularly small at night, when turtles rest, averaging 11% of the overall space use with the mean night‐time UD50 and UD95 being 0.15 km2 (SD = 0.1) and 1.1 km2 (SD = 0.8), respectively. Variation in home‐range across individuals was not influenced by the data volume (number of locations per day, duration of tracking) or animal size (carapace length) but increased significantly as the distance between the centre of day and night areas increased, that is individuals that had a larger daily commute had the larger home‐ranges.Synthesis and applications. Comparisons with home‐range estimates from 16 previous studies, showed that those we recorded are among the smallest for adult green turtles globally. These results suggest that despite population size increases at several major nesting sites in the Western Indian Ocean, green turtles are generally not destroying the seagrass meadows on which they forage and so management intervention to prevent overgrazing is not needed. In this way, our work illustrates how movement data may inform management decisions for green turtles. Further targeted work on the seagrass ecosystem health could help confirm this suggestion. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Using juvenile movements as a proxy for adult habitat and space use in long‐lived territorial species: a case study on the golden eagle
- Author
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Arzhela Hemery, Olivier Duriez, Christian Itty, Pierre‐Yves Henry, and Aurélien Besnard
- Subjects
Aquila chrysaetos ,GPS telemetry ,home-range ,land-cover ,topography ,Biology (General) ,QH301-705.5 ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Effective conservation management of wildlife species depends on understanding their space and habitat use. Telemetry has become the primary source of data for information on how species use space and habitats. However, animals can be difficult to capture, leading to limited sample sizes and thus low quality inferences. As some individuals may be easier to capture than others, it may be tempting to use them to make inferences about the studied population as a whole. Juvenile birds, in contrast to adults, are easy to capture while they are still in the nest. However, there are few studies on when and how they might serve to obtain a representative characterization of the habitat or space use of adults. This study investigated this by using GPS‐tracking data of 35 adult/juvenile dyads of golden eagles Aquila chrysaetos, with the juvenile and adult in a dyad sharing the same home‐range. We assessed juvenile‐to‐adult home‐range overlap and also compared their relative use of habitats within that space. We also analysed how these metrics evolved throughout the post‐fledging dependence period (PFDP). During this period, juvenile‐to‐adult similarity was more than 80% for the entire home‐range, whereas it was lower for the core area (approximately 60%). Habitat‐use similarity was high, at approximately 90% for both the home‐range and core area, both in land‐cover and topography. The similarity increased following the improvement of juvenile flight skills over a period of two months, to the extent that two months after fledging and until the end of the PFDP, habitat and space use of juveniles can be used to infer the home‐range and habitat requirements of adults. It would be valuable to study this ‘adult‐by‐juvenile replacement' approach in other species to determine whether it could be generalized, notably for species with a shorter dependence period or more complex social interactions.
- Published
- 2024
- Full Text
- View/download PDF
6. Land use drives differential resource selection by African elephants in the Greater Mara Ecosystem, Kenya
- Author
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Jake Wall, Nathan Hahn, Sarah Carroll, Stephen Mwiu, Marc Goss, Wilson Sairowua, Kate Tiedeman, Sospeter Kiambi, Patrick Omondi, Iain Douglas-Hamilton, and George Wittemyer
- Subjects
GPS tracking ,Home-range ,Resource selection ,Bayesian ,Loxodonta africana ,EarthRanger ,Biology (General) ,QH301-705.5 - Abstract
Abstract Understanding drivers of space use by African elephants is critical to their conservation and management, particularly given their large home-ranges, extensive resource requirements, ecological role as ecosystem engineers, involvement in human-elephant conflict and as a target species for ivory poaching. In this study we investigated resource selection by elephants inhabiting the Greater Mara Ecosystem in Southwestern Kenya in relation to three distinct but spatially contiguous management zones: (i) the government protected Maasai Mara National Reserve (ii) community-owned wildlife conservancies, and (iii) elephant range outside any formal wildlife protected area. We combined GPS tracking data from 49 elephants with spatial covariate information to compare elephant selection across these management zones using a hierarchical Bayesian framework, providing insight regarding how human activities structure elephant spatial behavior. We also contrasted differences in selection by zone across several data strata: sex, season and time-of-day. Our results showed that the strongest selection by elephants was for closed-canopy forest and the strongest avoidance was for open-cover, but that selection behavior varied significantly by management zone and selection for cover was accentuated in human-dominated areas. When contrasting selection parameters according to strata, variability in selection parameter values reduced along a protection gradient whereby elephants tended to behave more similarly (limited plasticity) in the human dominated, unprotected zone and more variably (greater plasticity) in the protected reserve. However, avoidance of slope was consistent across all zones. Differences in selection behavior was greatest between sexes, followed by time-of-day, then management zone and finally season (where seasonal selection showed the least differentiation of the contrasts assessed). By contrasting selection coefficients across strata, our analysis quantifies behavioural switching related to human presence and impact displayed by a cognitively advanced megaherbivore. Our study broadens the knowledge base about the movement ecology of African elephants and builds our capacity for both management and conservation.
- Published
- 2024
- Full Text
- View/download PDF
7. Land use drives differential resource selection by African elephants in the Greater Mara Ecosystem, Kenya.
- Author
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Wall, Jake, Hahn, Nathan, Carroll, Sarah, Mwiu, Stephen, Goss, Marc, Sairowua, Wilson, Tiedeman, Kate, Kiambi, Sospeter, Omondi, Patrick, Douglas-Hamilton, Iain, and Wittemyer, George
- Abstract
Understanding drivers of space use by African elephants is critical to their conservation and management, particularly given their large home-ranges, extensive resource requirements, ecological role as ecosystem engineers, involvement in human-elephant conflict and as a target species for ivory poaching. In this study we investigated resource selection by elephants inhabiting the Greater Mara Ecosystem in Southwestern Kenya in relation to three distinct but spatially contiguous management zones: (i) the government protected Maasai Mara National Reserve (ii) community-owned wildlife conservancies, and (iii) elephant range outside any formal wildlife protected area. We combined GPS tracking data from 49 elephants with spatial covariate information to compare elephant selection across these management zones using a hierarchical Bayesian framework, providing insight regarding how human activities structure elephant spatial behavior. We also contrasted differences in selection by zone across several data strata: sex, season and time-of-day. Our results showed that the strongest selection by elephants was for closed-canopy forest and the strongest avoidance was for open-cover, but that selection behavior varied significantly by management zone and selection for cover was accentuated in human-dominated areas. When contrasting selection parameters according to strata, variability in selection parameter values reduced along a protection gradient whereby elephants tended to behave more similarly (limited plasticity) in the human dominated, unprotected zone and more variably (greater plasticity) in the protected reserve. However, avoidance of slope was consistent across all zones. Differences in selection behavior was greatest between sexes, followed by time-of-day, then management zone and finally season (where seasonal selection showed the least differentiation of the contrasts assessed). By contrasting selection coefficients across strata, our analysis quantifies behavioural switching related to human presence and impact displayed by a cognitively advanced megaherbivore. Our study broadens the knowledge base about the movement ecology of African elephants and builds our capacity for both management and conservation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Changes in Flight Altitude of Black-Tailed Gulls According to Temporal and Environmental Differences.
- Author
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Park, Jong-Hyun, Jeong, In-Yong, Lee, Seung-Hae, Yoo, Jeong-Chil, and Lee, Who-Seung
- Subjects
- *
GULLS , *MATING grounds , *ALTITUDES , *FLEXIBLE display systems , *GPS receivers , *COLONIES (Biology) - Abstract
Simple Summary: Gulls are known for their adaptability and can navigate various environments from coastal and inland areas to marine spaces. Despite extensive studies using GPS tracking devices to explore the habitat use and flight patterns of numerous gull and other bird species, little such research has focused on the widely-distributed black-tailed gulls (Larus crassirostris) inhabiting the Korean Peninsula. To fill this gap in our understanding, our study employed GPS trackers to analyze the flight behavior and habitat use of black-tailed gulls. Our results unveiled distinct ranges of activity and flight altitudes that were influenced by both season and region. These findings suggest that the flight behavior of black-tailed gulls is responsive to environmental changes. Our study contributes fundamental data on the flight behavior of black-tailed gulls. In this study, GPS trackers were attached to black-tailed gulls (Larus crassirostris) breeding on five islands in Republic of Korea during April and May 2021, and their flight frequency, behavioral range, and flight altitude were compared during and after the breeding season. During the breeding season, the flight frequency was lowest on Dongman Island (28.7%), where mudflats were distributed nearby, and the range of activity was narrow. In contrast, it tended to be high on Gungsi Island (52%), where the breeding colony was far from land, resulting in a wider range of activity. Although the flight frequency on Dongman Island increased post-breeding season (42.7%), it decreased on other islands. The mean flight altitude during the breeding season was lowest on Dongman Island and highest on Napdaegi Island. In most breeding areas, the mean flight altitude during the post-breeding season was higher than that during the breeding season. However, the lead flight altitude was lower during the non-breeding season compared to that in the breeding season. The home range expanded after the breeding season, with no significant difference in lead time between the breeding and non-breeding seasons. Our findings reveal that black-tailed gulls exhibit varying home ranges and flight altitudes depending on season and geographical location. As generalists, gulls display flexible responses to environmental changes, indicating that flight behavior adapts to the evolving environment over time and across regions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Site‐specific space use and resource selection by Black Vultures (Coragyps atratus) in the southeastern USA.
- Author
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Evans, Betsy A., Humphrey, John S., Tillman, Eric A., Avery, Michael L., and Kluever, Bryan M.
- Subjects
EXTRATERRESTRIAL resources ,VULTURES ,FEATURE selection ,LANDSCAPE assessment ,NATURAL landscaping ,AMERICANS - Abstract
North American populations of Black Vultures Coragyps atratus have increased and expanded their distribution in the southern and eastern USA. In conjunction with these patterns has been a rise in human–vulture conflicts. To improve our understanding of space use patterns and better inform management, we evaluated the movements of Black Vultures (n = 23) in the southeastern USA using a long‐term GPS tracking database. Our specific objectives were to: (1) quantify home‐range sizes in relation to season and geographical study location and (2) examine within‐home‐range resource selection to identify landscape and anthropogenic factors influencing roost and diurnal space use. Home‐range sizes did not significantly differ between breeding and non‐breeding seasons. However, there were differences across geographical study locations, with the largest home‐ranges located in Florida. Similarly, there was limited seasonal variation in resource selection; however, use of anthropogenic features did vary by geographical study location. Overall Black Vultures avoided homogeneous landscapes regardless of season or activity and exhibited a strong selection for areas with increased landscape richness. Increased landscape richness, unlike homogeneous habitat, provides a diversity of resources for Black Vultures in a localized area, such as food, water, roosting and perch sites, and the creation of energy‐efficient flight opportunities. Contrasting with natural landscape feature selection, selection of anthropogenic features, such as landfill proximity and road density, was highly variable across individuals and study location. The high level of variation in selection for anthropogenic features provides further evidence of the propensity of Black Vultures to be flexible and opportunistic. The findings of this study stress the importance of using site‐specific studies effectively to understand and manage local vulture populations and mitigate associated human–vulture conflicts. Wildlife managers should exercise caution when implementing vulture management actions based on inferences from telemetry studies conducted in other geographical areas. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Space–time home‐range estimates and resource selection for the Critically Endangered Philippine Eagle on Mindanao.
- Author
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Sutton, Luke J., Ibañez, Jayson C., Salvador, Dennis I., Taraya, Rowell L., Opiso, Guiller S., Senarillos, Tristan Luap P., and McClure, Christopher J. W.
- Subjects
SPACETIME ,ANIMAL ecology ,ANIMAL mechanics ,HABITAT selection ,SECONDARY forests ,AGRICULTURE - Abstract
Quantifying home‐range size and habitat resource selection are important elements in wildlife ecology and are useful for informing conservation action. Many home‐range estimators and resource selection functions are currently in use. However, both methods are fraught with analytical issues inherent within autocorrelated movement data from irregular sampling and interpretation of resource selection model parameters to inform conservation management. Here, we apply satellite remote sensing technologies to provide updated estimates of home‐range size and first estimates of fine‐scale resource selection for six adult Philippine Eagles Pithecophaga jefferyi using a space–time autocorrelated kernel density estimate (AKDE) home‐range estimator and non‐parametric resource selection functions. All six adult Eagles showed distinct site fidelity, with continuous range residency between 2 and 18 km, 1 month after tagging. The space–time AKDE home‐range estimators had a median 95% home‐range size = 68 km2 (95% confidence interval (95% CI) 62–74 km2, range: 39–161 km2), with the median 50% core range size = 13 km2 (95% CI 11–14 km2, range 9–33 km2). From the resource selection functions, all adult Philippine Eagles used habitat high in photosynthetic leaf and canopy structure but avoided areas of old‐growth biomass and denser areas of vegetation. This is possibly due to foraging forays into secondary forest and fragmented agricultural areas away from nesting sites. For the first time, we determine two important fine‐scale spatial processes for this Critically Endangered raptor that can help in directing conservation management. Rather than employing traditional home‐range estimators and resource selection functions, we recommend that analysts consider space–time approaches and non‐parametric resource selection functions to animal movement data to explore fully space–time and resource selection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. Movement ecology of adult and juvenile spotted turtles (Clemmys guttata) in a seasonally dynamic environment.
- Author
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Lassiter, Ellery V., Sperry, Jinelle H., and DeGregorio, Brett A.
- Abstract
Context. Understanding the temporal and spatial scales at which wildlife move is vital for conservation and management. This is especially important for semi-aquatic species that make frequent inter-wetland movements to fulfil life-history requirements. Aims. We aimed to investigate the drivers of movement and space-use of the imperilled spotted turtle (Clemmys guttata), a seasonal wetland specialist, in three large, isolated wetland complexes in Virginia, USA. Methods. We used VHF radio-transmitters to radio-locate adult and juvenile turtles, and estimated movement and space-use during their active and aestivation seasons (March–August). We then used generalised linear mixed models to examine how movement and space-use varied, based on intrinsic turtle characteristics and extrinsic wetland and climatic factors. Key results. We show that, on average, individual spotted turtles used five wetlands per year (range 3–13), and that theirinter-wetland movement and movement distance varied seasonally in accordance with wetland availability and breeding phenology. Spotted turtle movement and space-use was influenced by the arrangement and size of the wetland complexes, with turtles moving further and occupying larger home-ranges as size and distance between wetlands increased. Inter-wetland movement was not influenced by intrinsic turtle effects but larger adult turtles moved further, used more wetlands, and had larger home-ranges than smaller turtles. Conclusions. Turtle responses to variation in season and wetland configuration highlight the need for complex and dynamic landscapes required to sustain this species. Implications. This study has important conservation implications showing that spotted turtlesrely on a large number of diverse wetlands, as well as upland habitat, to fulfil their resource needs – and that these habitat associations vary seasonally. Results from our study can aid the understanding of spatial and temporal variation in patch characteristics (e.g. quality and extent) and inter-patch movement by organisms, which is critical for the conservation and management of semi-aquatic species and other organisms that occupy patchy habitat complexes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
12. First results from the releases of Cinereous Vultures (Aegypius monachus) aiming at re-introducing the species in Bulgaria – the start of the establishment phase 2018–2022
- Author
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Ivanov, Ivelin, Stoynov, Emilian, Stoyanov, Georgi, Kmetova–biro, Elena, Andevski, Jovan, Peshev, Hristo, Marin, Simeon, Terraube, Julien, Bonchev, Lachezar, Stoev, Iliyan, Tavares, Jose, Loercher, Franziska, Huyghe, Marleen, Nikolova, Zlatka, Vangelova, Nadya, Stanchev, Stamen, Mitrevichin, Emanuil, Tilova, Elena, Grozdanov, Atanas, and Pensoft Publishers
- Subjects
artificial nest platforms ,Balkan Mountains ,evaluation in conservation management ,home-range ,Kotlenska planina SPA ,raptor ,re-introduction strategy ,release by hacking (artificial nest) ,release from aviary ,Sinite Kamani Nature Park ,Survival rate ,Vrachanski Balkan Nature Park - Published
- 2023
13. Which bird traits most affect the goodness-of-fit of species distribution models?
- Author
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Federico Morelli, Yanina Benedetti, Jesse Stanford, Leszek Jerzak, Piotr Tryjanowski, Paolo Perna, and Riccardo Santolini
- Subjects
AUC ,Ecological traits ,Farmland birds ,Forest birds ,Home-range ,SDMs ,Ecology ,QH540-549.5 - Abstract
Species distribution models (SDMs) are numerical tools that combine species occurrence (or abundance) data with environmental variables, to predict the species’ distribution spatially. SDMs are increasingly used for purposes of conservation planning and management of ecosystems. The model performance can be measured as the goodness-of-fit (GOF), which describes how well it fits (e.g., the discrepancy between the statistical model and the data observed). However, there is still a need for a deeper understanding of the ecological characteristics of the modelled species which can affect the accuracy of those models. Here, we compared the goodness-of-fit of SDMs, considering several ecological characteristics of 56 bird species: Most frequently used environment, body mass, home-range, species specialization index (SSI), diet specialization and detectability. All SDMs were performed on the same dataset, and the relative frequency of each species was also incorporated to account for occurrence heterogeneity. GOF of SDMs was not significantly correlated with species’ frequency, home-range, body mass, degree of detectability or level of diet specialization. Overall, the birds with more accurate SDMs (GOF) were species of grasslands and the GOF was positively associated with SSI, indicating that more habitat-specialized species are better predictable. Our findings suggest that is important to focus not only on statistical issues potentially related to model performance but also on ecological characteristics of single species because can improve the performance of modellistic procedures, increasing their predictive power.
- Published
- 2024
- Full Text
- View/download PDF
14. Ferruginous Hawk movements respond predictably to intra‐annual variation but unexpectedly to anthropogenic habitats.
- Author
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Isted, Georgia H., Thomas, Robert J., Warner, Kevin S., Stuber, Matthew J., Ellsworth, Ethan, and Katzner, Todd E.
- Subjects
ANIMAL sexual behavior ,HAWKS ,HABITATS ,PROHEXADIONE-calcium ,LAND cover ,PREDATION ,PREY availability - Abstract
Birds exhibit flexible movement responses to environmental variation across the annual cycle, and those responses can provide insight into potential impacts that environmental changes may have on these species. To understand year‐round variation in space use by Ferruginous Hawks Buteo regalis, we tracked 12 birds breeding in southwestern Idaho, USA, using GPS telemetry collected over 207 bird‐months. Home‐range sizes of territorial adult hawks showed strong intra‐annual variation, being smallest from April to June and largest from July to October. In contrast, juvenile birds (< 2 years old) did not appear to hold territories and showed no detectable intra‐annual variation in ranging behaviour. Association with land‐cover types by territorial birds varied between breeding and non‐breeding months and was linked to home‐range size. Home‐range sizes of non‐territorial birds were larger than those of territorial birds, and that size did not vary across the year. Association with anthropogenic habitats (irrigated cropland habitats that can provide high rodent densities and increased foraging opportunities) was negatively associated with home‐range size in months of the non‐breeding season. Unexpectedly, the opposite was true in the months of the breeding season, such that use of croplands resulted in larger home‐ranges. Patterns in home‐range size were probably linked to intrinsic factors such as the timing of breeding and migratory behaviour, and to extrinsic factors such as prey availability associated with specific land‐cover types. These results have implications for our understanding of the response of Ferruginous Hawks and other similar species to predicted changes in land cover, and they suggest unexpected relationships between human activity and wildlife behaviour. Furthermore, because the birds we tracked used a large portion of western North America, they are probably relevant far beyond the small area where these individuals were trapped. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
15. Changes in Flight Altitude of Black-Tailed Gulls According to Temporal and Environmental Differences
- Author
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Jong-Hyun Park, In-Yong Jeong, Seung-Hae Lee, Jeong-Chil Yoo, and Who-Seung Lee
- Subjects
black-tailed gull ,flight height ,home-range ,GPS tracking ,Veterinary medicine ,SF600-1100 ,Zoology ,QL1-991 - Abstract
In this study, GPS trackers were attached to black-tailed gulls (Larus crassirostris) breeding on five islands in Republic of Korea during April and May 2021, and their flight frequency, behavioral range, and flight altitude were compared during and after the breeding season. During the breeding season, the flight frequency was lowest on Dongman Island (28.7%), where mudflats were distributed nearby, and the range of activity was narrow. In contrast, it tended to be high on Gungsi Island (52%), where the breeding colony was far from land, resulting in a wider range of activity. Although the flight frequency on Dongman Island increased post-breeding season (42.7%), it decreased on other islands. The mean flight altitude during the breeding season was lowest on Dongman Island and highest on Napdaegi Island. In most breeding areas, the mean flight altitude during the post-breeding season was higher than that during the breeding season. However, the lead flight altitude was lower during the non-breeding season compared to that in the breeding season. The home range expanded after the breeding season, with no significant difference in lead time between the breeding and non-breeding seasons. Our findings reveal that black-tailed gulls exhibit varying home ranges and flight altitudes depending on season and geographical location. As generalists, gulls display flexible responses to environmental changes, indicating that flight behavior adapts to the evolving environment over time and across regions.
- Published
- 2024
- Full Text
- View/download PDF
16. Large‐scale movement patterns in a social vulture are influenced by seasonality, sex, and breeding region.
- Author
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Morant, Jon, Arrondo, Eneko, Sánchez‐Zapata, José Antonio, Donázar, José Antonio, Cortés‐Avizanda, Ainara, De La Riva, Manuel, Blanco, Guillermo, Martínez, Félix, Oltra, Juan, Carrete, Martina, Margalida, Antoni, Oliva‐Vidal, Pilar, Martínez, José Maria, Serrano, David, and Pérez‐García, Juan Manuel
- Subjects
- *
SOCIAL movements , *VULTURES , *SPRING , *REPRODUCTION - Abstract
Quantifying space use and segregation, as well as the extrinsic and intrinsic factors affecting them, is crucial to increase our knowledge of species‐specific movement ecology and to design effective management and conservation measures. This is particularly relevant in the case of species that are highly mobile and dependent on sparse and unpredictable trophic resources, such as vultures. Here, we used the GPS‐tagged data of 127 adult Griffon Vultures Gyps fulvus captured at five different breeding regions in Spain to describe the movement patterns (home‐range size and fidelity, and monthly cumulative distance). We also examined how individual sex, season, and breeding region determined the cumulative distance traveled and the size and overlap between consecutive monthly home‐ranges. Overall, Griffon Vultures exhibited very large annual home‐range sizes of 5027 ± 2123 km2, mean monthly cumulative distances of 1776 ± 1497 km, and showed a monthly home‐range fidelity of 67.8 ± 25.5%. However, individuals from northern breeding regions showed smaller home‐ranges and traveled shorter monthly distances than those from southern ones. In all cases, home‐ranges were larger in spring and summer than in winter and autumn, which could be related to difference in flying conditions and food requirements associated with reproduction. Moreover, females showed larger home‐ranges and less monthly fidelity than males, indicating that the latter tended to use the similar areas throughout the year. Overall, our results indicate that both extrinsic and intrinsic factors modulate the home‐range of the Griffon Vulture and that spatial segregation depends on sex and season at the individual level, without relevant differences between breeding regions in individual site fidelity. These results have important implications for conservation, such as identifying key threat factors necessary to improve management actions and policy decisions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
17. Detectability of ten invasive mammal pests in New Zealand: a synthesis of spatial detection parameters.
- Author
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Vattiato, Giorgia, Binny, Rachelle N., Davidson, Sam J., Byrom, Andrea E., Anderson, Dean P., Plank, Michael J., Carpenter, Joanna K., and James, Alex
- Abstract
Management of invasive mammal pests plays an integral role in the conservation of New Zealand's native flora and fauna. Models fitted to pest capture data can guide conservation managers by providing estimates of pest densities within a management area, or probabilities of absence for declaring local eradication. A key parameter of these models is the detectability, i.e. the probability of an animal being detected by a surveillance device for a given amount of survey effort. In this paper, we conduct a comprehensive review of both spatially explicit capture-recapture and home-range studies reporting estimates of two commonly applied spatial detectability parameters for ten of New Zealand's invasive mammal pests. We summarise study attributes including habitat, season, and surveillance device type, to assess how detectability varies over different environmental, biological, and survey conditions, and to identify knowledge gaps for prioritising future research. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. GPS-tracking reveals annual variation in home-range and sedentary behaviour in Common Kestrels breeding in central Italy.
- Author
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DAMIANI, GIANLUCA, JENNINGS, VALERIA, DELL'OMO, GIACOMO, and COSTANTINI, DAVID
- Subjects
- *
GLOBAL Positioning System , *SEDENTARY behavior , *KESTRELS , *BIRD breeding , *SPECIES diversity , *SPECIES distribution - Abstract
We studied the movements of Common Kestrels Falco tinnunculus in central Italy by GPS-tracking 10 individuals between 2019 and 2021. Our aim was to investigate the extent of movements during the breeding and non-breeding seasons. In the breeding season the mean home-range size increased from incubation (1.11 km2) to the chick-rearing period (3.35 km2), and the average home-range for the entire study period was 3.68 km2. In winter, all tagged individuals remained within a few hundred meters of their nesting area, revealing for the first time a non-migratory behaviour for the species. In conclusion, our study provides novel data on the movement ecology of Kestrels during both the breeding and non-breeding seasons, and documented the resident behaviour of Kestrels in central Italy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
19. Animal movement ecology in India: insights from 2011-2021 and prospective for the future.
- Author
-
Prakash, Harish, Kumar, R. Suresh, Lahkar, Bibhuti, Sukumar, Raman, Vanak, Abi T., and Thaker, Maria
- Subjects
ANIMAL ecology ,ANIMAL mechanics ,ANIMAL tracks ,HABITATS ,DATABASES ,AQUATIC animals - Abstract
The field of animal movement ecology has advanced by leaps and bounds in the past few decades with the advent of sophisticated technology, advanced analytical tools, and multiple frameworks and paradigms to address key ecological problems. Unlike the longer history and faster growth of the field in North America, Europe, and Africa, movement ecology in Asia has only recently been gaining momentum. Here, we provide a review of the field from studies based in India over the last 11 years (2011-2021) curated from the database, Scopus, and search engine, Google Scholar. We identify current directions in the research objectives, taxa studied, tracking technology and the biogeographic regions in which animals were tracked, considering the years since the last systematic review of movement ecology research in the country. As an indication of the growing interest in this field, there has been a rapid increase in the number of publications over the last decade. Class Mammalia continues to dominate the taxa tracked, with tiger and leopard being the most common species studied across publications. Invertebrates and other small and medium-sized animals, as well as aquatic animals, in comparison, are understudied and remain among the important target taxa for tracking in future studies. As in the previous three decades, researchers have focussed on characterising home ranges and habitat use of animals. There is, however, a notable shift to examine the movement decision of animals in human-modified landscapes, although efforts to use movement ecology to understand impacts of climate change remain missing. Given the biogeographic and taxonomic diversity of India, and the fact that the interface between anthropogenic activity and wildlife interactions is increasing, we suggest ways in which the field of movement ecology can be expanded to facilitate ecological insights and conservation efforts. With the advancement of affordable technologies and the availability of analytical tools, the potential to expand the field of movement ecology, shift research foci, and gain new insights is now prime. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Dead-reckoning elucidates fine-scale habitat use by European badgers Meles meles
- Author
-
E. A. Magowan, I. E. Maguire, S. Smith, S. Redpath, N. J. Marks, R. P. Wilson, F. Menzies, M. O’Hagan, and D. M. Scantlebury
- Subjects
Dead-reckoning ,Badger ,Home-range ,Distance travelled ,Movement ,Accelerometer ,Ecology ,QH540-549.5 ,Animal biochemistry ,QP501-801 - Abstract
Abstract Background Recent developments in both hardware and software of animal-borne data loggers now enable large amounts of data to be collected on both animal movement and behaviour. In particular, the combined use of tri-axial accelerometers, tri-axial magnetometers and GPS loggers enables animal tracks to be elucidated using a procedure of ‘dead-reckoning’. Although this approach was first suggested 30 years ago by Wilson et al. (1991), surprisingly few measurements have been made in free-ranging terrestrial animals. The current study examines movements, interactions with habitat features, and home-ranges calculated from just GPS data and also from dead-reckoned data in a model terrestrial mammal, the European badger (Meles meles). Methods Research was undertaken in farmland in Northern Ireland. Two badgers (one male, one female) were live-trapped and fitted with a GPS logger, a tri-axial accelerometer, and a tri-axial magnetometer. Thereafter, the badgers’ movement paths over 2 weeks were elucidated using just GPS data and GPS-enabled dead-reckoned data, respectively. Results Badgers travelled further using data from dead-reckoned calculations than using the data from only GPS data. Whilst once-hourly GPS data could only be represented by straight-line movements between sequential points, the sub-second resolution dead-reckoned tracks were more tortuous. Although there were no differences in Minimum Convex Polygon determinations between GPS- and dead-reckoned data, Kernel Utilisation Distribution determinations of home-range size were larger using the former method. This was because dead-reckoned data more accurately described the particular parts of landscape constituting most-visited core areas, effectively narrowing the calculation of habitat use. Finally, the dead-reckoned data showed badgers spent more time near to field margins and hedges than simple GPS data would suggest. Conclusion Significant differences emerge when analyses of habitat use and movements are compared between calculations made using just GPS data or GPS-enabled dead-reckoned data. In particular, use of dead-reckoned data showed that animals moved 2.2 times farther, had better-defined use of the habitat (revealing clear core areas), and made more use of certain habitats (field margins, hedges). Use of dead-reckoning to provide detailed accounts of animal movement and highlight the minutiae of interactions with the environment should be considered an important technique in the ecologist’s toolkit.
- Published
- 2022
- Full Text
- View/download PDF
21. Large‐scale movement patterns in a social vulture are influenced by seasonality, sex, and breeding region
- Author
-
Jon Morant, Eneko Arrondo, José Antonio Sánchez‐Zapata, José Antonio Donázar, Ainara Cortés‐Avizanda, Manuel De La Riva, Guillermo Blanco, Félix Martínez, Juan Oltra, Martina Carrete, Antoni Margalida, Pilar Oliva‐Vidal, José Maria Martínez, David Serrano, and Juan Manuel Pérez‐García
- Subjects
griffon vulture ,home‐range ,scavenger ,site fidelity ,spatial segregation ,Ecology ,QH540-549.5 - Abstract
Abstract Quantifying space use and segregation, as well as the extrinsic and intrinsic factors affecting them, is crucial to increase our knowledge of species‐specific movement ecology and to design effective management and conservation measures. This is particularly relevant in the case of species that are highly mobile and dependent on sparse and unpredictable trophic resources, such as vultures. Here, we used the GPS‐tagged data of 127 adult Griffon Vultures Gyps fulvus captured at five different breeding regions in Spain to describe the movement patterns (home‐range size and fidelity, and monthly cumulative distance). We also examined how individual sex, season, and breeding region determined the cumulative distance traveled and the size and overlap between consecutive monthly home‐ranges. Overall, Griffon Vultures exhibited very large annual home‐range sizes of 5027 ± 2123 km2, mean monthly cumulative distances of 1776 ± 1497 km, and showed a monthly home‐range fidelity of 67.8 ± 25.5%. However, individuals from northern breeding regions showed smaller home‐ranges and traveled shorter monthly distances than those from southern ones. In all cases, home‐ranges were larger in spring and summer than in winter and autumn, which could be related to difference in flying conditions and food requirements associated with reproduction. Moreover, females showed larger home‐ranges and less monthly fidelity than males, indicating that the latter tended to use the similar areas throughout the year. Overall, our results indicate that both extrinsic and intrinsic factors modulate the home‐range of the Griffon Vulture and that spatial segregation depends on sex and season at the individual level, without relevant differences between breeding regions in individual site fidelity. These results have important implications for conservation, such as identifying key threat factors necessary to improve management actions and policy decisions.
- Published
- 2023
- Full Text
- View/download PDF
22. Animal movement ecology in India: insights from 2011–2021 and prospective for the future
- Author
-
Harish Prakash, R. Suresh Kumar, Bibhuti Lahkar, Raman Sukumar, Abi T. Vanak, and Maria Thaker
- Subjects
Movement ecology ,Tracking ,Telemetry ,Home-range ,Protected areas ,Anthropogenic ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
The field of animal movement ecology has advanced by leaps and bounds in the past few decades with the advent of sophisticated technology, advanced analytical tools, and multiple frameworks and paradigms to address key ecological problems. Unlike the longer history and faster growth of the field in North America, Europe, and Africa, movement ecology in Asia has only recently been gaining momentum. Here, we provide a review of the field from studies based in India over the last 11 years (2011–2021) curated from the database, Scopus, and search engine, Google Scholar. We identify current directions in the research objectives, taxa studied, tracking technology and the biogeographic regions in which animals were tracked, considering the years since the last systematic review of movement ecology research in the country. As an indication of the growing interest in this field, there has been a rapid increase in the number of publications over the last decade. Class Mammalia continues to dominate the taxa tracked, with tiger and leopard being the most common species studied across publications. Invertebrates and other small and medium-sized animals, as well as aquatic animals, in comparison, are understudied and remain among the important target taxa for tracking in future studies. As in the previous three decades, researchers have focussed on characterising home ranges and habitat use of animals. There is, however, a notable shift to examine the movement decision of animals in human-modified landscapes, although efforts to use movement ecology to understand impacts of climate change remain missing. Given the biogeographic and taxonomic diversity of India, and the fact that the interface between anthropogenic activity and wildlife interactions is increasing, we suggest ways in which the field of movement ecology can be expanded to facilitate ecological insights and conservation efforts. With the advancement of affordable technologies and the availability of analytical tools, the potential to expand the field of movement ecology, shift research foci, and gain new insights is now prime.
- Published
- 2022
- Full Text
- View/download PDF
23. Weak niche partitioning between closely related sympatric Greater (Clanga clanga) and Lesser Spotted Eagles (C. pomarina).
- Author
-
Väli, Ülo, Abel, Urmas, Nellis, Renno, Sein, Gunnar, Sellis, Urmas, and Mirski, Paweł
- Subjects
HABITATS ,TOP predators ,COEXISTENCE of species ,ECOLOGICAL niche ,COMPETITION (Biology) ,VOLES ,LAND use - Abstract
Species coexist only when occupying different ecological niches. We evaluated habitat and trophic niches in two recently diverged hybridizing avian apex predators, the declining Greater Spotted Eagle Clanga clanga (mainly found in contracting wetlands) and the more numerous Lesser Spotted Eagle Clanga pomarina (inhabiting mosaic farmlands). We tracked 24 Spotted Eagles, including interspecific hybrids, by GPS to estimate the home‐range size, land use composition and landscape structure in sympatric populations. In addition to information for landscape utilization, data for diet composition were evaluated. Home‐ranges of the two species were similar in size and open foraging habitats consisted mostly of agricultural landscape. However, landscape utilization of the Greater Spotted Eagle was largely driven by the composition of land‐use types, whereas the Lesser Spotted Eagle was mostly influenced by structural components of the landscape. Farmland‐dwelling voles accounted for the bulk of the diet in both species; however, subdominant prey classes differed. Hybrids exhibited intermediate or mixed features of home‐ranges and diets. Our results provide evidence for reduced niche partitioning and potential competition between the two Spotted Eagles, which may have been reinforced by anthropogenic habitat alteration. A closer examination of movement patterns revealed previously overlooked differences between closely related species with respect to landscape utilization strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
24. Assessing the use of marine protected areas by loggerhead sea turtles (Caretta caretta) tracked from the western Mediterranean
- Author
-
Sara Abalo-Morla, Eduardo J. Belda, David March, Ohiana Revuelta, Luis Cardona, Silvia Giralt, Jose Luis Crespo-Picazo, Sandra Hochscheid, Adolfo Marco, Manuel Merchán, Ricardo Sagarminaga, Yonat Swimmer, and Jesús Tomás
- Subjects
Caretta caretta ,Marine Protected Area ,Home-range ,Kernel utilization distribution ,Satellite tracking ,Mediterranean Sea ,Ecology ,QH540-549.5 - Abstract
Up to date 264 Marine Protected Areas (MPAs) have been declared in the western Mediterranean Sea. The management plans of 25 of these MPAs include the loggerhead sea turtle (Caretta caretta) as a priority species to protect. However, the actual use of these MPAs by the species remains unknown. Therefore, it is important to assess their contribution to loggerhead conservation in the area. To this end, satellite tracking data of 103 loggerhead turtles of varying sizes and life stages released in Spanish Mediterranean waters and Southern Tyrrhenian Sea over the 2003–2018 period were herein used. Home range and use of MPAs by tracked loggerhead turtles were analysed using post-processed state-space model locations. The tracked turtles visited several Mediterranean MPAs, but barely used them (mean percentage of monitoring time=12.6 ± 18.2 %). There was very little overlap between turtle’s core areas and tracks with the protected areas. Indeed, most of the core areas and high-density areas estimated (>85 %) were not included within any of the MPAs. Furthermore, less than 5 % of the Mediterranean MPAs were used by any tracked loggerhead sea turtles. Most of these MPAs have no protection measures that focus on this species. Loggerheads mainly use wide oceanic zones and international waters, which are difficult to protect. A high-use core area was identified for loggerhead turtles, located at the western waters of the Algerian Basin, an important fishing area outside any designated MPA and with no protection measures that focus on marine turtle conservation. We conclude that existing MPAs in the western Mediterranean may not contribute enough to loggerhead turtle conservation. We propose potential MPAs designations to be considered for loggerhead sea turtle conservation in the Mediterranean Sea at the Alboran Sea, the Algerian basin, the Northern area of the Strait of Sicily, Northeast Tunisian waters, waters around Malta, waters at the Tyrrhenian Sea and at the Ionian Sea.
- Published
- 2022
- Full Text
- View/download PDF
25. Seasonality impacts collective movements in a wild group-living bird
- Author
-
Danai Papageorgiou, David Rozen-Rechels, Brendah Nyaguthii, and Damien R. Farine
- Subjects
Avian ecology ,Climate change ,Collective movement ,Drought ,Home-range ,Movement ecology ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background A challenge faced by animals living in groups with stable long-term membership is to effectively coordinate their actions and maintain cohesion. However, as seasonal conditions alter the distribution of resources across a landscape, they can change the priority of group members and require groups to adapt and respond collectively across changing contexts. Little is known about how stable group-living animals collectively modify their movement behaviour in response to environment changes, such as those induced by seasonality. Further, it remains unclear how environment-induced changes in group-level movement behaviours might scale up to affect population-level properties, such as a population’s footprint. Methods Here we studied the collective movement of each distinct social group in a population of vulturine guineafowl (Acryllium vulturinum), a largely terrestrial and non-territorial bird. We used high-resolution GPS tracking of group members over 22 months, combined with continuous time movement models, to capture how and where groups moved under varying conditions, driven by seasonality and drought. Results Groups used larger areas, travelled longer distances, and moved to new places more often during drier seasons, causing a three-fold increase in the area used at the population level when conditions turned to drought. By contrast, groups used smaller areas with more regular movements during wetter seasons. Conclusions The consistent changes in collective outcomes we observed in response to different environments raise questions about the role of collective behaviour in facilitating, or impeding, the capacity for individuals to respond to novel environmental conditions. As droughts will be occurring more often under climate change, some group living animals may have to respond to them by expressing dramatic shifts in their regular movement patterns. These shifts can have consequences on their ranging behaviours that can scale up to alter the footprints of animal populations.
- Published
- 2021
- Full Text
- View/download PDF
26. Caution is warranted when using animal space-use and movement to infer behavioral states
- Author
-
Frances E. Buderman, Tess M. Gingery, Duane R. Diefenbach, Laura C. Gigliotti, Danielle Begley-Miller, Marc M. McDill, Bret D. Wallingford, Christopher S. Rosenberry, and Patrick J. Drohan
- Subjects
Breeding ,Mate search strategy ,Odocoileus virginianus ,White-tailed deer ,Hidden Markov models ,Home-range ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Identifying the behavioral state for wild animals that can’t be directly observed is of growing interest to the ecological community. Advances in telemetry technology and statistical methodologies allow researchers to use space-use and movement metrics to infer the underlying, latent, behavioral state of an animal without direct observations. For example, researchers studying ungulate ecology have started using these methods to quantify behaviors related to mating strategies. However, little work has been done to determine if assumed behaviors inferred from movement and space-use patterns correspond to actual behaviors of individuals. Methods Using a dataset with male and female white-tailed deer location data, we evaluated the ability of these two methods to correctly identify male-female interaction events (MFIEs). We identified MFIEs using the proximity of their locations in space as indicators of when mating could have occurred. We then tested the ability of utilization distributions (UDs) and hidden Markov models (HMMs) rendered with single sex location data to identify these events. Results For white-tailed deer, male and female space-use and movement behavior did not vary consistently when with a potential mate. There was no evidence that a probability contour threshold based on UD volume applied to an individual’s UD could be used to identify MFIEs. Additionally, HMMs were unable to identify MFIEs, as single MFIEs were often split across multiple states and the primary state of each MFIE was not consistent across events. Conclusions Caution is warranted when interpreting behavioral insights rendered from statistical models applied to location data, particularly when there is no form of validation data. For these models to detect latent behaviors, the individual needs to exhibit a consistently different type of space-use and movement when engaged in the behavior. Unvalidated assumptions about that relationship may lead to incorrect inference about mating strategies or other behaviors.
- Published
- 2021
- Full Text
- View/download PDF
27. Dead-reckoning elucidates fine-scale habitat use by European badgers Meles meles.
- Author
-
Magowan, E. A., Maguire, I. E., Smith, S., Redpath, S., Marks, N. J., Wilson, R. P., Menzies, F., O'Hagan, M., and Scantlebury, D. M.
- Subjects
- *
OLD World badger , *ANIMAL tracks , *ANIMAL behavior , *ANIMAL mechanics , *HABITATS , *BADGERS , *DEAD - Abstract
Background: Recent developments in both hardware and software of animal-borne data loggers now enable large amounts of data to be collected on both animal movement and behaviour. In particular, the combined use of tri-axial accelerometers, tri-axial magnetometers and GPS loggers enables animal tracks to be elucidated using a procedure of 'dead-reckoning'. Although this approach was first suggested 30 years ago by Wilson et al. (1991), surprisingly few measurements have been made in free-ranging terrestrial animals. The current study examines movements, interactions with habitat features, and home-ranges calculated from just GPS data and also from dead-reckoned data in a model terrestrial mammal, the European badger (Meles meles). Methods: Research was undertaken in farmland in Northern Ireland. Two badgers (one male, one female) were live-trapped and fitted with a GPS logger, a tri-axial accelerometer, and a tri-axial magnetometer. Thereafter, the badgers' movement paths over 2 weeks were elucidated using just GPS data and GPS-enabled dead-reckoned data, respectively. Results: Badgers travelled further using data from dead-reckoned calculations than using the data from only GPS data. Whilst once-hourly GPS data could only be represented by straight-line movements between sequential points, the sub-second resolution dead-reckoned tracks were more tortuous. Although there were no differences in Minimum Convex Polygon determinations between GPS- and dead-reckoned data, Kernel Utilisation Distribution determinations of home-range size were larger using the former method. This was because dead-reckoned data more accurately described the particular parts of landscape constituting most-visited core areas, effectively narrowing the calculation of habitat use. Finally, the dead-reckoned data showed badgers spent more time near to field margins and hedges than simple GPS data would suggest. Conclusion: Significant differences emerge when analyses of habitat use and movements are compared between calculations made using just GPS data or GPS-enabled dead-reckoned data. In particular, use of dead-reckoned data showed that animals moved 2.2 times farther, had better-defined use of the habitat (revealing clear core areas), and made more use of certain habitats (field margins, hedges). Use of dead-reckoning to provide detailed accounts of animal movement and highlight the minutiae of interactions with the environment should be considered an important technique in the ecologist's toolkit. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
28. Unsustainable anthropogenic mortality disrupts natal dispersal and promotes inbreeding in leopards
- Author
-
Vincent N. Naude, Guy A. Balme, Justin O'Riain, Luke T.B. Hunter, Julien Fattebert, Tristan Dickerson, and Jacqueline M. Bishop
- Subjects
home‐range ,kin‐clustering ,microsatellites ,Panthera pardus ,philopatry ,relatedness ,Ecology ,QH540-549.5 - Abstract
Abstract Anthropogenic mortality of wildlife is typically inferred from measures of the absolute decline in population numbers. However, increasing evidence suggests that indirect demographic effects including changes to the age, sex, and social structure of populations, as well as the behavior of survivors, can profoundly impact population health and viability. Specifically, anthropogenic mortality of wildlife (especially when unsustainable) and fragmentation of the spatial distribution of individuals (home‐ranges) could disrupt natal dispersal mechanisms, with long‐term consequences to genetic structure, by compromising outbreeding behavior and gene flow. We investigate this threat in African leopards (Panthera pardus pardus), a polygynous felid with male‐biased natal dispersal. Using a combination of spatial (home‐range) and genetic (21 polymorphic microsatellites) data from 142 adult leopards, we contrast the structure of two South African populations with markedly different histories of anthropogenically linked mortality. Home‐range overlap, parentage assignment, and spatio‐genetic autocorrelation together show that historical exploitation of leopards in a recovering protected area has disrupted and reduced subadult male dispersal, thereby facilitating opportunistic male natal philopatry, with sons establishing territories closer to their mothers and sisters. The resultant kin‐clustering in males of this historically exploited population is comparable to that of females in a well‐protected reserve and has ultimately led to localized inbreeding. Our findings demonstrate novel evidence directly linking unsustainable anthropogenic mortality to inbreeding through disrupted dispersal in a large, solitary felid and expose the genetic consequences underlying this behavioral change. We therefore emphasize the importance of managing and mitigating the effects of unsustainable exploitation on local populations and increasing habitat fragmentation between contiguous protected areas by promoting in situ recovery and providing corridors of suitable habitat that maintain genetic connectivity.
- Published
- 2020
- Full Text
- View/download PDF
29. Seasonality impacts collective movements in a wild group-living bird.
- Author
-
Papageorgiou, Danai, Rozen-Rechels, David, Nyaguthii, Brendah, and Farine, Damien R.
- Subjects
ANIMAL mechanics ,ACRYLLIUM vulturinum ,CLIMATE change ,BIRD ecology ,HOME range (Animal geography) - Abstract
Background: A challenge faced by animals living in groups with stable long-term membership is to effectively coordinate their actions and maintain cohesion. However, as seasonal conditions alter the distribution of resources across a landscape, they can change the priority of group members and require groups to adapt and respond collectively across changing contexts. Little is known about how stable group-living animals collectively modify their movement behaviour in response to environment changes, such as those induced by seasonality. Further, it remains unclear how environment-induced changes in group-level movement behaviours might scale up to affect population-level properties, such as a population's footprint. Methods: Here we studied the collective movement of each distinct social group in a population of vulturine guineafowl (Acryllium vulturinum), a largely terrestrial and non-territorial bird. We used high-resolution GPS tracking of group members over 22 months, combined with continuous time movement models, to capture how and where groups moved under varying conditions, driven by seasonality and drought. Results: Groups used larger areas, travelled longer distances, and moved to new places more often during drier seasons, causing a three-fold increase in the area used at the population level when conditions turned to drought. By contrast, groups used smaller areas with more regular movements during wetter seasons. Conclusions: The consistent changes in collective outcomes we observed in response to different environments raise questions about the role of collective behaviour in facilitating, or impeding, the capacity for individuals to respond to novel environmental conditions. As droughts will be occurring more often under climate change, some group living animals may have to respond to them by expressing dramatic shifts in their regular movement patterns. These shifts can have consequences on their ranging behaviours that can scale up to alter the footprints of animal populations. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
30. Caution is warranted when using animal space-use and movement to infer behavioral states.
- Author
-
Buderman, Frances E., Gingery, Tess M., Diefenbach, Duane R., Gigliotti, Laura C., Begley-Miller, Danielle, McDill, Marc M., Wallingford, Bret D., Rosenberry, Christopher S., and Drohan, Patrick J.
- Subjects
ANIMALS ,BIOTIC communities ,WHITE-tailed deer ,HIDDEN Markov models ,ANIMAL courtship - Abstract
Background: Identifying the behavioral state for wild animals that can't be directly observed is of growing interest to the ecological community. Advances in telemetry technology and statistical methodologies allow researchers to use space-use and movement metrics to infer the underlying, latent, behavioral state of an animal without direct observations. For example, researchers studying ungulate ecology have started using these methods to quantify behaviors related to mating strategies. However, little work has been done to determine if assumed behaviors inferred from movement and space-use patterns correspond to actual behaviors of individuals. Methods: Using a dataset with male and female white-tailed deer location data, we evaluated the ability of these two methods to correctly identify male-female interaction events (MFIEs). We identified MFIEs using the proximity of their locations in space as indicators of when mating could have occurred. We then tested the ability of utilization distributions (UDs) and hidden Markov models (HMMs) rendered with single sex location data to identify these events. Results: For white-tailed deer, male and female space-use and movement behavior did not vary consistently when with a potential mate. There was no evidence that a probability contour threshold based on UD volume applied to an individual's UD could be used to identify MFIEs. Additionally, HMMs were unable to identify MFIEs, as single MFIEs were often split across multiple states and the primary state of each MFIE was not consistent across events. Conclusions: Caution is warranted when interpreting behavioral insights rendered from statistical models applied to location data, particularly when there is no form of validation data. For these models to detect latent behaviors, the individual needs to exhibit a consistently different type of space-use and movement when engaged in the behavior. Unvalidated assumptions about that relationship may lead to incorrect inference about mating strategies or other behaviors. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
31. Space use and movement patterns of translocated bighorn sheep.
- Author
-
Werdel, Ty J., Jenks, Jonathan A., Kanta, John T., Lehman, Chadwick P., and Frink, Teresa J.
- Subjects
- *
BIGHORN sheep , *BROWNIAN motion , *UNGULATES , *ANIMAL herds , *ACCLIMATIZATION , *POLYGONS - Abstract
Ungulate species have consistently been a major focus of reintroductions to their native ranges. Bighorn sheep (Ovis canadensis) are an ecologically sensitive species, and have experienced population declines throughout their historic range; bighorn sheep inhabited the Black Hills region of South Dakota but were extirpated from the area due to anthropogenic impacts in the early 1900s. To continue to restore populations to the area, we translocated 26 bighorn sheep from Alberta, Canada to the Deadwood Region of the Black Hills. Bighorn sheep were fitted with VHF or GPS collars and monitored throughout the duration of the study (Feb 2015–Jan 2017). Our objectives were to evaluate movement patterns post-release of bighorn sheep in the translocated Deadwood bighorn sheep herd. We utilized 3 types of home-range analyses based on collar data; kernel density estimation (KDE), minimum convex polygon (MCP), and Brownian Bridge Movement Models (BBMM) were used to estimate home-ranges year 1, year 2, and for the duration of the study. Home-range size utilizing KDE (95%; x ¯ = 41.41 km2, SE = 10.50), minimum convex polygon (95%; x ¯ = 55.73 km2, SE = 15.04), and BBMM (95%; x ¯ = 32.95 km2, SE = 4.67) differed among methods. Year 1 home-range sizes (95% BBMM; x ¯ = 40.01 km2) were larger than year 2 (95% BBMM; x ¯ = 4.08 km2) home-range sizes. Travel distances were also larger in year 1 ( x ¯ = 431.80 km) than year 2 ( x ¯ = 368.77 km). Our results indicate that after an acclimation period, which included individual dispersal, the translocated Deadwood bighorn sheep herd settled into smaller home-ranges near the release site. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
32. Activity and Ranging Behavior of Leopard Cats (Prionailurus bengalensis) in an Oil Palm Landscape
- Author
-
Muhammad Silmi, Kharisma Putra, Ali Amran, Mahfud Huda, Aldino Fauzil Fanani, Birute Mary Galdikas, Prima Anggara S, and Carl Traeholt
- Subjects
leopard cat (Prionailurus bengalensis) ,oil palm plantation ,home-range ,biological pest control ,activity ,Environmental sciences ,GE1-350 - Abstract
The leopard cat (Prionailurus bengalensis) is the most widespread feline in Asia. It has been recorded in a range of habitats, including monoculture landscapes, such as oil palm plantations. Here, we report on a study on the presence, home range, activity patterns and diet of the species in an oil palm landscape to assess their viability as biological pest controller of rats. The study took place in United Plantations/PT SSS estate in Central Kalimantan, Borneo, Indonesia. From July 2014 to March 2018, we captured 11 leopard cats in purpose-built cage-traps and fitted them with VHF radio-transmitters. They were tracked for a 44 months study period, during which we collected a total of 2.031 GPS locations used for estimating the respective cats’ activities and home-ranges. The cats are strictly nocturnal and prefer to hide and rest in thick bush, primarily consisting of sword-fern (Nephrolepis sp.) during day-time, but forage both on the ground and in the palm canopy at night. The average home range (95% FK) for male leopard cats is 1.47 km2 (n = 7; SD = 0.62 km2) with slightly smaller home range for females at 1.29 km2 (n = 4; SD = 0.28 km2). All individuals studied were recorded strictly within the oil palm plantation landscape, although mangrove forest habitat makes up 7% of the greater plantation landscape. In conclusion, leopard cats survive and reproduce well in oil palm habitats and are effective biological controllers of rats that can replace the traditionally used expensive and environmentally polluting chemical rat poisons.
- Published
- 2021
- Full Text
- View/download PDF
33. Characterizing primate home‐ranges in Amazonia: Using ferns and lycophytes as indicators of site quality.
- Author
-
Cárdenas Ramírez, Glenda Gabriela, Jones, Mirkka M., Heymann, Eckhard W., and Tuomisto, Hanna
- Subjects
NUMBERS of species ,HABITATS ,LYCOPHYTES ,PRIMATES ,ANIMAL populations ,FERNS - Abstract
Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
34. Unsustainable anthropogenic mortality disrupts natal dispersal and promotes inbreeding in leopards.
- Author
-
Naude, Vincent N., Balme, Guy A., O'Riain, Justin, Hunter, Luke T.B., Fattebert, Julien, Dickerson, Tristan, and Bishop, Jacqueline M.
- Subjects
- *
LEOPARD , *SOUTH Africans , *PHILOPATRY , *IN situ processing (Mining) , *BEHAVIOR , *ANIMAL mortality , *CARNIVOROUS animals - Abstract
Anthropogenic mortality of wildlife is typically inferred from measures of the absolute decline in population numbers. However, increasing evidence suggests that indirect demographic effects including changes to the age, sex, and social structure of populations, as well as the behavior of survivors, can profoundly impact population health and viability. Specifically, anthropogenic mortality of wildlife (especially when unsustainable) and fragmentation of the spatial distribution of individuals (home‐ranges) could disrupt natal dispersal mechanisms, with long‐term consequences to genetic structure, by compromising outbreeding behavior and gene flow. We investigate this threat in African leopards (Panthera pardus pardus), a polygynous felid with male‐biased natal dispersal. Using a combination of spatial (home‐range) and genetic (21 polymorphic microsatellites) data from 142 adult leopards, we contrast the structure of two South African populations with markedly different histories of anthropogenically linked mortality. Home‐range overlap, parentage assignment, and spatio‐genetic autocorrelation together show that historical exploitation of leopards in a recovering protected area has disrupted and reduced subadult male dispersal, thereby facilitating opportunistic male natal philopatry, with sons establishing territories closer to their mothers and sisters. The resultant kin‐clustering in males of this historically exploited population is comparable to that of females in a well‐protected reserve and has ultimately led to localized inbreeding. Our findings demonstrate novel evidence directly linking unsustainable anthropogenic mortality to inbreeding through disrupted dispersal in a large, solitary felid and expose the genetic consequences underlying this behavioral change. We therefore emphasize the importance of managing and mitigating the effects of unsustainable exploitation on local populations and increasing habitat fragmentation between contiguous protected areas by promoting in situ recovery and providing corridors of suitable habitat that maintain genetic connectivity. [ABSTRACT FROM AUTHOR]
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- 2020
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35. Spatial and temporal movement of the Bearded Vulture using GPS telemetry in the Himalayas of Nepal.
- Author
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Subedi, Tulsi R., Pérez‐García, Juan M., Sah, Shahrul A.M., Gurung, Sandesh, Baral, Hem S., Poudyal, Laxman P., Lee, Hansoo, Thomsett, Simon, Virani, Munir Z., and Anadón, José D.
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VULTURES ,MOUNTAINS ,TELEMETRY - Abstract
This study addresses for the first time the movement patterns of the globally near‐threatened Bearded Vulture Gypaetus barbatus in its most important stronghold, the high‐altitude mountain ranges of Asia. Tracked individuals (n = 8) in the Annapurna Himalayan range (Nepal) foraged over a vast range of 60 715.9 km2 and our results indicated age‐class differences in the use of space. Territorial adults showed very small annual home‐ranges (K90 = 150.3 km2), whereas immatures wandered extensively and covered vast ranges of the mountains (K90 = 23 930.8 km2). For adults and immatures, these values are notably larger than the other two studied populations in the world (Pyrenees and South Africa). This suggests that the studied Annapurna population might exhibit lower breeding density than in the Pyrenees or South Africa, possibly due to lower food availability. [ABSTRACT FROM AUTHOR]
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- 2020
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36. Evaluating cropland in the Canadian prairies as an ecological trap for the endangered Burrowing Owl Athene cunicularia.
- Author
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Scobie, Corey A., Bayne, Erin M., and Wellicome, Troy I.
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FARMS ,OWLS ,PRAIRIES ,GROWING season ,LANDSCAPE changes ,GRASSLANDS ,BIRD declines ,FISH migration - Abstract
Anthropogenic development may influence the choices animals make and their resulting reproductive success and survival. If such choices are maladaptive, the impact of anthropogenic change can be catastrophic to small or declining populations. Over the past century, Canada's prairie landscapes have been altered dramatically, with over two‐thirds of its native grasslands now having been converted to cropland. The decline of the endangered Burrowing Owl Athene cunicularia population is assumed to have resulted from this landscape change, yet no causal link has been demonstrated. One hypothesis to explain this population decline is that owls get caught in an ecological trap, whereby they prefer to establish nests at the start of each breeding season in landscapes that later confer lower reproductive success. Agricultural landscapes represent a plausible potential ecological trap because the short and sparse vegetation in annual crops (seeded each spring) is predicted to be attractive nesting/foraging habitat for Burrowing Owls when they arrive from northward migration, yet crops become substantially taller and denser over the growing season so prey are predicted to become less accessible by the time broods have hatched. We tested this ecological trap hypothesis in a 3‐year study, involving 379 Burrowing Owl pairs, across the agricultural landscapes of southern Alberta and Saskatchewan. In support of the hypothesis, Burrowing Owls did prefer to settle in breeding home‐ranges that contained a higher proportion of cropland, and their prey‐delivery rates during brood‐rearing were lower at nests with a higher proportion of cropland growing in the surrounding landscape. However, in contradiction to a key prediction, the number of fledglings produced (range = 0–9) was higher, not lower, for pairs with more actively growing cropland in their landscapes. Therefore, the decline of the Burrowing Owl in Canada does not appear to result from cropland forming an ecological trap during the breeding season. We also found a significant positive relationship between the amount of summer fallow within Burrowing Owl home‐ranges and the quantity of vertebrate prey delivered to the nest and the number of juveniles fledged, highlighting the importance of this declining land use in raptor conservation. [ABSTRACT FROM AUTHOR]
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- 2020
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37. Influence of environmental variables on abundance and movement of bonefish (Albula vulpes) in the Caribbean Sea and a tropical estuary of Belize and Mexico.
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Perez, Addiel U., Schmitter-Soto, Juan J., Adams, Aaron J., and Herrera-Pavón, Roberto L.
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RED fox ,ESTUARIES ,MARK & recapture (Population biology) ,MULTIPLE regression analysis ,COASTAL development ,LUNAR phases - Abstract
Bonefish (Albula vulpes) is a socioeconomically important species that supports a data-poor recreational fishery in developing countries. Understanding how environmental variables influence its abundance and movement is important for better decision-making. This study used mark-recapture to examine the association between abiotic (temperature, salinity, wind speed, tides moon phase, and sediment coarseness) and biotic (presence of predators and bottom vegetation) variables with bonefish movement and abundance in Corozal-Chetumal bay and the adjacent Caribbean coast of southern Mexico and northern Belize. We used seines to capture bonefish, marked 9657 using dart tags and recaptured 595 fish (6.2% recapture rate) during 16 sample periods between January 2016 and February 2018. Marked bonefish size ranged 19.5–56.4 cm and recaptured 23.9–49.4 cm. Total abundance for each seine sample and distance between mark and recapture locations were used in two separate multiple stepwise regression analyses. Movement was negatively associated with temperature and predator presence, while sediment coarseness and moon phase were positively associated. Temperature increases were associated with short-distance movements. Temperature decreases and high-illumination lunar phases were associated with longer-distance movement and likely related to spawning migrations. Presence of predators, like barracuda, was associated with low bonefish abundances and was likely an adaptive response to form multiple schools of low density by bonefish to avoid predation. These spatiotemporal movement and abundance patterns are recommended to be taken into account in fisheries and protected areas management and to inform the decision-making process in urban and tourism development in coastal habitats. [ABSTRACT FROM AUTHOR]
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- 2019
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38. Nearby night lighting, rather than sky glow, is associated with habitat selection by a top predator in human-dominated landscapes
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Barrientos Yuste, Rafael, Vickers, Winston, Longcore, Travis, Abelson, Eric S., Dellinger, Justin, Waetjen, David P., Fandos Guzmán, Guillermo, Shilling, Fraser M., Barrientos Yuste, Rafael, Vickers, Winston, Longcore, Travis, Abelson, Eric S., Dellinger, Justin, Waetjen, David P., Fandos Guzmán, Guillermo, and Shilling, Fraser M.
- Abstract
Funding / Acknowledgements: Programa de Becas Complutense del Amo 2020–21. This publication is based upon work supported by NASA under award No. 80NSSC22M0008 from the Science Activation Program and by California Department of Transportation under contract No. 65A0766 (T.L.) Marie Skłodowska-Curie grant agreement No 847635. Funding for data collection was provided by an array of entities over 20 years, including CDFW Federal Aid and Wildlife Restoration Grant(s) F17AF00236 and F19AF00291; ; California State Parks, The Nature Conservancy and multiple Foundations, non-profits and private individuals., Artificial light at night (ALAN) is increasing in extent and intensity across the globe. It has been shown to interfere with animal sensory systems, orientation and distribution, with the potential to cause significant ecological impacts. We analysed the locations of 102 mountain lions (Puma concolor) in a light-polluted region in California. We modelled their distribution relative to environmental and human-disturbance variables, including upward radiance (nearby lights), zenith brightness (sky glow) and natural illumination from moonlight. We found that mountain lion probability of presence was highly related to upward radiance, that is, related to lights within approximately 500 m. Despite a general pattern of avoidance of locations with high upward radiance, there were large differences in degree of avoidance among individuals. The amount of light from artificial sky glow was not influential when included together with upward radiance in the models, and illumination from moonlight was not influential at all. Our results suggest that changes in visibility associated with lunar cycles and sky glow are less important for mountain lions in their selection of light landscapes than avoiding potential interactions with humans represented by the presence of nearby lights on the ground., Comunidad de Madrid, European Commission, NASA, Caltrans, Road Ecology Center, Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub
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- 2023
39. Bridging scales to understand species spatial organization
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Colombo, E. H., (0000-0003-2224-9758) Saraiva De Menezes, J. F., (0000-0003-0575-6408) Calabrese, J., Colombo, E. H., (0000-0003-2224-9758) Saraiva De Menezes, J. F., and (0000-0003-0575-6408) Calabrese, J.
- Abstract
From data we first construct a Langevin equation to describe the movement of the individuals. The ctmm1 package can be used to extract the parameters behind intrinsic dynamics of each individual (potential, diffusion coefficient, etc.). However, individuals’ home-range (i.e. the area they occupy) are also shaped by its interaction with individual nearby. For that we need to resolve the forces felt by individuals during encounters2 and then scale-up their effects. This coarse-graining process generates a PDE for the temporal evolution of the occupancy probability of a given individual. This final equation, extracted from data, provides a data-driven description of the formation and maintenance of home-ranges.
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- 2023
40. Large-scale movement patterns in a social vulture are influenced by seasonality, sex, and breeding region
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Bárdenas Reales de Navarra, Ministerio de Ciencia, Tecnología e Innovación (Colombia), Junta de Andalucía, Generalitat Valenciana, Ecotone telemetry, Ministerio de Economía y Competitividad (España), European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Morant, Jon, Arrondo, Eneko, Sánchez-Zapata, José A., Donázar, José A., Cortés-Avizanda, Ainara, Riva, Manuel de la, Blanco, Guillermo, Martínez, Félix, Oltra, Juan, Carrete, Martina, Margalida, Antoni, Oliva-Vidal, Pilar, Martínez, José M., Serrano, David, Pérez-García, Juan M., Bárdenas Reales de Navarra, Ministerio de Ciencia, Tecnología e Innovación (Colombia), Junta de Andalucía, Generalitat Valenciana, Ecotone telemetry, Ministerio de Economía y Competitividad (España), European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Morant, Jon, Arrondo, Eneko, Sánchez-Zapata, José A., Donázar, José A., Cortés-Avizanda, Ainara, Riva, Manuel de la, Blanco, Guillermo, Martínez, Félix, Oltra, Juan, Carrete, Martina, Margalida, Antoni, Oliva-Vidal, Pilar, Martínez, José M., Serrano, David, and Pérez-García, Juan M.
- Abstract
Quantifying space use and segregation, as well as the extrinsic and intrinsic factors affecting them, is crucial to increase our knowledge of species-specific movement ecology and to design effective management and conservation measures. This is particularly relevant in the case of species that are highly mobile and dependent on sparse and unpredictable trophic resources, such as vultures. Here, we used the GPS-tagged data of 127 adult Griffon Vultures Gyps fulvus captured at five different breeding regions in Spain to describe the movement patterns (home-range size and fidelity, and monthly cumulative distance). We also examined how individual sex, season, and breeding region determined the cumulative distance traveled and the size and overlap between consecutive monthly home-ranges. Overall, Griffon Vultures exhibited very large annual home-range sizes of 5027 ± 2123 km2, mean monthly cumulative distances of 1776 ± 1497 km, and showed a monthly home-range fidelity of 67.8 ± 25.5%. However, individuals from northern breeding regions showed smaller home-ranges and traveled shorter monthly distances than those from southern ones. In all cases, home-ranges were larger in spring and summer than in winter and autumn, which could be related to difference in flying conditions and food requirements associated with reproduction. Moreover, females showed larger home-ranges and less monthly fidelity than males, indicating that the latter tended to use the similar areas throughout the year. Overall, our results indicate that both extrinsic and intrinsic factors modulate the home-range of the Griffon Vulture and that spatial segregation depends on sex and season at the individual level, without relevant differences between breeding regions in individual site fidelity. These results have important implications for conservation, such as identifying key threat factors necessary to improve management actions and policy decisions.
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- 2023
41. Which bird traits most affect the goodness-of-fit of species distribution models?
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Morelli, Federico, Benedetti, Yanina, Stanford, Jesse, Jerzak, Leszek, Tryjanowski, Piotr, Perna, Paolo, and Santolini, Riccardo
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SPECIES distribution , *ECOSYSTEM management , *BIRD breeding , *STATISTICAL models , *STATISTICS , *BIRD populations - Abstract
[Display omitted] • Species distribution models (SDMs) combine data on species occurrence and environment. • The SDM performance predicting species occurrence can be measured as the goodness-of-fit. • We compared the goodness-of-fit (GOF) of SDMs among 56 breeding bird species. • GOF was unrelated to species home-range, body mass, detectability or diet-specialization. • SDMs were more accurate for habitat-specialist species, mainly for grassland species. Species distribution models (SDMs) are numerical tools that combine species occurrence (or abundance) data with environmental variables, to predict the species' distribution spatially. SDMs are increasingly used for purposes of conservation planning and management of ecosystems. The model performance can be measured as the goodness-of-fit (GOF), which describes how well it fits (e.g., the discrepancy between the statistical model and the data observed). However, there is still a need for a deeper understanding of the ecological characteristics of the modelled species which can affect the accuracy of those models. Here, we compared the goodness-of-fit of SDMs, considering several ecological characteristics of 56 bird species: Most frequently used environment, body mass, home-range, species specialization index (SSI), diet specialization and detectability. All SDMs were performed on the same dataset, and the relative frequency of each species was also incorporated to account for occurrence heterogeneity. GOF of SDMs was not significantly correlated with species' frequency, home-range, body mass, degree of detectability or level of diet specialization. Overall, the birds with more accurate SDMs (GOF) were species of grasslands and the GOF was positively associated with SSI, indicating that more habitat-specialized species are better predictable. Our findings suggest that is important to focus not only on statistical issues potentially related to model performance but also on ecological characteristics of single species because can improve the performance of modellistic procedures, increasing their predictive power. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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42. Movement ecology of Afrotropical birds: Functional traits provide complementary insights to species identity.
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Habel, Jan Christian, Tobias, Joseph A., and Fischer, Christina
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BIRD ecology ,SPECIES ,FARMS ,HABITATS - Abstract
Effects of anthropogenic activities on habitats and species communities and populations are complex and vary across species depending on their ecological traits. Movement ecology may provide important insights into species' responses to habitat structures and quality. We investigated how movement behavior across a human‐modified landscape depends on species identity and species traits, with particular focus on habitat specialization, feeding guilds, and dispersal behavior. We tracked 34 individuals of nine Afrotropical bird species during three years in an anthropogenic riparian landscape of East Africa. We investigated whether species' functional traits predicted their habitat use and movement behavior better than species' identities. Our results indicate that habitat specialists mainly occur in dense riparian thickets, while habitat generalists do occur in agricultural land. Home‐ranges of omnivorous habitat generalists are larger than of frugivorous and insectivorous generalists and omnivorous and insectivorous specialists. Movement speed was highest in settlement areas for all species, with activity peaks during morning and afternoon for habitat specialists. Our results reveal that functional traits and species identity provide complementary insights into responses of organisms to habitat structures and habitat quality. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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43. Development of a Web Application Algorithm for the Analysis and Visualization of Marine Animal Home Range Using R Shiny.
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Han, Jae-Rim, Kim, Tae Hoon, Choi, Hyun Woo, and Han, Hyeon Gyeong
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HOME range (Animal geography) , *MARINE animals , *WEB-based user interfaces , *WEB development , *ANIMAL ecology - Abstract
Han, J.-R.; Kim, T.H.; Choi, H.W., and Han, H.G., 2023. Development of a web application algorithm for the analysis and visualization of marine animal home range using R Shiny. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 250-254. Charlotte (North Carolina), ISSN 0749-0208. Recently, marine animals have been experiencing significant suffering due to marine waste. Therefore, continuous tracking and management of marine animals, as well as understanding their behavior patterns, have to study for effectively managing the marine ecosystem. This paper aims to design and implement a responsive system that can manage and support marine ecosystems by analyzing the home range and visualizing data of marine animals, including their location information. To achieve this objective, we developed an algorithm that utilizes open-source R-based methods such as minimum convex hull polygon and kernel density to estimate home range. Additionally, a Shiny-based reactivity web application was implemented to visualize the results on a map. As a result, researchers in the field of marine animals and marine ecology were able to analyze behavior patterns using attribute conditions such as the type and location information transmission time of marine animals without a separate GIS analysis program. In addition, the analysis results were visually presented on a map to enable a clear and intuitive comprehension of the movements of marine animals. If the system is continuously developed through research in the future, we expect to efficiently manage the marine ecosystem and provide even more insightful information. [ABSTRACT FROM AUTHOR]
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- 2023
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44. First results from the releases of Cinereous Vultures (Aegypius monachus) aiming at re-introducing the species in Bulgaria – the start of the establishment phase 2018–2022
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Ivelin Ivanov, Emilian Stoynov, Georgi Stoyanov, Elena Kmetova–Biro, Jovan Andevski, Hristo Peshev, Simeon Marin, Julien Terraube, Lachezar Bonchev, Iliyan Stoev, Jose Tavares, Franziska Loercher, Marleen Huyghe, Zlatka Nikolova, Nadya Vangelova, Stamen Stanchev, Emanuil Mitrevichin, Elena Tilova, and Atanas Grozdanov
- Subjects
survival rate ,evaluation in conservation management ,Sarcopterygii ,Accipitriformes ,release from aviary ,Aegypius ,Sinite Kamani Nature Park ,Amniota ,Aegypius monachus ,Vrachanski Balkan Nature Park ,Kotlenska Planina SPA ,re-introduction strategy ,Gnathostomata ,Accipitridae ,Animalia ,Chordata ,Ecology, Evolution, Behavior and Systematics ,Vertebrata ,Tetrapoda ,Ecology ,release by hacking (artificial nest) ,home-range ,artificial nest platforms ,Biota ,Osteichthyes ,raptor ,Balkan Mountains ,Aves - Abstract
The current work presents the preliminary results of the Cinereous Vulture (Aegypius monachus) releases in the Balkan Mountains in 2018–2022, aiming at the species re-introduction in Bulgaria, where it was listed as locally extinct since 1985. The first imports and releases of Cinereous Vultures in Bulgaria started in 2018. Until mid-2022, 72 individuals were released in the Eastern Balkan Mountains (Kotlenska Planina SPA and Sinite Kamani Nature Park) and Vrachanski Balkan Nature Park. Of them, 63 immatures imported from Spain were released from aviaries and nine juveniles captive-bred in European zoos were released by hacking (fledging from an artificial nest). We compared the success in survival and establishment between the different release sites and methods used to adjust the ongoing technics and tactics and to support knowledge improvement for future similar projects. From the nine Cinereous Vultures released by hacking, the results were as follows: 1.00 fledging success, but only 0.22 survival in the first six months – combined period of acclimation, first migration and the first winter. All survivors from that period reached maturity into the wild, but all emigrated from the release site and settled elsewhere. Of the 63 individuals released by aviaries, 32 individuals were released in the Eastern Balkan Mountains (18 individuals are still alive – 0.56 survival; 14 individuals settled in the area, which accounts for 0.44 of all released birds and 0.78 of the survivors). Thirty-one individuals were released in Vrachanski Balkan Nature Park (23 individuals are still alive – 0.74 survival; 22 individuals settled in the area – 0.71 of all released birds and 0.96 of the survivors). Based only on aviary method comparison, the settling of the individuals in the release area was alike in the two sites. However, the Vrachanski Balkan Nature Park performed better in survival – both in acclimation and establishment periods. While comparing the release methods – hacking and release from the aviary – the following results were observed: the survival rate during acclimation was 0.86. Due to more considerable losses during the first migration and dispersal in the individuals released by hacking, the survival rate of 0.22 was significantly lower compared to 0.73 for the birds released from the aviary. Additionally, in both methods, a similar pattern in the first winter and spring migration dispersal was observed. Although the survival was equal in the released-by-hacking or aviary birds after the first year onwards, it is essential to note that the emigration of the hacked birds from the release site was 1.00. In comparison, the birds released from aviaries largely remained and settled in the release area (> 0.77 of the survivors). The cost of release and related acclimation, settling, dispersal and the first winter was the greatest: 0.12–0.17 per period, or cumulatively, it was about 0.27. Survival increased and stabilised to > 0.90 after the first year in the wild and reached nearly 1.00 after two years in the wild onwards. Two distinct nuclei of the Cinereous Vulture were established along the Balkan Mountains – the Eastern Balkan Mountains with 18–23 individuals and four formed pairs using a territory of about 642.74 km2 – 95% home range and 85.72 km2 – 50% core area with center being the town of Kotel; and Vrachanski Balkan Nature Park with present 23–29 individuals, of which 2–3 pairs formed so far, using a territory of about 1,143.66 km2 – 95% home range and 22.89 km2 – 50% core area with center being the village of Zgorigrad. The species readily accepted breeding in artificial nest platforms built by professional arborists on different tree species – oak, beech, sycamore and pine. The only naturally built nests were on the ground (n = 2) (unsuccessful) and in Scots Pine (n = 1) (successful). In 2021 and 2022, in each of the two sites, the first successful reproductions were recorded, which marked the return of the Cinereous Vulture as breeding species – 28 years after the last occasional record of a single breeding pair in the country and 36 years after it was officially listed as locally extinct in Bulgaria.
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- 2023
45. Evaluating interactions between space‐use sharing and defence under increasing density conditions for the group‐territorial Red‐cockaded Woodpecker Leuconotopicus borealis.
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Garabedian, James E., Moorman, Christopher E., Peterson, M. Nils, and Kilgo, John C.
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RED-cockaded woodpecker ,VORONOI polygons ,DENSITY dependence (Ecology) ,HOME range (Animal geography) ,BIRD ecology - Abstract
Information about how bird species respond to increasing density conditions through either space‐use sharing or increased territoriality, and how those changes affect fitness, is essential for effective conservation planning. We used a case study of endangered Red‐cockaded Woodpeckers Leuconotopicus borealis (RCW) to address these questions. We documented over 36 000 locations from 44 RCW groups in three density conditions on two sites in South Carolina, USA, between April 2013 and March 2015. The frequency of neighbouring group interactions differed among density conditions and was highest for high‐density groups. RCW home‐ranges and core‐areas were larger under low‐density conditions (x¯Home‐range = 88.4 ha, x¯Core‐area = 21.0 ha) than under medium (x¯Home‐range = 68.29 ha, x¯Core‐area = 16.6 ha) and high‐density (x¯Home‐range = 76.3 ha, x¯Core‐area = 18.6 ha) conditions. Neighbouring RCWs maintained overlapping home‐ranges with nearly exclusive core‐areas across density conditions, but overlap tended to increase as neighbouring group density increased. Under high‐density conditions, home‐range overlap correlated inversely with clutch size (β ± se = −0.19 ± 0.09), nestling production (β ± se = −0.37 ± 0.09) and fledgling production (β ± se = −0.34 ± 0.08). Our results indicate that RCWs dedicate more effort to territorial defence under high‐density conditions, potentially at the expense of greater foraging efficiency and time allocated to reproduction, as evidenced by reduced fitness. Large home‐range overlap indicated limited territoriality farther away from cavity trees, but the existence of exclusive core‐areas suggests that RCW groups defend habitat closer to cavity trees. Thiessen partitions used to allocate critical foraging habitat offered comprehensive habitat protection for RCW but appear flawed for spatially explicit habitat assessments because they do not accurately delineate space used by individual RCW groups. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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46. Natural flow events influence the behaviour and movement patterns of eel-tailed catfish (Tandanus tandanus) in a subtropical Queensland river.
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Burndred, Kate R., Cockayne, Bernie J., Donaldson, James A., and Ebner, Brendan C.
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- *
CATFISHES , *CATFISH behavior , *FRESHWATER fishes , *FISH locomotion , *FISH conservation - Abstract
Understanding the movement ecology of freshwater fishes, and how these patterns are affected by flow, is important for identifying key threats to populations and predicting their response to management strategies. We used acoustic telemetry to investigate the day-to-day behaviour and movement patterns of eel-tailed catfish (Tandanus tandanus) and examine how their behaviour was affected by natural changes to the flow regime in a subtropical river. Movement patterns varied within the tagged population: 29% were sedentary, 64% undertook interpool movements and 7% undertook reach-scale movements. The mean maximum distance travelled was 0.75 km (±0.33, s.e.) and the maximum distance travelled was 16.9 km downstream. Fish moved upstream and downstream between pools mostly at dawn and dusk, presumably to feed in riffles. Most interpool movements were undertaken during low-flow conditions (<0.2 m s–1 and <6.0 m3 s–1). Generally, the population responded inconsistently to flow events; however, the greatest movement response was detected during the first post-winter flow. Although fish preferred to move on an event fall, several fish continued to move throughout the study reach under baseflow conditions. Management strategies protecting low-flow conditions that maintain connectivity between daytime refuges and riffles may be important for the species' conservation. The effective delivery of post-winter flow events, particularly in perennial systems, is likely to provide critical dispersal opportunities and aid long-term population viability. We investigated the behaviour and movement patterns of eel-tailed catfish, Tandanus tandanus , using acoustic telemetry in an unregulated subtropical river. Generally, fish undertook inter-pool movements under low flow conditions; however, the greatest movement response was detected during the first post-winter flow event. Results can assist conservation and management of endangered populations in south-eastern Australia. Photo by Queensland Department of Agriculture and Fisheries. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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47. Complex movement patterns by foraging loggerhead sea turtles outside the breeding season identified using Argos‐linked Fastloc‐Global Positioning System.
- Author
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Dujon, Antoine M., Schofield, Gail, Lester, Rebecca E., Papafitsoros, Kostas, and Hays, Graeme C.
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LOGGERHEAD turtle , *FORAGING behavior , *ANIMAL breeding , *ANIMAL wintering , *HABITAT selection - Abstract
Abstract: We used Argos‐linked Fastloc‐Global Positioning System (Argos‐linked Fastloc‐GPS) satellite tags to investigate how loggerhead sea turtles use neritic foraging habitats at multiple scales. Out of 24 turtles, six individuals used more than one foraging site, with all sites being separated by >25 km. These six individuals used up to four sites, remaining at each site for a mean of 150 days and returning to the same site a minimum of 52 days later. The other 18 turtles remained in a single site. The area within sites was not used uniformly, with 15 out of 24 turtles exhibiting complex movement patterns within and amongst up to five focal patches, which were typically 0.1–5.0 km apart within a single site. Movements between sites and patches might sometimes have reflected overwintering behaviour; however, similar movement patterns occurred at multiple times of the year, suggesting other factors were also involved. Use of multiple sites and patches might be driven by differences in resource availability, such as food and/or night‐time refuges, competition, or exploratory movement to investigate or locate alternative patches. We confirmed competition via direct visual observations of aggressive interactions between individuals at one foraging patch. Our results illustrate the importance of standardizing data to the same number of locations per day and night to accurately delineate key areas used by turtles or for evidence‐based marine protected area planning. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
48. Home-range size of the European wildcat (Felis silvestris silvestris): a report from two areas in Central Italy.
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Anile, Stefano, Bizzarri, Lolita, Lacrimini, Moreno, Sforzi, Andrea, Ragni, Bernardino, and Devillard, Sebastien
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EUROPEAN wildcat , *BROWNIAN bridges (Mathematics) , *NOCTURNAL animals , *POPULATION density , *POPULATION geography - Abstract
Although the behavioural ecology of the European wildcat (Felis silvestris silvestris) has been studied in several European countries, its home-range size is still poorly known due to elusive behaviour of the species living in typically low population densities. In our study, 11 wildcats from two distinct areas, the Maremma Regional Park (Tuscany; 3 males and 1 female) and the Paradiso di Pianciano Estate (Umbria; 6 males and 1 female), both located in Central Italy, were studied by means of classical VHF radio-tracking. Home ranges were calculated by means of the Brownian bridge movement model (BBMM). Variables significantly affecting home-range size were: study area, gender and the interaction between gender * age. The potential effect of the reproductive season and the nocturnal period was not supported. The main findings indicate that: (1) home-range sizes in Tuscany were larger than those in Umbria; (2) home-range size was positively related to the age of individuals; (3) males exploited larger home ranges than females in all age-classes except for the sub-adult age-class; this latter pattern has never emerged from any previous wildcat radio-telemetry study. Population density, different management regimes in the areas considered and the local abundance of prey may explain differences in home-range sizes between the study areas. The estimated home ranges of wildcats in Umbria were slightly larger than those reported across Europe, while those calculated in the Tuscan study area were significantly greater. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
49. Translocation and long-term monitoring of threatened thin-spined porcupines (Chaetomys subspinosus) on the Brazilian coast.
- Author
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Melo-Dias, Mateus, Rocha, Mariana F., Dalfior, Izabelle C.D., Bissa, Luan, Marcial, Thiago, Secco, Helio, Passamani, Marcelo, and Rosa, Clarissa
- Subjects
PORCUPINES ,RODENT populations ,HABITAT selection ,TROPICAL forests ,FOREST plants ,COASTS - Abstract
With increasing infrastructural development along Brazil's coast, environmental regulation measures are becoming increasingly necessary in the face of the damage caused by large projects that impact tropical forests. Brazilian legislation supports implementation of translocation programs for impacted fauna, especially threatened species such as the thin-spined porcupine Chaetomys subspinosus (Rodentia, Erethizontidae). Thus, we present a case study of a pioneer translocation program for the thin-spined porcupine in southeastern Brazil. We aimed to analyze the home-range and habitat selection of three translocated porcupines and one resident individual. In addition, we analyzed the success of the translocations. The porcupines were monitored by radiotelemetry for 3–16 months from October 2015 to March 2017 in a mosaic landscape of restinga forests (sandbank forest vegetation) within a eucalyptus matrix. The translocated porcupines had considerably larger home-ranges (14.29–18.36 ha, minimum convex polygon method – MCP) than did the resident animal (1.22 ha – MCP). We observed stabilization in the home-range size curves of the translocated females in the 7th − 9th month of monitoring. All translocated individuals achieved permanence within a preselected area, indicating adaptation to the new area. In addition, individuals showed a clear preference for restinga forests over drained eucalyptus plantations. Thus, our results demonstrate the feasibility of thin-spined porcupine translocations and the importance of maintaining restinga forest remnants outside of protected areas for the conservation and permanence of viable populations of this rodent. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. Experimentally testing the response of feral cats and their prey to poison baiting
- Author
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Doherty, Tim, Hall, ML, Parkhurst, B, Westcott, V, Doherty, Tim, Hall, ML, Parkhurst, B, and Westcott, V
- Abstract
Context: Feral cats, Felis catus, have caused the decline and extinction of many species worldwide, particularly on islands and in Australia where native species are generally naïve to the threat of this introduced predator. Effectively reducing cat populations to protect wildlife is challenging because cats have a cryptic nature, high reproductive rate and strong reinvasion ability. Aims: We experimentally tested the response of feral cats and their native prey to an Eradicat® poison baiting program at a conservation reserve. Methods: Baits were distributed by hand along roads and tracks every 50 m (∼10 baits km-2). We used camera traps to monitor the response of cats to baiting using a repeated before-after, control-impact design over 6 years. We also measured introduced rabbit, Oryctolagus cuniculus, activity by using sand pads and small mammal and reptile captures by using pitfall trapping. Key results: Dynamic occupancy modelling showed only modest effects of baiting on cats in 2 of 6 years, with occupancy in the baited area decreasing from 54% to 19% in 2014 (-35%) and from 89% to 63% in 2017 (-26%). Baiting effectiveness was not related to antecedent rainfall or prey availability. Bait availability was reduced by non-target interference; 73% of 41 monitored baits were removed by non-target species. We found no evidence for persistent changes in small mammal or reptile capture rates in the baited area relative to the unbaited area over the life of the project. Conclusions: Relatively low baiting density and non-target interference with baits are likely to have reduced baiting efficacy. Further testing and refinement of ground baiting is needed, including trialling higher baiting densities and/or frequencies. Implications: We highlight key areas for future research that should benefit feral cat management not only in Australia, but also on the many islands worldwide where cats threaten native wildlife.
- Published
- 2022
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