36 results on '"Broekhuis F"'
Search Results
2. Understanding the effects of seasonal variation in prey availability on prey switching by large carnivores
- Author
-
Vettorazzi, M., Mogensen, N., Kaelo, B., Broekhuis, F., Vettorazzi, M., Mogensen, N., Kaelo, B., and Broekhuis, F.
- Abstract
Optimal foraging theory predicts that carnivores select prey species based on intrinsic factors, such as body size, vulnerability, and abundance. Prey abundance can vary significantly, especially when prey species move in and out of an area en masse in search of food. However, little is known about how these resource pulses influence the prey profiles of large carnivores. Using data on lion (Panthera leo) and cheetah (Acinonyx jubatus) kills in the Maasai Mara in Kenya, we investigate whether changes in prey abundance, as a result of a mass annual migration of herbivores, influence the prey profiles of these two carnivore species. Furthermore, for cheetah we investigate whether there are sex-specific differences in prey profiles in response to changes in prey abundance. Using data from 387 lion kills and 220 cheetah kills (160 female and 60 male), we found that changes in prey abundance had a strong influence on prey profiles, but that for cheetahs this varied by sex and social grouping. More specifically, during the migration, when there is an influx of wildebeest (Connochaetes taurinus), lions and male cheetah (particularly those in coalitions) were more likely to feed on wildebeest than out of the migration. In addition, when wildebeest were less abundant, lions switched to buffalo (Syncerus caffer). Overall, the breadth of the prey profiles was narrower during the migration compared to out of the migration but this was most significant for lions and coalitions of male cheetahs. These changes in prey profiles could have an impact on herbivore dynamics, human-wildlife conflict and ecological interactions more broadly. Through the detailed characterisation of prey profiles, we contribute to the understanding of predator–prey dynamics and trophic interactions in complex, multi-species ecosystems and illustrate the importance of taking into account inter- and intraspecific variations in predators when modelling predator–prey dynamics.
- Published
- 2022
3. Density and habitat use of lions and spotted hyenas in northern Botswana and the influence of survey and ecological variables on call-in survey estimation
- Author
-
Cozzi, G., Broekhuis, F., McNutt, J. W., and Schmid, B.
- Published
- 2013
- Full Text
- View/download PDF
4. Predators and pastoralists: how anthropogenic pressures inside wildlife areas influence carnivore space use and movement behaviour
- Author
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Broekhuis, F., primary, Madsen, E. K., additional, and Klaassen, B., additional
- Published
- 2019
- Full Text
- View/download PDF
5. Density and habitat use of lions and spotted hyenas in northern Botswana and the influence of survey and ecological variables on call-in survey estimation
- Author
-
Cozzi, G., Broekhuis, F., McNutt, J., Schmid, B., Cozzi, G., Broekhuis, F., McNutt, J., and Schmid, B.
- Abstract
Top predators significantly impact ecosystem dynamics and act as important indicator species for ecosystem health. However, reliable density estimates for top predators, considered necessary for the development of management plans and ecosystem monitoring, are challenging to obtain. This study aims to establish baseline density estimates for two top predators, spotted hyena and lion, in the Okavango Delta in northern Botswana. Using calling stations, we surveyed free-ranging populations of the two species and investigated methodological variables that might influence results about distributions and densities, including habitat type, seasonality, and different types of playback sounds. Calling stations were distributed over a survey area of approximately 1,800km2 characterized by three major habitat types: mopane woodland, floodplain and mixed acacia sandveld. Results indicate spotted hyenas were evenly distributed independent of habitat type and season throughout the survey area with an overall density estimate of 14.4 adults/100km2. In contrast, lion distribution and density varied significantly with habitat and season. Lion density in the prey-poor mopane woodland was near zero, while in the comparatively prey-rich floodplains it was estimated at 23.1 individuals/100km2 resulting in a weighted average density of 5.8 individuals/100km2 across the entire study area. In testing the effect of varying playback sounds we found that both species were significantly more likely to respond to calls of conspecifics. Our results show how several methodological variables may influence density estimates and emphasize the importance of standardized calling-station survey methods to allow consistent replication of surveys and comparison of results that can be used for landscape-scale monitoring of large predator species
- Published
- 2018
6. Niche segregation by cheetah (Acinonyx jubatus) as a mechanism for co-existence with lion (Panthera leo) and spotted hyaena (Crocuta crocuta)
- Author
-
Broekhuis, F and Macdonald, D
- Subjects
Behaviour (zoology) ,Ecology (zoology) ,Biology ,Zoological sciences - Abstract
Intraguild competition and predation have been recognised as important ecological factors influencing the population dynamics of carnivores. The effects of these interactions are often asymmetrical due to a size-related dominancy hierarchy. However, it has been suggested that competitively subordinate carnivores can minimise the costs of predation and competition through spatial and temporal avoidance. Here I investigate the ecological and behavioural mechanisms by which cheetahs (Acinonyx jubatus) coexist with competitively stronger lions (Panthera leo) and spotted hyaenas (Crocuta crocuta). Fieldwork was carried out in the Okavango Delta, northern Botswana, between October 2008 and August 2011. A total of 20 Global Positioning System (GPS) radio-collars were fitted on all known cheetahs (n=6), lion prides (n=5) and spotted hyaena clans (n=6) in the study area (approx. 3 000 km2). Pre-programmed radio-collars recorded locations and activity continuously for each individual and these data were complemented with direct behavioural observations. Cheetah data were analysed with respect to the temporal and spatial likelihood of encountering lions and spotted hyaenas. Results suggest that the response to the risks posed by other predators is species-specific, habitat-specific and dependent on the immediacy of the risk. Resource partitioning was not the main mechanism for coexistence as cheetahs overlapped extensively with lions and spotted hyaenas in time, space and habitat use. Instead, cheetahs adjusted their spatial distribution in response to immediate risks or adapted their habitat use depending on their vulnerability (e.g. behaviours such as feeding or with differing levels of moonlight at night). In general, cheetah temporal and spatial distribution is a hierarchal process, firstly driven by resource acquisition and thereafter fine-tuned by predator avoidance. In addition, habitat heterogeneity seemed to be key in facilitating coexistence. Understanding the behavioural mechanisms that interacting apex predators adopt to regulate these negative interactions could be crucial to carnivore conservation, especially as human-related habitat loss is forcing species into ever smaller areas.
- Published
- 2016
7. Disappearing spots: The global decline of cheetah and what it means for conservation
- Author
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Durant, S, Mitchell, N, Groom, R, Pettorelli, N, Ipavec, A, Jacobson, A, Woodroffe, R, Böhm, M, Hunter, L, Becker, M, Broekhuis, F, Bashir, S, Andresen, L, Aschenborn, O, Beddiaf, M, Belbachir, F, Belbachir-Bazi, A, Berbash, A, Brandao de Matos Machado, I, Breitenmoser, C, Chege, M, Cilliers, D, Davies-Mostert, H, Dickman, A, Ezekiel, F, Farhadinia, M, Funston, P, Henschel, P, Horgan, J, de Iongh, H, Jowkar, H, Klein, R, Lindsey, P, Marker, L, Marnewick, K, Melzheimer, J, Merkle, J, Msoka, J, Msuha, M, O'Neill, H, Parker, M, Purchase, G, Samaila, S, Saidu, Y, Samna, A, Schmidt-Küentzel, A, Selebatso, E, Sogbohossou, E, Soultan, A, Stone, E, van der Meer, E, van Vuuren, R, Wykstra, M, and Young-Overton, K
- Abstract
Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human–wildlife coexistence across large multiple-use landscapes.
- Published
- 2016
8. Feeding ecology of cheetahs in the Maasai Mara, Kenya and the potential for intra‐ and interspecific competition
- Author
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Broekhuis, F., primary, Thuo, D., additional, and Hayward, M. W., additional
- Published
- 2017
- Full Text
- View/download PDF
9. Sustainable development in Africa and satellites : technologies and wisdoms
- Author
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Yogo Adiguipiou, F., Adewole, F., Afrogeez, Ahlafi, A., Barnard, S. (trad.), Baureen, S., Bencherif, H., Berthe, D., Bounda, C.S., Broekhuis, F., Carlès, J., Ibn Chambas, M., Elganzori, A.M., Frost, P., Godonou, A., Govender, N., Gulemvuga, G., Itana, F., Kairo, G., Killimbe, J., Kiura, P., Lombardo, C., Luzala, P., Martinez, P., Mbile, P., Morris, J., Mouline, S., Muhammed, I., Nasr, N., Ndala, B., Ndiaye, A., Ndione, J.A., Villard Njiélé, H., Nhongonhema, R., Nyambe, I., Omonona, D., Palla, F., Payet, R.A., Rakotondraompiana, S., Ryan, P., Shaw, J., Sebogiso, O., Soumaré, M., Tandian, A., Tbini, C., Touzi, S., Rhoda Peace, T., and Lolum Zuntabawé, B.
- Subjects
CONSERVATION DE LA NATURE ,PROTECTION DE L'ECOSYSTEME ,CONSERVATION DU SOL ,AGRICULTURE ,SOL ,CATASTROPHE NATURELLE ,HYDROLOGIE ,COOPERATION TECHNIQUE ,TELEDETECTION SPATIALE ,DIVERSITE SPECIFIQUE ,TECHNOLOGIE ,CATASTROPHE INDUSTRIELLE ,MILIEU MARIN ,PECHE ,GESTION DU RISQUE ,GESTION DE L'ENVIRONNEMENT ,DEVELOPPEMENT DURABLE ,AIDE A LA DECISION - Published
- 2012
10. Feeding ecology of cheetahs in the Maasai Mara, Kenya and the potential for intra- and interspecific competition.
- Author
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Broekhuis, F., Thuo, D., and Hayward, M. W.
- Subjects
- *
CHEETAH , *HABITAT partitioning (Ecology) , *ANIMAL feeding behavior , *ANIMAL ecology ,MAASAI Mara National Reserve (Kenya) - Abstract
Competition is an important ecological factor influencing the population dynamics of carnivores especially as shifts in prey selection could have negative consequences for other members of the carnivore guild. It is therefore important to determine a species' resource requirements to help understand the potential degree and consequences of competition. Cheetahs Acinonyx jubatus compete over resources with larger carnivores, such as lions Panthera leo. While cheetahs generally favour smaller prey than lions, male cheetahs frequently occur in coalitions and are larger than solitary females. This could result in male cheetahs killing larger prey and potentially competing more directly with lions than female cheetahs. To determine the potential for both intra- and interspecific competition, we analysed data on 194 cheetah and 214 lion kills, and compared the feeding ecology of four cheetah social groups: single females, females with cubs, single males and male coalitions to that of lions in the Maasai Mara, Kenya. The results show that the greatest potential for interspecific competition is between male cheetahs, especially those in coalitions, and lions. Intraspecific competition is most likely to occur between singleton females and females with cubs. Understanding these ecological relationships is key, especially when prey become scarce. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
11. Optimal hunting conditions drive circalunar behavior of a diurnal canivore
- Author
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Broekhuis, F., Grunewalder, S., McNutt, J.W., Macdonald, D. W., Broekhuis, F., Grunewalder, S., McNutt, J.W., and Macdonald, D. W.
- Abstract
Foraging requirements and predation risk shape activity patterns and temporal behavior patterns widely across taxa. Although this has been extensively studied in small mammals, the influence of predation and prey acquisition on the activity and behavior of large carnivores has received little attention. The diurnal activity described as typical for cheetahs ( Acinonyx jubatus ) has been explained in terms of their avoidance of antagonistic interactions with other larger predators. However, a recent study revealed that cheetahs are frequently active at night, especially during periods of full moon. Being both predator and “prey” in an environment with comparatively high densities of larger and competitively dominant nocturnal predator species, we investigated whether cheetah nocturnal behavior could be explained by favorable conditions for 1) predator avoidance or 2) prey acquisition. We used a data set of continuously recorded behavior created using machine-learning techniques on behavioral data collected in the field to transform recorded 2D activity values from radio-collars into 3 distinct behavioral states (feeding, moving, and resting). We found that 32.5% of cheetah feeding behavior occurred at night and that, in the dry season, nocturnal feeding behavior was positively correlated with moonlight intensity. Our results suggest that nocturnal and circalunar behavior of cheetahs is driven by optimal hunting conditions, outweighing the risks of encountering other predators. Using novel methodology, the results provide new insights into the temporal distribution of behavior, contributing to our understanding of the importance of moonlight and season on the behavior patterns of diurnal species.
- Published
- 2014
12. Density and habitat use of lions and spotted hyenas in northern Botswana and the influence of survey and ecological variables on call-in survey estimation
- Author
-
Cozzi, G, Broekhuis, F, McNutt, J W, Schmid, B; https://orcid.org/0000-0002-8430-3214, Cozzi, G, Broekhuis, F, McNutt, J W, and Schmid, B; https://orcid.org/0000-0002-8430-3214
- Abstract
Top predators significantly impact ecosystem dynamics and act as important indicator species for ecosystem health. However, reliable density estimates for top predators, considered necessary for the development of management plans and ecosystem monitoring, are challenging to obtain. This study aims to establish baseline density estimates for two top predators, spotted hyena and lion, in the Okavango Delta in northern Botswana. Using calling stations, we surveyed free-ranging populations of the two species and investigated methodological variables that might influence results about distributions and densities, including habitat type, seasonality, and different types of playback sounds. Calling stations were distributed over a survey area of approximately 1,800 km2 characterized by three major habitat types: mopane woodland, floodplain and mixed acacia sandveld. Results indicate spotted hyenas were evenly distributed independent of habitat type and season throughout the survey area with an overall density estimate of 14.4 adults/100 km2. In contrast, lion distribution and density varied significantly with habitat and season. Lion density in the prey-poor mopane woodland was near zero, while in the comparatively prey-rich floodplains it was estimated at 23.1 individuals/100 km2 resulting in a weighted average density of 5.8 individuals/100 km2 across the entire study area. In testing the effect of varying playback sounds we found that both species were significantly more likely to respond to calls of conspecifics. Our results show how several methodological variables may influence density estimates and emphasize the importance of standardized calling-station survey methods to allow consistent replication of surveys and comparison of results that can be used for landscape-scale monitoring of large predator species.
- Published
- 2013
13. Conserving large populations of lions – the argument for fences has holes
- Author
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Creel, S., primary, Becker, M. S., additional, Durant, S. M., additional, M'Soka, J., additional, Matandiko, W., additional, Dickman, A. J., additional, Christianson, D., additional, Dröge, E., additional, Mweetwa, T., additional, Pettorelli, N., additional, Rosenblatt, E., additional, Schuette, P., additional, Woodroffe, R., additional, Bashir, S., additional, Beudels‐Jamar, R. C., additional, Blake, S., additional, Borner, M., additional, Breitenmoser, C., additional, Broekhuis, F., additional, Cozzi, G., additional, Davenport, T. R. B., additional, Deutsch, J., additional, Dollar, L., additional, Dolrenry, S., additional, Douglas‐Hamilton, I., additional, Fitzherbert, E., additional, Foley, C., additional, Hazzah, L., additional, Henschel, P., additional, Hilborn, R., additional, Hopcraft, J. G. C., additional, Ikanda, D., additional, Jacobson, A., additional, Joubert, B., additional, Joubert, D., additional, Kelly, M. S., additional, Lichtenfeld, L., additional, Mace, G. M., additional, Milanzi, J., additional, Mitchell, N., additional, Msuha, M., additional, Muir, R., additional, Nyahongo, J., additional, Pimm, S., additional, Purchase, G., additional, Schenck, C., additional, Sillero‐Zubiri, C., additional, Sinclair, A. R. E., additional, Songorwa, A. N., additional, Stanley‐Price, M., additional, Tehou, C. A., additional, Trout, C., additional, Wall, J., additional, Wittemyer, G., additional, and Zimmermann, A., additional
- Published
- 2013
- Full Text
- View/download PDF
14. Exploring habitat use by cheetahs using ecological niche factor analysis
- Author
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Pettorelli, N., primary, Hilborn, A., additional, Broekhuis, F., additional, and Durant, S. M., additional
- Published
- 2009
- Full Text
- View/download PDF
15. Density and habitat use of lions and spotted hyenas in northern Botswana and the influence of survey and ecological variables on call-in survey estimation
- Author
-
Cozzi, G., Broekhuis, F., McNutt, J., Schmid, B., Cozzi, G., Broekhuis, F., McNutt, J., and Schmid, B.
- Abstract
Top predators significantly impact ecosystem dynamics and act as important indicator species for ecosystem health. However, reliable density estimates for top predators, considered necessary for the development of management plans and ecosystem monitoring, are challenging to obtain. This study aims to establish baseline density estimates for two top predators, spotted hyena and lion, in the Okavango Delta in northern Botswana. Using calling stations, we surveyed free-ranging populations of the two species and investigated methodological variables that might influence results about distributions and densities, including habitat type, seasonality, and different types of playback sounds. Calling stations were distributed over a survey area of approximately 1,800km2 characterized by three major habitat types: mopane woodland, floodplain and mixed acacia sandveld. Results indicate spotted hyenas were evenly distributed independent of habitat type and season throughout the survey area with an overall density estimate of 14.4 adults/100km2. In contrast, lion distribution and density varied significantly with habitat and season. Lion density in the prey-poor mopane woodland was near zero, while in the comparatively prey-rich floodplains it was estimated at 23.1 individuals/100km2 resulting in a weighted average density of 5.8 individuals/100km2 across the entire study area. In testing the effect of varying playback sounds we found that both species were significantly more likely to respond to calls of conspecifics. Our results show how several methodological variables may influence density estimates and emphasize the importance of standardized calling-station survey methods to allow consistent replication of surveys and comparison of results that can be used for landscape-scale monitoring of large predator species
16. Influence of Human Hunting Strategies and Large Carnivore Presence on Population Dynamics of European Facultative Scavengers.
- Author
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Wenting E, Eikelboom JAJ, Siepel H, Broekhuis F, and van Langevelde F
- Abstract
Ungulates serve as the primary carrion source for facultative scavengers in European ecosystems. In the absence of large carnivores, such as wolves ( Canis lupus ), human hunting leftovers are the main source of carrion for these scavengers. Additionally, wild boars ( Sus scrofa ) are heavily culled in many ecosystems and are both a significant prey species for wolves as well as a key scavenger. Nowadays, wolves and wild boars are re-establishing their historical home ranges. However, it remains unclear how their presence influences the population dynamics of facultative scavengers under different scenarios of human hunting strategies. We simulated the biomass densities of all states in the trophic web including European scavengers and wolves using an ordinary differential equations (ODE) model. The presence of wolves led to a positive trend in scavenger biomass in general. However, in general, we found that plant-based resources were more important for scavenger dynamics than carrion, regardless of whether the carrion originated from human hunting or wolf predation. Only when wolves were absent but boars present, the human hunting strategy became important in determining scavenger dynamics via carrion supply. In conclusion, our model indicates that population dynamics of facultative scavengers are not mainly driven by the availability of carrion, but rather by the presence of and competition for vegetation. Furthermore, our simulations highlight the importance of adapting human hunting strategies in accordance with the re-establishment of wolf and boar as these can cause fluctuating population patterns over the years., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
17. Rangers on the frontline of wildlife monitoring: a case study on African lions in Uganda's Nile Delta.
- Author
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Braczkowski AR, Namukose L, Musobozi S, Cornille O, Mudumba T, Drileyo G, Broekhuis F, Jingo S, Asimwe B, Luhonda P, Atukwatse B, O'Bryan CJ, McCallum H, Biggs D, Gibson L, Rwetsiba A, Gopalaswamy AM, Lindsey P, and Elliot N
- Subjects
- Animals, Uganda, Animals, Wild, Conservation of Natural Resources, Rivers, Lions
- Published
- 2024
- Full Text
- View/download PDF
18. Effect of ecological and anthropogenic factors on grouping patterns in African lions across Kenya.
- Author
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Chege M, Bertola LD, De Snoo GR, Ngene S, Otieno T, Amoke I, van 't Zelfde M, Dolrenry S, Broekhuis F, Tamis W, De Iongh HH, and Elliot NB
- Abstract
Social carnivores frequently live in fission-fusion societies, where individuals that share a common territory or home range may be found alone, in subgroups, or altogether. Absolute group size and subgroup size is expected to vary according to resource distribution, but for species that are susceptible to anthropogenic pressures, other factors may be important drivers. African lions ( Panthera leo ) are the only truly social felid and lion prides are characterized by fission-fusion dynamics with social groups frequently splitting and reforming, and subgroup membership can change continuously and frequently. The number of individuals in a group can be reflective of social, ecological, and anthropogenic conditions. This dynamic behavior makes understanding lion grouping patterns crucial for tailoring conservation measures. The evolution of group living in lions has been the topic of numerous studies, and we drew on these to formulate hypotheses relating to group size and subgroup size variation. Based on data collected from 199 lion groups across eight sites in Kenya, we found that group sizes were smaller when lions were closer to human settlements, suggesting that edge effects are impacting lions at a national scale. Smaller groups were also more likely when they were far from water, and were associated with very low and very high levels of non-tree vegetation. We found significant differences between the study sites, with the Maasai Mara having the largest groups (mean ± SD = 7.7 ± 4.7, range = 1-19), and Amboseli conservation area the smallest (4.3 ± 3.5, range = 1-14). While long-term studies within a single site are well suited to thoroughly differentiate between absolute group size and subgroup size, our study provides unique insight into the correlates of grouping patterns in a vulnerable species at a national scale., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
19. Introducing African cheetahs to India is an ill-advised conservation attempt.
- Author
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Gopalaswamy AM, Khalatbari L, Chellam R, Mills MGL, Vanak AT, Thuo D, Karanth KU, and Broekhuis F
- Subjects
- Animals, India, Acinonyx
- Published
- 2022
- Full Text
- View/download PDF
20. How "science" can facilitate the politicization of charismatic megafauna counts.
- Author
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Gopalaswamy AM, Elliot NB, Ngene S, Broekhuis F, Braczkowski A, Lindsey P, Packer C, and Stenseth NC
- Subjects
- Administrative Personnel, Animals, India, Population, Endangered Species, Environmental Monitoring, Lions, Politics, Tigers
- Published
- 2022
- Full Text
- View/download PDF
21. Lions in a coexistence landscape: Repurposing a traditional field technique to monitor an elusive carnivore.
- Author
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Western G, Elliot NB, Sompeta SL, Broekhuis F, Ngene S, and Gopalaswamy AM
- Abstract
Throughout Africa, lions are thought to have experienced dramatic population decline and range contraction. The greatest declines are likely occurring in human-dominated landscapes where reliably estimating lion populations is particularly challenging. By adapting a method that has thus far only been applied to animals that are habituated to vehicles, we estimate lion density in two community areas in Kenya's South Rift, located more than 100 km from the nearest protected area (PA). More specifically, we conducted an 89-day survey using unstructured spatial sampling coupled with playbacks, a commonly used field technique, and estimated lion density using spatial capture-recapture (SCR) models. Our estimated density of 5.9 lions over the age of 1 year per 100 km
2 compares favorably with many PAs and suggests that this is a key lion population that could be crucial for connectivity across the wider landscape. We discuss the possible mechanisms supporting this density and demonstrate how rigorous field methods combined with robust analyses can produce reliable population estimates within human-dominated landscapes., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)- Published
- 2022
- Full Text
- View/download PDF
22. Landscape Dynamics (landDX) an open-access spatial-temporal database for the Kenya-Tanzania borderlands.
- Author
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Tyrrell P, Amoke I, Betjes K, Broekhuis F, Buitenwerf R, Carroll S, Hahn N, Haywood D, Klaassen B, Løvschal M, Macdonald D, Maiyo K, Mbithi H, Mwangi N, Ochola C, Odire E, Ondrusek V, Ratemo J, Pope F, Russell S, Sairowua W, Sigilai K, Stabach JA, Svenning JC, Stone E, du Toit JT, Western G, Wittemyer G, and Wall J
- Subjects
- Agriculture, Animals, Conservation of Natural Resources, Databases, Factual, Kenya, Livestock, Mammals, Spatio-Temporal Analysis, Tanzania, Animals, Wild, Biodiversity, Grassland
- Abstract
The savannas of the Kenya-Tanzania borderland cover >100,000 km
2 and is one of the most important regions globally for biodiversity conservation, particularly large mammals. The region also supports >1 million pastoralists and their livestock. In these systems, resources for both large mammals and pastoralists are highly variable in space and time and thus require connected landscapes. However, ongoing fragmentation of (semi-)natural vegetation by smallholder fencing and expansion of agriculture threatens this social-ecological system. Spatial data on fences and agricultural expansion are localized and dispersed among data owners and databases. Here, we synthesized data from several research groups and conservation NGOs and present the first release of the Landscape Dynamics (landDX) spatial-temporal database, covering ~30,000 km2 of southern Kenya. The data includes 31,000 livestock enclosures, nearly 40,000 kilometres of fencing, and 1,500 km2 of agricultural land. We provide caveats and interpretation of the different methodologies used. These data are useful to answer fundamental ecological questions, to quantify the rate of change of ecosystem function and wildlife populations, for conservation and livestock management, and for local and governmental spatial planning., (© 2022. The Author(s).)- Published
- 2022
- Full Text
- View/download PDF
23. An insight into the prey spectra and livestock predation by cheetahs in Kenya using faecal DNA metabarcoding.
- Author
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Thuo D, Broekhuis F, Furlan E, Bertola LD, Kamau J, and Gleeson DM
- Subjects
- Animals, Animals, Wild, DNA genetics, Diet, Ecosystem, Female, Kenya, Male, Acinonyx physiology, Feces chemistry, Livestock genetics, Mammals genetics, Predatory Behavior
- Abstract
Dietary composition is a fundamental part of animal ecology and an important component of population dynamics. Therefore, obtaining accurate information on what an animal consumes is important for conservation planning, especially for wild large carnivores that exist in human-dominated landscapes where they are prone to direct conflicts with local people. We used faecal DNA metabarcoding to identify the vertebrate taxa commonly predated on by cheetahs (Acinonyx jubatus) with an emphasis on domestic taxa and determine the drivers of livestock predation by cheetahs residing in the Maasai Mara and Amboseli ecosystems which are important population strongholds in southern Kenya. From 84 cheetah faeces that we analysed, a total of 14 prey taxa were identified, including birds, wild and domestic mammals. The livestock taxa identified in cheetah faeces occurred at moderate frequency (12.8%) and the results showed that livestock predation was influenced neither by the sex of the cheetah nor by season. In general, our study shows that cheetahs prey on a diverse range of prey taxa including birds, wild ungulates of various sizes and occasionally on domestic animals, and that the faecal DNA metabarcoding approach represents a valuable complement to traditional dietary analysis methods., (Copyright © 2020 Elsevier GmbH. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
24. Food from faeces: Evaluating the efficacy of scat DNA metabarcoding in dietary analyses.
- Author
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Thuo D, Furlan E, Broekhuis F, Kamau J, Macdonald K, and Gleeson DM
- Subjects
- Animals, Acinonyx physiology, DNA analysis, DNA Barcoding, Taxonomic methods, Diet veterinary, Feces chemistry
- Abstract
Scat DNA metabarcoding is increasingly being used to track the feeding ecology of elusive wildlife species. This approach has greatly increased the resolution and detection success of prey items contained in scats when compared with other classical methods. However, there have been few studies that have systematically tested the applicability and reliability of this approach to study the diet of large felids species in the wild. Here we assessed the effectiveness of this approach in the cheetah Acinonyx jubatus. We tested how scat degradation, meal size, prey species consumed and feeding day (the day a particular prey was consumed) influenced prey DNA detection success in captive cheetahs. We demonstrated that it is possible to obtain diet information from 60-day old scats using genetic approaches, but the efficiency decreased over time. Probability of species-identification was highest for food items consumed one day prior to scat collection and the probability of being able to identify the species consumed increased with the proportion of the prey consumed. Detection success varied among prey species but not by individual cheetah. Identification of prey species using DNA detection methods from a single consumption event worked for samples collected between 8 and 72 hours post-feeding. Our approach confirms the utility of genetic approaches to identify prey species in scats and highlight the need to account for the systematic bias in results to control for possible scat degradation, feeding day, meal size and prey species consumed especially in the wild-collected scats., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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25. Deconstructing compassionate conservation.
- Author
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Hayward MW, Callen A, Allen BL, Ballard G, Broekhuis F, Bugir C, Clarke RH, Clulow J, Clulow S, Daltry JC, Davies-Mostert HT, Fleming PJS, Griffin AS, Howell LG, Kerley GIH, Klop-Toker K, Legge S, Major T, Meyer N, Montgomery RA, Moseby K, Parker DM, Périquet S, Read J, Scanlon RJ, Seeto R, Shuttleworth C, Somers MJ, Tamessar CT, Tuft K, Upton R, Valenzuela-Molina M, Wayne A, Witt RR, and Wüster W
- Subjects
- Animal Welfare, Animals, Empathy, Humans, Biodiversity, Conservation of Natural Resources
- Abstract
Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public., (© 2019 Society for Conservation Biology.)
- Published
- 2019
- Full Text
- View/download PDF
26. Using GPS collars to investigate the frequency and behavioural outcomes of intraspecific interactions among carnivores: A case study of male cheetahs in the Maasai Mara, Kenya.
- Author
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Broekhuis F, Madsen EK, Keiwua K, and Macdonald DW
- Subjects
- Animals, Geographic Information Systems, Kenya, Male, Remote Sensing Technology methods, Acinonyx physiology, Animal Communication, Homing Behavior physiology, Remote Sensing Technology instrumentation, Wearable Electronic Devices
- Abstract
Intraspecific interactions between individuals or groups of individuals of the same species are an important component of population dynamics. Interactions can be static, such as spatial overlap, or dynamic based on the interactions of movements, and can be mediated through communication, such as the deployment of scent marks. Interactions and their behavioural outcomes can be difficult to determine, especially for species that live at low densities. With the use of GPS collars we quantify both static and dynamic interactions between male cheetahs (Acinonyx jubatus) and the behavioural outcomes. The 99% home-ranges of males overlapped significantly while there was little overlap of the 50% home-ranges. Despite this overlap, male cheetahs rarely came into close proximity of one another, possibly because presence was communicated through frequent visits to marking posts. The minimum distance between individuals in a dyad ranged from 89m to 196m but the average proximity between individuals ranged from 17,145 ± 6,865m to 26,367 ± 11,288m. Possible interactions took place more frequently at night than by day and occurred mostly in the 50% home-range of one individual of a dyad or where cores of both individuals overlapped. After a possible encounter male cheetahs stayed in close proximity to each other for up to 6 hours, which could be the result of a territory defence strategy or the presence of a receptive female. We believe that one of the encounters between a singleton and a 5-male coalition resulted in the death of the singleton. Our results give new insights into cheetah interactions, which could help our understanding of ecological processes such as disease transmission., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
- Full Text
- View/download PDF
27. Living on the edge: Multiscale habitat selection by cheetahs in a human-wildlife landscape.
- Author
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Klaassen B and Broekhuis F
- Abstract
Animals select habitats that will ultimately optimize their fitness through access to favorable resources, such as food, mates, and breeding sites. However, access to these resources may be limited by bottom-up effects, such as availability, and top-down effects, such as risk avoidance and competition, including that with humans. Competition between wildlife and people over resources, specifically over space, has played a significant role in the worldwide decrease in large carnivores. The goal of this study was to determine the habitat selection of cheetahs ( Acinonyx jubatus ) in a human-wildlife landscape at multiple spatial scales. Cheetahs are a wide-ranging, large carnivore, whose significant decline is largely attributed to habitat loss and fragmentation. It is believed that 77% of the global cheetah population ranges outside protected areas, yet little is known about cheetahs' resource use in areas where they co-occur with people. The selection, or avoidance, of three anthropogenic variables (human footprint density, distance to main roads and wildlife areas) and five environmental variables (open habitat, semiclosed habitat, edge density, patch density and slope), at multiple spatial scales, was determined by analyzing collar data from six cheetahs. Cheetahs selected variables at different scales; anthropogenic variables were selected at broader scales (720-1440 m) than environmental variables (90-180 m), suggesting that anthropogenic pressures affect habitat selection at a home-range level, whilst environmental variables influence site-level habitat selection. Cheetah presence was best explained by human presence, wildlife areas, semiclosed habitat, edge density and slope. Cheetahs showed avoidance for humans and steep slopes and selected for wildlife areas and areas with high proportions of semiclosed habitat and edge density. Understanding a species' resource requirements, and how these might be affected by humans, is crucial for conservation. Using a multiscale approach, we provide new insights into the habitat selection of a large carnivore living in a human-wildlife landscape.
- Published
- 2018
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28. Natural and anthropogenic drivers of cub recruitment in a large carnivore.
- Author
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Broekhuis F
- Abstract
Recruitment is a critical parameter governing population dynamics and influences population persistence. Understanding the drivers of recruitment is therefore important for conservation, especially for long-lived mammals such as large carnivores, which have low reproductive rates, rendering them prone to extinction. Using cheetahs ( Acinonyx jubatus ) as a model species, I investigated the variation in cub recruitment in relation to habitat and the abundance of tourists and predators. Per litter, female cheetahs on average raised 1.71 ± 1.35 cubs to independence, but this varied depending on the presence of open habitat and the abundance of tourists, both of which had a negative effect on cub recruitment. More specifically, female cheetahs that were mostly found in open habitats on average raised 1.69 ± 0.14 cubs per litter to independence compared to 3.04 ± 0.26 cubs in denser habitat. Similarly, female cheetahs that were exposed to high tourist abundance on average raised 0.21 ± 0.72 cubs to independence compared to 2.32 ± 0.11 cubs in low tourism areas. Neither lion nor spotted hyaena abundance had an impact on the number of cubs that were recruited. Based on these findings, I recommend that the importance of a heterogeneous environment should be taken into consideration in habitat management, restoration efforts, and reintroduction programs. In addition, tourist quotas should be put in place in high visitation areas and strict wildlife viewing guidelines, such as number of vehicles, tourist behavior, time spent, and distance to a sighting, should be enforced. Cub recruitment is an important component of species persistence and incorporating these findings could aid conservation efforts for species that are increasingly under threat.
- Published
- 2018
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29. Identification of human-carnivore conflict hotspots to prioritize mitigation efforts.
- Author
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Broekhuis F, Cushman SA, and Elliot NB
- Abstract
Human-carnivore conflict is a primary driver of carnivore declines worldwide and resolving these conflicts is a conservation priority. However, resources to mitigate conflicts are limited and should be focused on areas of highest priority. We conducted 820 semistructured interviews with community members living within Kenya's Maasai Mara ecosystem. A multiscale analysis was used to determine the influence of husbandry and environmental factors on livestock depredation inside livestock enclosures (bomas). Areas with a high proportion of closed habitat and protected areas had the highest risk of depredation. Depredation was most likely to occur at weak bomas and at households where there were fewer dogs. We used the results to identify potential conflict hotspots by mapping the probability of livestock depredation across the landscape. 21.4% of the landscape was classified as high risk, and within these areas, 53.4% of the households that were interviewed had weak bomas. Synthesis and applications . With limited resources available to mitigate human-carnivore conflicts, it is imperative that areas are identified where livestock is most at risk of depredation. Focusing mitigation measures on high-risk areas may reduce conflict and lead to a decrease in retaliatory killings of predators.
- Published
- 2017
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30. The global decline of cheetah Acinonyx jubatus and what it means for conservation.
- Author
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Durant SM, Mitchell N, Groom R, Pettorelli N, Ipavec A, Jacobson AP, Woodroffe R, Böhm M, Hunter LT, Becker MS, Broekhuis F, Bashir S, Andresen L, Aschenborn O, Beddiaf M, Belbachir F, Belbachir-Bazi A, Berbash A, Brandao de Matos Machado I, Breitenmoser C, Chege M, Cilliers D, Davies-Mostert H, Dickman AJ, Ezekiel F, Farhadinia MS, Funston P, Henschel P, Horgan J, de Iongh HH, Jowkar H, Klein R, Lindsey PA, Marker L, Marnewick K, Melzheimer J, Merkle J, M'soka J, Msuha M, O'Neill H, Parker M, Purchase G, Sahailou S, Saidu Y, Samna A, Schmidt-Küntzel A, Selebatso E, Sogbohossou EA, Soultan A, Stone E, van der Meer E, van Vuuren R, Wykstra M, and Young-Overton K
- Subjects
- Africa, Animals, Asia, Biodiversity, Computer Simulation, Extinction, Biological, Models, Biological, Population Dynamics trends, Risk Factors, Acinonyx, Conservation of Natural Resources
- Abstract
Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes., Competing Interests: The authors declare no conflict of interest.
- Published
- 2017
- Full Text
- View/download PDF
31. Serosurvey for Selected Viral Pathogens among Sympatric Species of the African Large Predator Guild in Northern Botswana.
- Author
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Chaber AL, Cozzi G, Broekhuis F, Hartley R, and W McNutt J
- Subjects
- Animals, Botswana, Distemper Virus, Canine, Lentiviruses, Feline, Sympatry, Antibodies, Viral analysis, Hyaenidae virology, Lions virology
- Abstract
The recent increase in the creation of transboundary protected areas and wildlife corridors between them lends importance to information on pathogen prevalence and transmission among wildlife species that will become connected. One such initiative is the Kavango Zambezi Transfrontier Conservation Area of which Botswana's Okavango Delta constitutes a major contribution for wildlife and ecosystems. Between 2008 and 2011, we collected serum samples from 14 lions ( Panthera leo ), four leopards ( Panthera pardus ), 19 spotted hyenas ( Crocuta crocuta ), and six cheetahs ( Acinonyx jubatus ) in the Okavango. Samples were tested for antibodies against canine distemper virus (CDV), feline panleukopenia virus, enteric coronavirus, feline calicivirus, feline herpesvirus (FHV-1), and feline immunodeficiency virus (FIV). Evidence of exposure to all of these pathogens was found, to varying degrees, in at least one of the species sampled. High antibody prevalence (>90%) was only found to FHV-1 and FIV in lions. Only hyenas (26%, 5/19) were positive for CDV antibody. Except for one case, all individuals displayed physical conditions consistent with normal health for ≥12 mo following sampling. Our results emphasize the need for a comprehensive, multispecies approach to disease monitoring and the development of coordinated management strategies for subpopulations likely to be connected in transboundary initiatives.
- Published
- 2017
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32. Counting Cats: Spatially Explicit Population Estimates of Cheetah (Acinonyx jubatus) Using Unstructured Sampling Data.
- Author
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Broekhuis F and Gopalaswamy AM
- Subjects
- Animals, Bayes Theorem, Female, Kenya, Male, Population Density, Acinonyx, Models, Theoretical
- Abstract
Many ecological theories and species conservation programmes rely on accurate estimates of population density. Accurate density estimation, especially for species facing rapid declines, requires the application of rigorous field and analytical methods. However, obtaining accurate density estimates of carnivores can be challenging as carnivores naturally exist at relatively low densities and are often elusive and wide-ranging. In this study, we employ an unstructured spatial sampling field design along with a Bayesian sex-specific spatially explicit capture-recapture (SECR) analysis, to provide the first rigorous population density estimates of cheetahs (Acinonyx jubatus) in the Maasai Mara, Kenya. We estimate adult cheetah density to be between 1.28 ± 0.315 and 1.34 ± 0.337 individuals/100km2 across four candidate models specified in our analysis. Our spatially explicit approach revealed 'hotspots' of cheetah density, highlighting that cheetah are distributed heterogeneously across the landscape. The SECR models incorporated a movement range parameter which indicated that male cheetah moved four times as much as females, possibly because female movement was restricted by their reproductive status and/or the spatial distribution of prey. We show that SECR can be used for spatially unstructured data to successfully characterise the spatial distribution of a low density species and also estimate population density when sample size is small. Our sampling and modelling framework will help determine spatial and temporal variation in cheetah densities, providing a foundation for their conservation and management. Based on our results we encourage other researchers to adopt a similar approach in estimating densities of individually recognisable species.
- Published
- 2016
- Full Text
- View/download PDF
33. Risk avoidance in sympatric large carnivores: reactive or predictive?
- Author
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Broekhuis F, Cozzi G, Valeix M, McNutt JW, and Macdonald DW
- Subjects
- Acinonyx physiology, Animal Distribution, Animals, Botswana, Ecosystem, Hyaenidae, Lions, Risk Factors, Behavior, Animal, Competitive Behavior, Predatory Behavior
- Abstract
1. Risks of predation or interference competition are major factors shaping the distribution of species. An animal's response to risk can either be reactive, to an immediate risk, or predictive, based on preceding risk or past experiences. The manner in which animals respond to risk is key in understanding avoidance, and hence coexistence, between interacting species. 2. We investigated whether cheetahs (Acinonyx jubatus), known to be affected by predation and competition by lions (Panthera leo) and spotted hyaenas (Crocuta crocuta), respond reactively or predictively to the risks posed by these larger carnivores. 3. We used simultaneous spatial data from Global Positioning System (GPS) radiocollars deployed on all known social groups of cheetahs, lions and spotted hyaenas within a 2700 km(2) study area on the periphery of the Okavango Delta in northern Botswana. The response to risk of encountering lions and spotted hyaenas was explored on three levels: short-term or immediate risk, calculated as the distance to the nearest (contemporaneous) lion or spotted hyaena, long-term risk, calculated as the likelihood of encountering lions and spotted hyaenas based on their cumulative distributions over a 6-month period and habitat-associated risk, quantified by the habitat used by each of the three species. 4. We showed that space and habitat use by cheetahs was similar to that of lions and, to a lesser extent, spotted hyaenas. However, cheetahs avoided immediate risks by positioning themselves further from lions and spotted hyaenas than predicted by a random distribution. 5. Our results suggest that cheetah spatial distribution is a hierarchical process, first driven by resource acquisition and thereafter fine-tuned by predator avoidance; thus suggesting a reactive, rather than a predictive, response to risk., (© 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.)
- Published
- 2013
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34. Comparison of the effects of artificial and natural barriers on large African carnivores: implications for interspecific relationships and connectivity.
- Author
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Cozzi G, Broekhuis F, McNutt JW, and Schmid B
- Subjects
- Animals, Botswana, Ecosystem, Geographic Information Systems, Spatial Analysis, Species Specificity, Animal Distribution, Carnivora physiology, Conservation of Natural Resources, Predatory Behavior
- Abstract
1. Physical barriers contribute to habitat fragmentation, influence species distribution and ranging behaviour, and impact long-term population viability. Barrier permeability varies among species and can potentially impact the competitive balance within animal communities by differentially affecting co-occurring species. The influence of barriers on the spatial distribution of species within whole communities has nonetheless received little attention. 2. During a 4-year period, we studied the influence of a fence and rivers, two landscape features that potentially act as barriers on space use and ranging behaviour of lions Panthera leo, spotted hyenas Crocuta crocuta, African wild dogs Lycaon pictus and cheetahs Acinonyx jubatus in Northern Botswana. We compared the tendencies of these species to cross the barriers using data generated from GPS-radio collars fitted to a total of 35 individuals. Barrier permeability was inferred by calculating the number of times animals crossed a barrier vs. the number of times they did not cross. Finally, based on our results, we produced a map of connectivity for the broader landscape system. 3. Permeability varied significantly between fence and rivers and among species. The fence represented an obstacle for lions (permeability = 7.2%), while it was considerably more permeable for hyenas (35.6%) and wild dogs and cheetahs (≥ 50%). In contrast, the rivers and associated floodplains were relatively permeable to lions (14.4%) while they represented a nearly impassable obstacle for the other species (<2%). 4. The aversion of lions to cross the fence resulted in a relatively lion-free habitat patch on one side of the fence, which might provide a potential refuge for other species. For instance, the competitively inferior wild dogs used this refuge significantly more intensively than the side of the fence with a high presence of lions. 5. We showed that the influence of a barrier on the distribution of animals could potentially result in a broad-scale modification of community structure and ecology within a guild of co-occurring species. As habitat fragmentation increases, understanding the impact of barriers on species distributions is thus essential for the implementation of landscape-scale management strategies, the development and maintenance of corridors and the enhancement of connectivity., (© 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.)
- Published
- 2013
- Full Text
- View/download PDF
35. Fear of the dark or dinner by moonlight? Reduced temporal partitioning among Africa's large carnivores.
- Author
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Cozzi G, Broekhuis F, McNutt JW, Turnbull LA, Macdonald DW, and Schmid B
- Subjects
- Africa, Animals, Time Factors, Carnivora physiology, Circadian Rhythm, Predatory Behavior physiology
- Abstract
Africa is home to the last intact guild of large carnivores and thus provides the only opportunity to investigate mechanisms of coexistence among large predator species. Strong asymmetric dominance hierarchies typically characterize guilds of large carnivores; but despite this asymmetry, subdominant species may persist alongside their stronger counterparts through temporal partitioning of habitat and resources. In the African guild, the subdominant African wild dogs and cheetahs are routinely described as diurnal and crepuscular. These activity patterns have been interpreted to result from the need to avoid encounters with the stronger, nocturnal spotted hyenas and lions. However, the idea that diel activity patterns of carnivore species are strongly shaped by competition and predation has recently been challenged by new observations. In a three-year study in the Okavango Delta, we investigated daily activity patterns and temporal partitioning for wild dogs, cheetahs, spotted hyenas and lions by fitting radio collars that continuously recorded activity bursts, to a total of 25 individuals. Analysis of activity patterns throughout the 24-h cycle revealed an unexpectedly high degree of temporal overlap among the four species. This was mainly due to the extensive and previously undescribed nocturnal activity of wild dogs and cheetahs. Their nocturnal activity fluctuated with the lunar cycle, represented up to 40% of the diel activity budget and was primarily constrained by moonlight availability. In contrast, the nocturnal activity patterns of lions and hyenas were unaffected by moonlight and remained constant over the lunar cycle. Our results suggest that other ecological factors such as optimal hunting conditions have shaped the diel activity patterns of subdominant, large predators. We suggest that they are "starvation driven" and must exploit every opportunity to obtain a meal. The benefits of activity on moonlit nights therefore offset the risks of encountering night-active predators and competitors.
- Published
- 2012
- Full Text
- View/download PDF
36. Movement activity based classification of animal behaviour with an application to data from cheetah (Acinonyx jubatus).
- Author
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Grünewälder S, Broekhuis F, Macdonald DW, Wilson AM, McNutt JW, Shawe-Taylor J, and Hailes S
- Subjects
- Animals, Feeding Behavior physiology, Female, Male, Seasons, Support Vector Machine, Acinonyx physiology, Behavior, Animal physiology, Movement physiology
- Abstract
We propose a new method, based on machine learning techniques, for the analysis of a combination of continuous data from dataloggers and a sampling of contemporaneous behaviour observations. This data combination provides an opportunity for biologists to study behaviour at a previously unknown level of detail and accuracy; however, continuously recorded data are of little use unless the resulting large volumes of raw data can be reliably translated into actual behaviour. We address this problem by applying a Support Vector Machine and a Hidden-Markov Model that allows us to classify an animal's behaviour using a small set of field observations to calibrate continuously recorded activity data. Such classified data can be applied quantitatively to the behaviour of animals over extended periods and at times during which observation is difficult or impossible. We demonstrate the usefulness of the method by applying it to data from six cheetah (Acinonyx jubatus) in the Okavango Delta, Botswana. Cumulative activity data scores were recorded every five minutes by accelerometers embedded in GPS radio-collars for around one year on average. Direct behaviour sampling of each of the six cheetah were collected in the field for comparatively short periods. Using this approach we are able to classify each five minute activity score into a set of three key behaviour (feeding, mobile and stationary), creating a continuous behavioural sequence for the entire period for which the collars were deployed. Evaluation of our classifier with cross-validation shows the accuracy to be 83%-94%, but that the accuracy for individual classes is reduced with decreasing sample size of direct observations. We demonstrate how these processed data can be used to study behaviour identifying seasonal and gender differences in daily activity and feeding times. Results given here are unlike any that could be obtained using traditional approaches in both accuracy and detail.
- Published
- 2012
- Full Text
- View/download PDF
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