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The conservation of pollinators, such as bees, is important because they provide criticalpollination services in urban, natural, and agricultural ecosystems. While pollinators and theirservices are better studied in agricultural systems, less is known about the pollinators and theirfloral visitation patterns in urban/suburban areas. This includes the knowledge of bee speciespresent on the University of California, Riverside campus, located in an urban setting. Urbanareas, including college campuses, have been known to provide floral resources to pollinatorswith the integration of urban greenspaces. In this study, we aimed to: (1) characterize pollinatorvisitation to landscaping plantings on the University of California, Riverside campus, and (2)describe their foraging behaviors. Six plots throughout the campus were selected, with mostmeasuring at least 1 ha and each at least 100 meters apart. In these plots, we observed andrecorded any pollinators visiting floral species. We used mark-recapture methods to assesswhether the bee species stayed loyal to a specific floral species or whether they visited a widevariety of plants. Overall, we detected a total of 12 pollinator species marked that had visited 36flowering plant species in our plots in the UC Riverside campus. Of these 12 pollinator species,three were recaptured, Bombus melanopygus, Melissodes spp., and Apis mellifera. Recaptureprobability varied by the plant species visited and the pollinator’s identity but was consistentacross plots. Overall, our findings suggest that floral resources provided in urban greenspaces atthe University of California, Riverside have the potential to support native pollinatorcommunities.

Photo identification involves classifying unique features of a specific individual. The distinguishing feature used in most sea turtle photo ID studies are the scale patterns on the head. Yet the scale patterns on the turtles' flippers are arguably more complex and could provide an alternative and more robust area for photo ID. Here, we compared the accuracy of the Automatic Photo Identification Suite (APHIS) software to identify individual juvenile and subadult green turtles (Chelonia mydas) based on scale patterns on either the head or the flippers. Photographs were taken using standardized guidelines and then analyzed via APHIS after manually placing marks at intersection points between all scales around a predefined area. We tested whether using 6, 10, or 14 scales influenced accuracy of identifications, and determined that incorporating 14 scales provided the most correct identifications (1st rank) for both head and flipper photo ID. After determining the most accurate location for identification for the head and flippers (dorsal view of the head and digits of the fore-flipper), we conclude that photo ID using flipper scales in APHIS can identify individuals with higher accuracy (100%) than head scales (86%). Nevertheless, as turtles may contort the shape of their flippers during natural movements while the surface of the head remains rigid, photo ID for flippers may currently only be suitable when the flipper can be maintained in a flat position

Malaise traps are extensively used in insect surveys and studies, yet the detectability of insects in relation to the traps remain unknown. Detectability is the odds that a taxon ends up in a trap, given that the taxon is present in the area around the trap. The detectability of a taxon depends on three main factors – Population size of the taxa, its activity, and its movement patterns. In this study, I aimed to find how weather influence the activity and thus detectability of insects in Malaise traps, and to develop a marking technique for surveying insect movement patterns around the traps. To achieve my aim of developing a novel marking technique, I tested the effect of fluorescent dusts on survival and flight ability of insects, concluding that the dusts showed no overall negative effects. I then developed a passive marking device of insects in Malaise traps, using the fluorescent dusts as marking mediums. I re-released marked individuals in a forest habitat, inside a network of Malaise traps, and emptied the traps each day. The recapture rates of marked individuals were 4.5% and the technique deemed an effective method for passively marking insects. Furthermore, to understand how weather influences activity and subsequent detectability, I conducted High-Resolution Sampling. I emptied 24 Malaise traps every second hour for five days, recording temperature, cloud cover, wind speed and relative humidity at each sampling event. This data was used to investigate how these variables affect insect activity, and in what directions. Increased temperature increased abundances of insects. Increased wind speed and cloud cover lowered abundances. Relative humidity had no effect on abundances. Furthermore, high wind speeds, and to some extent temperatures, subset the sampled community by favouring insects with smaller wing area than expected by the normal wing-to-body ratio. However, the effect of each environmental factor was small. In conclusion, this study shows that Mala

Obtaining survival estimates on the Interior population of band-tailed pigeons (Patagioenas fasciata) is challenging because they are trap shy, but the joint use of passive integrated transponder (PIT) tags and bands is a potential solution. We investigated the use of PIT tags to passively recapture band‐tailed pigeon at 3 locations in New Mexico, USA, to estimate survival. From 2013–2015, we captured, banded, and marked >600 individual band‐tailed pigeons with PIT tags. To estimate annual survival rates, we used a Barker multi‐state joint live and dead encounters and resighting model. Survival models excluding transience had survival estimates across site, sex, and year of 0.86 (95% CI = 0.84–0.88) for after hatch year birds and 0.63 (95% CI = 0.48–0.76) for hatch year birds. These results are consistent with other survival estimates reported for the Interior population of band‐tailed pigeons using band return data and potentially provide an effective alternative method of monitoring survival of this population.

Sustainable management of fish stocks requires knowledge of stock structure and connectivity between spawning and feeding habitats. Cod in the Sound in the western Baltic Sea are an example of a stock component with complex connectivity patterns. Currently cod in this area are managed as part of the western Baltic cod stock, while several studies suggest potential connectivity with the neighbouring stock in Kattegat. Here we assess the degree of ecological connectivity of cod in the Sound with the neighbouring areas using historical tagging data from 1957 to 1987, and contemporary growth data from trawl surveys collected between 2007 and 2021. Furthermore, data from cod tagged outside of the Sound between 1960 and 2018 and recaptured in the Sound was used to examine immigration from outside areas. The ecological connectivity between the Sound and Kattegat appeared to be considerable, primarily during the spawning season. Furthermore, cod tagged in the northern Sound were most likely to be recaptured in Kattegat while cod tagged in the southern part of the Sound were mainly recaptured in the Sound. Only 40 out of 16,789 tagged cod released outside of the Sound were eventually recaptured inside the Sound. Overall, these results highlight the need for further examination into the current stock structure of cod in the western Baltic and adjacent areas.

Grassland birds are among the fastest declining avian species in North America, primarily due to habitat loss. In the southeastern United States, much grassland and open savanna habitat has been converted to timber production or agriculture, neither of which typically provides habitat for breeding or wintering grassland birds. Powerline right-of-ways could provide suitable habitat for many grassland species because these areas are maintained to be treeless. We studied the population dynamics of Henslow's Sparrows (Centronyx henslowii) wintering in powerline right-of-ways in southeastern Georgia through an 11-year mark-recapture study. We used a robust design Cormack-Jolly-Seber model to estimate probability of detection and apparent survival. Abundance varied substantially among years at each site, with density varying from 1.7 to 8.5 birds/ha. Within-year detection probability was moderately high at 28% (24-33%, 95% credible interval [CI]), but apparent survival was very low at 13% (9-17%, 95% CI). This low apparent survival was likely due to low return rates (and not necessarily low survival). However, birds that did return to the study sites had extremely high site fidelity, with 82% of across-year recaptures < 200 m apart. This apparent incongruity between low apparent survival rates (likely due to emigration from the study sites) and high site fidelity for returning individuals could be explained by the dependability of the rightof-way habitat, which differs from typically patchy and temporally variable grassland and savanna wintering habitats. Dependable habitat may allow for higher site fidelity than this species would otherwise have, potentially resulting in the high densities we observed. Thousands of miles of right-of-ways in Georgia, and other southeastern states, could be managed to maximize potential habitat for declining grassland bird species.

The impact of climate change on reptile populations is poorly studied, and this includes snakes, which are elusive by nature, making it problematic to preform long-term population studies. Here we have done both. With the help of over 60 years of mark-recapture data, 1942-2009 and 2021-2022, on a population of grass snakes (Natrix natrix), the goal was to assess the implications of climate change on the population dynamics. The results found that adult survival was higher during the winter compared to the summer, especially for smaller individuals. Winter survival was positively influenced by increased winter precipitation, which is probably correlated with a greater snow cover. However, winter survival has decreased over time in line with climate change. The opposite was observed in summer survival, which has increased over time. Summer survival increased with the size of the snake, and along with this increasing winter and summer temperatures, associated with longer active periods, seem to have increased the body size of the snakes, especially the males. Males and females have increased in size with 5 and 9 cm, respectively, over a 60 years period. Survival was also higher in males compared to a same sized female. Probably as a result of different predation pressure and/or higher survival cost of reproduction for the females. We also observed a decrease of the male ratio in the population over the years. In line with a changed climate, the influence of season on survival, changes with increasing survival during the summers, and the opposite during the winter. But since the population seem to have been stable over time, the negative effects of increased winter mortality could have been balanced by the increased summer survival. As for now, there are no visible complications on the snake population due to climate change. But since the winters are expected to become more unstable which results in more extreme weathers, and as the survival is affected by factors assoc

Grassland birds are among the fastest declining avian species in North America, primarily due to habitat loss. In the southeastern United States, much grassland and open savanna habitat has been converted to timber production or agriculture, neither of which typically provides habitat for breeding or wintering grassland birds. Powerline right-of-ways could provide suitable habitat for many grassland species because these areas are maintained to be treeless. We studied the population dynamics of Henslow's Sparrows (Centronyx henslowii) wintering in powerline right-of-ways in southeastern Georgia through an 11-year mark-recapture study. We used a robust design Cormack-Jolly-Seber model to estimate probability of detection and apparent survival. Abundance varied substantially among years at each site, with density varying from 1.7 to 8.5 birds/ha. Within-year detection probability was moderately high at 28% (24-33%, 95% credible interval [CI]), but apparent survival was very low at 13% (9-17%, 95% CI). This low apparent survival was likely due to low return rates (and not necessarily low survival). However, birds that did return to the study sites had extremely high site fidelity, with 82% of across-year recaptures < 200 m apart. This apparent incongruity between low apparent survival rates (likely due to emigration from the study sites) and high site fidelity for returning individuals could be explained by the dependability of the rightof-way habitat, which differs from typically patchy and temporally variable grassland and savanna wintering habitats. Dependable habitat may allow for higher site fidelity than this species would otherwise have, potentially resulting in the high densities we observed. Thousands of miles of right-of-ways in Georgia, and other southeastern states, could be managed to maximize potential habitat for declining grassland bird species.

[Context] Robust assessment of functional connectivity in amphibian population networks is essential to address their global decline. The potential of graph theory to characterize connectivity among amphibian populations has already been confirmed, but the movement data on which modelled graphs rely are often scarce and inaccurate. While probabilistic methods that account for intraspecific variability in dispersal better reflect the biological reality of functional connectivity, they must be informed by systematically recorded individual movement data, which are difficult to obtain for secretive taxa like amphibians., [Objectives] Our aim is to assess the applied potential of probabilistic graph theory to characterize overall connectivity across amphibian pondscapes using finescale capture-recapture data, and to inform conservation management based on the role of ponds on functional connectivity., [Methods] We monitored an amphibian community in a pondscape located in a Spanish “dehesa” for 2 years. Photoidentification was used to build capture histories for individuals of six species, from which dispersal kernels and population sizes were estimated to model probabilistic graphs., [Results] We obtained kernels of variable robustness for six species. Node importance for connectivity varied between species, but with common patterns such as shared road crossing areas and the presence of coincident interconnected pond clusters., [Conclusions] The combination of photoidentification, capture-recapture data and graph theory allowed us to characterize functional connectivity across the pondscape of study accounting for dispersal variability and identify areas where conservation actions could be most efficient. Our results highlight the need to account for interspecific differences in the study and management of amphibian pondscapes.

Barriers in the estuaries of the rivers prevent the immigration of glass eels (Anguilla anguilla) arriving on the European coast every spring. This leads to an unnatural accumulation of migrating glass eels below the barriers, and this may lead to additional losses in glass eels by piscivorous fish. The proportion of predation losses can be estimated using mark-recapture techniques and abundance estimates in combination with stomach content analysis of piscivorous fish. Nonetheless, whether tagging transparent glass eels increases predation risk and what the digestion rate of glass eel is in piscivorous fish are unknown. This study aimed to determine whether there is an increased predation risk for tagged glass eel; it also studies glass eel digestion status in piscivorous fish after appointed time frames. A laboratory experiment with 48 trials was conducted. Tagged (visible implanted elastomer, VIE) and untagged glass eels were exposed to small (19.1–24.4 cm) and large (31.9–43.5 cm) sea bass (Dicentrarchus labrax) during a 2 h trial. In 48% of the trials, successful predation was present and 13% showed clear predation attempts in which bass did not capture glass eels. No significant difference was found in predation rate between tagged and untagged glass eels and between red and blue tagged glass eels. Large sea bass predated more, but all sizes consumed glass eel under laboratory conditions. Stomach content analysis showed intact glass eel bodies 4–6 h after ending the 2 h trial and parts of glass eel bodies up to 16–18 h. This study showed that tagging does not increase predation in mark-recapture studies using VIE-tags in transparent glass eel. It also shows that the proportion of predation in relation to local glass eel abundance can be estimated if stomach content analysis is conducted within 4–6 h after predation.

The diamondback terrapin (Malaclemys terrapin) is a charismatic and long-lived species of the United States eastern coast, and the only North American turtle that exclusively inhabits coastal brackish waters. Many terrapin populations are declining, and these declines have been largely linked to human activities; however, few studies have documented human and natural factors affecting terrapin population demography. Jamaica Bay, an urban estuary located in southern New York City, USA, is home to 2 nesting aggregations of terrapins, located at Ruler's Bar Hassock (RBH) and John F. Kennedy Airport (JFK). We analyzed mark-recapture data for RBH from 2003–2018 and JFK from 2011–2018 to estimate annual survivorship of female diamondback terrapins and test the effects of 3 factors (a hurricane, water quality represented by nitrogen concentration, and injuries) on survival. The initial estimated annual survival was high (0.93) at RBH but declined to 0.89, while survival remained constant at JFK (0.92). Models examining the effect of Hurricane Sandy (2012) indicated a significant decline in survival in the 2 years following the hurricane in the RBH nesting aggregation but no change at JFK. Water quality did not influence trends in either aggregation, but the presence of major injuries (caused by boat collisions, predators, and the hurricane) significantly reduced annual survival at RBH. We propose increasing terrapin survivorship through mitigation of boat traffic, reducing populations of northern raccoons (Procyon lotor) to reduce injury to female terrapins and decrease egg and hatchling mortality, and increased law enforcement to reduce on-going poaching and capture as illegal by-catch.

Understanding patterns of dispersal behaviour of threatened species is important in conservation biology and population ecology, especially in fragmented landscapes. Dupont’s Lark Chersophilus duponti is a threatened passerine whose European population has declined by around 40% in the last decade. To study natal and breeding dispersal of the species, we used a long-term mark-recapture dataset (2011–2019) and analysed the records of 32 males (39 dispersal movements) and five females (five dispersal movements) captured during the breeding season at Rincón de Ademuz (Valencia, eastern Spain). Adult birds had a median breeding dispersal of 154 m (Q25-Q75 = 70.0–300.3). Among these captures, two adult males dispersed to a new patch of habitat separated by more than 5,800 m. Only one out of 26 nestlings ringed was trapped as an adult bird, which occurred at a site different from the natal territory (4,500 m). Our results show a low breeding dispersal for the species and are, in essence, in agreement with previous studies carried out in the Ebro Valley metapopulation, one of the core areas for the species in Europe. Nonetheless, unlike in the Ebro Valley, we detected movements of adult birds between habitat patches. The low recovery rate of young birds suggests that they left their natal sites and moved outside the study area or that their survival rate was very low. Future studies focused on the post-fledging survival rate and natal dispersal movements are essential to determine effective conservation measures for the species. Habitat management actions in occupied and potential sites should be carried out close to the areas inhabited by the species to increase the success rate of the interventions and the effective dispersal and therefore population connectivity.

Photo-identification is a non-invasive option for mark-recapture. Here, we tested the effectiveness of APHIS, a semi-automated photo-identification software, to distinguish between individual Bahamian Racers (Cubophis vudii vudii) on the island of Eleuthera, The Bahamas. Over 10 months, we photographed 50 Bahamian Racers. We first identified individuals by manually comparing colouration and scale patterns in the pileus and labial regions. Next, we used APHIS to identify recaptured individuals after manually identifying the locations of intersections of the scales in the pileus and labial regions. In addition, we assessed whether images taken with a hand-held camera or by a smart phone affected the accuracy of APHIS. All recaptured snakes were correctly identified using APHIS from both camera or phone images as validated by our manually derived results. We conclude that APHIS is an effective tool for photo-identification in snakes.

Understanding patterns of dispersal behaviour of threatened species is important in conservation biology and population ecology, especially in fragmented landscapes. Dupont’s Lark Chersophilus duponti is a threatened passerine whose European population has declined by around 40% in the last decade. To study natal and breeding dispersal of the species, we used a long-term mark-recapture dataset (2011–2019) and analysed the records of 32 males (39 dispersal movements) and five females (five dispersal movements) captured during the breeding season at Rincón de Ademuz (Valencia, eastern Spain). Adult birds had a median breeding dispersal of 154 m (Q25-Q75 = 70.0–300.3). Among these captures, two adult males dispersed to a new patch of habitat separated by more than 5,800 m. Only one out of 26 nestlings ringed was trapped as an adult bird, which occurred at a site different from the natal territory (4,500 m). Our results show a low breeding dispersal for the species and are, in essence, in agreement with previous studies carried out in the Ebro Valley metapopulation, one of the core areas for the species in Europe. Nonetheless, unlike in the Ebro Valley, we detected movements of adult birds between habitat patches. The low recovery rate of young birds suggests that they left their natal sites and moved outside the study area or that their survival rate was very low. Future studies focused on the post-fledging survival rate and natal dispersal movements are essential to determine effective conservation measures for the species. Habitat management actions in occupied and potential sites should be carried out close to the areas inhabited by the species to increase the success rate of the interventions and the effective dispersal and therefore population connectivity.

Anadromous sub-populations of stenohaline freshwater fish are vastly understudied in the estuarine environment. The purpose of the present study was therefore to study the population ecology, growth rate, and physico-chemical environment of an anadromous sub-population of European perch (Perca fluviatilis) from the western Baltic Sea. Fish (301) were marked with external identification tags, and anglers and fishermen reported recaptures in a citizen science set-up over three years. In addition, scale samples were collected for population growth rate determination. Furthermore, water temperature, salinity, and oxygen concentration were monitored in the area. The fish showed a consistent annual migration pattern over the three years residing in a bay during summer while being in a delta during autumn, winter, and spring. The population had a high growth rate, but a meta-analysis showed that growth of European perch is not distinctly different between estuarine and freshwater populations. The average salinity measured in the area was around 10, but increased on multiple occasions to salinity levels known for being physiologically challenging for European perch. We argue that high growth rates of estuarine European perch is more likely due to high food availability and low interspecific competition in this environment, rather than due to physiologically optimal salinities. Furthermore, the European perch in the present study lived on the edge of the species salinity tolerance, and the migration into the delta during winter is likely a combination of avoiding high salinities at low temperatures and a spawning migration. These results are important knowledge for the management of estuaries and coastal areas, especially as climate change is locally altering these environments drastically, and calls for further studies on other anadromous sub-populations of stenohaline freshwater fish.

鳥取市鳥取砂丘オアシス周辺に営巣するエリザハンミョウの集団の保全に向けて2015年から本種の成虫が発生する夏季に標識再捕法により当地での成虫の発生個体数を調査している。2017年の夏には個体数が激減したため，営巣地を踏圧から守るため鳥取砂丘事務所と環境庁は2018年4月に生息地の周囲をロープで囲った。2018年7月も同様の調査をおこなったがエリザハンミョウの成虫の個体数推定値は最も多かった調査日（7月18日）ですらわずか36と2017年の153個体をさらに大きく下回った。当地では2018年7月5日から3日間連続の大雨で営巣地は水浸しになり，下流側は長期間冠水した。出現個体数の激減の最大の理由はこの冠水であったのかもしれない。 / As a consecutive series of surveys of the population size of a tiger beetle species, Cylinderaelisae (Motschulsky, 1859) at a site nearby so-called “Oasis” in the Tottori Sand Dunes, Tottori City, startedin 2015 (Tsurusaki et al. 2016, 2017, 2018), we estimated population size of the same population of thesame species also in 2018 by using a mark-recapture method. Only a total of 28 adults of C. elisae wereindividually marked during the summer in 2018 (304, 270, and 112 adults in 2015, 2016, 2017 surveys,respectively). The highest number of adults of C. elisae estimated by the Jolly-Seber method was only 36 recorded on 18 July 2018. Most probable reason for the decrease in the number of adults was floods causedby torrential downpour for three consecutive days from 5 July 2018.

Seasonal environmental conditions shape the behavior and life history of virtually all organisms. Climate change is modifying these seasonal environmental conditions, which threatens to disrupt population dynamics. It is conceivable that climatic changes may be beneficial in one season but result in detrimental conditions in another because life-history strategies vary between these time periods. We analyzed the temporal trends in seasonal survival of yellow-bellied marmots (Marmota flaviventer) and explored the environmental drivers using a 40-y dataset from the Colorado Rocky Mountains (USA). Trends in survival revealed divergent seasonal patterns, which were similar across age-classes. Marmot survival declined during winter but generally increased during summer. Interestingly, different environmental factors appeared to drive survival trends across age-classes. Winter survival was largely driven by conditions during the preceding summer and the effect of continued climate change was likely to be mainly negative, whereas the likely outcome of continued climate change on summer survival was generally positive. This study illustrates that seasonal demographic responses need disentangling to accurately forecast the impacts of climate change on animal population dynamics.

Current abundance estimates for populations of common bottlenose dolphins (Tursiops truncatus, Montagu, 1821) in bays, sounds, and estuaries are lacking throughout most of the northwestern Gulf of Mexico, including areas of Texas and western Louisiana. To address this issue, we conducted 92 small-boat photographic identification surveys covering ~2000 km2 and comprising ~11,000 km of track-line in winter and summer seasons in West Bay, TX (2014 – 2015, n = 25), the Galveston Bay, TX system (2016, n = 50), Sabine Lake, TX (2017, n = 17), and adjacent coastal waters. Individual dolphin encounter histories were constrained by spatiotemporal parameters to approximately represent 1) a “Bay” estimate of individuals limited to the interior of each embayment, and 2) a “Selective” estimate of the number of individuals in each survey area (including nearshore coastal waters), filtered for potential transient dolphins. Using the Selective dataset, estimated dolphins (95% CI) were (winter and summer, respectively) 38 (29 – 47) and 37 (33 – 40) for West Bay, 842 (694 – 990) and 1132 (846 – 1417) for Galveston Bay, and 122 (73 – 170) and 162 (114 – 210) for Sabine Lake. A range of 4-15% of marked individuals in each study area were identified as inter-bay matches. These results provide new insights on the potential spatial range of each population, update previous abundance estimates for West Bay and Galveston Bay, and contribute novel population information for Sabine Lake and adjacent coastal waters of the northwestern Gulf of Mexico.

Seasonally flooded lakes in the northeast region of Brazil are important areas used for breeding and feeding by two species of turtle, Kinosternon scorpioides, the Scorpion Mud turtle, and Trachemys adiutrix, the Brazilian Slider Turtle. Over 6 y, we captured, marked, measured, and determined the sex of 183 K. scorpioides and 518 T. adiutrix. Over the study period as a whole, the sex ratio of K. scorpioides did not deviate significantly from 1:1, whereas there was a significant male bias in T. adiutrix. There was no significant relationship between relative abundance and mean monthly rainfall in either species, although we captured significantly smaller K. scorpioides females and larger T. adiutrix individuals (males and females) in the drier years. Seasonal residence times ranged from 14–90 d in K. scorpioides and 14–110 d in T. adiutrix. Residence time was not related significantly to mean monthly rainfall in either species. In K. scorpioides, the estimated annual female population size ranged from 14 to 78 individuals, while that of the males varied from 16 to 88 individuals, while in T. adiutrix, estimates of the female population size ranged from 71 to 444 individuals, and those of males, from 80 to 515 individuals. These findings indicate that both turtle species maintain resident populations in the study area, but present distinct patterns of annual variation in body size and the sex ratios, which points to distinct ecological requirements that may require differential conservation strategies.

BackgroundStable isotope labeling is a promising method for use in insect mark-capture and dispersal studies. Culicoides biting midges, which transmit several important animal pathogens, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), are small flies that develop in various semi-aquatic habitats. Previous Culicoides dispersal studies have suffered from the limitations of other labeling techniques, and an inability to definitively connect collected adult midges to specific immature development sites.ResultsAdult C. sonorensis were successfully labeled with 13C and 15N stable isotopes as larvae developing in a semi-aquatic mud substrate in the laboratory. High and low-dose isotope treatments for both elements significantly enriched midges above the background isotope levels of unenriched controls. Enrichment had no effect on C. sonorensis survival, though a slight (~ 5 day) delay in emergence was observed, and there was no significant effect of pool size on 13C or 15N enrichment levels.ConclusionsStable isotope labeling is life-long, and does not interfere with natural insect behaviors. Stable isotope enrichment using 13C or 15N shows promise for Culicoides dispersal studies in the field. This method can be used to identify adult dispersal from larval source habitat where a midge developed. It may be possible to detect a single enriched midge in a pool of unenriched individuals, though further testing is needed to confirm the sensitivity of this method.

Mark-recapture methods constitute a set of classical ecological tools that are used to collect information on species dispersal and population size. These methods have advanced knowledge in disparate scientific fields, from conservation biology to pest control. Gathering information on the dispersal of mosquito species, such as Aedes aegypti, has become critical since the recognition of their role as vectors of pathogens. Here, we evaluate a method to mark mosquitoes that exploits the rare alkali metals rubidium (Rb) and caesium (Cs), which have been used previously to mark adult insects through feeding. We revised this method by adding Rb and Cs directly to water in which the immature stages of Ae. aegypti were allowed to develop. We then assessed the effect of Rb- and Cs-enriched water on fitness, survival and bioaccumulation in both adult females and their eggs. Results indicated that Cs had adverse effects on Ae. aegypti, even at low concentrations, whereas Rb at low concentrations had no measured effects on exposed individuals and accumulated at detectable levels in adult females. The method described here relies on passive uptake of Rb during immature stages, which has the benefit of avoiding handling or manipulation of the dispersive adults, which enables purer measurement of movement. Moreover, we demonstrated that Rb was transferred efficiently from the marked females to their eggs. To our knowledge, Rb is the only marker used for mosquitoes that has been shown to transfer vertically from females to eggs. The application of Rb rather than more traditional markers may therefore increase the quality (no impact on released individuals) and quantity (both adults and eggs are marked) of data collected during MR studies. The method we propose here can be used in combination with other markers, such as stable isotopes, in order to maximize the information collected during MR experiments.

Mark-recapture methods constitute a set of classical ecological tools that are used to collect information on species dispersal and population size. These methods have advanced knowledge in disparate scientific fields, from conservation biology to pest control. Gathering information on the dispersal of mosquito species, such as Aedes aegypti, has become critical since the recognition of their role as vectors of pathogens. Here, we evaluate a method to mark mosquitoes that exploits the rare alkali metals rubidium (Rb) and caesium (Cs), which have been used previously to mark adult insects through feeding. We revised this method by adding Rb and Cs directly to water in which the immature stages of Ae. aegypti were allowed to develop. We then assessed the effect of Rb- and Cs-enriched water on fitness, survival and bioaccumulation in both adult females and their eggs. Results indicated that Cs had adverse effects on Ae. aegypti, even at low concentrations, whereas Rb at low concentrations had no measured effects on exposed individuals and accumulated at detectable levels in adult females. The method described here relies on passive uptake of Rb during immature stages, which has the benefit of avoiding handling or manipulation of the dispersive adults, which enables purer measurement of movement. Moreover, we demonstrated that Rb was transferred efficiently from the marked females to their eggs. To our knowledge, Rb is the only marker used for mosquitoes that has been shown to transfer vertically from females to eggs. The application of Rb rather than more traditional markers may therefore increase the quality (no impact on released individuals) and quantity (both adults and eggs are marked) of data collected during MR studies. The method we propose here can be used in combination with other markers, such as stable isotopes, in order to maximize the information collected during MR experiments.

BackgroundStable isotope labeling is a promising method for use in insect mark-capture and dispersal studies. Culicoides biting midges, which transmit several important animal pathogens, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), are small flies that develop in various semi-aquatic habitats. Previous Culicoides dispersal studies have suffered from the limitations of other labeling techniques, and an inability to definitively connect collected adult midges to specific immature development sites.ResultsAdult C. sonorensis were successfully labeled with 13C and 15N stable isotopes as larvae developing in a semi-aquatic mud substrate in the laboratory. High and low-dose isotope treatments for both elements significantly enriched midges above the background isotope levels of unenriched controls. Enrichment had no effect on C. sonorensis survival, though a slight (~ 5 day) delay in emergence was observed, and there was no significant effect of pool size on 13C or 15N enrichment levels.ConclusionsStable isotope labeling is life-long, and does not interfere with natural insect behaviors. Stable isotope enrichment using 13C or 15N shows promise for Culicoides dispersal studies in the field. This method can be used to identify adult dispersal from larval source habitat where a midge developed. It may be possible to detect a single enriched midge in a pool of unenriched individuals, though further testing is needed to confirm the sensitivity of this method.

Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing project of the Eurasian Oystercatcher (Haematopus ostralegus) in the Netherlands. Methods: Our analysis included 8909 colour-ringed oystercatchers with 118,071 resightings, predominantly ringed and observed by citizen scientists. We quantified how ring wear and loss may vary with ring colour and age, and how this may impact resighting probabilities. We then determined how ring loss may impact survival estimates and resighting probabilities of mark-recapture models by simulating four scenarios of how citizen scientists may resight and report birds with lost colour rings. Results: Annual rates of colour ring loss averaged 2.5% compared with 1% for ring wear, but lost rings also had a higher reporting probability (31.2%) than worn rings (10.3%). Lost rings may not directly impact survival estimates since 50% of oystercatchers with lost rings could still be uniquely identified. Ring wear and loss rapidly increased between 10 and 15 years after ringing. Rates of ring loss were comparable amongst ring colours, but the wear rate appeared higher for red and white rings compared to other colours. Rates of ring wear and loss varied significantly amongst different regions in our study, which were characterised as having different habitat features. Differential rates of ring wear may have important implications for studies conducted over large geographical scales or of multiple species. Conclusions: Based on simulations of ring loss in our population, estimates of apparent survival may be 0.3-1.2% lower whilst the impact of ring wear was deemed even lower. We developed a table of recommendations containing advice for ring fitting, data collection, study design, and mark-recapture analyses, so that future colour-ringing studies can benefit from our experiences in collecti

鳥取市鳥取砂丘オアシス周辺に営巣するエリザハンミョウの集団の保全に向けて2015 年から本種の成虫が発生する夏季に標識再捕法により当地での発生個体数を調査している。すでに結果を報告している2016 年までの調査に引き続き2017 年も同様の調査をおこなった。エリザハンミョウの成虫の消長は過去2年よりも早めに進行し，成虫は6月中旬に出現，7月中にはほぼ消失した。この間にマークできた総個体数は112（2015 年は304，2016 年は270）とこの3 年間で最も少なく， Jolly-Seber 法による個体数推定値はもっとも多かった調査日（6 月27 日）でわずか153 であった（2015 年は2,300個体，2016 年は1,460 個体）。この個体数は個体群を健全に維持するために必要とされる最小集団サイズ（MVP）として従来言われてきていた500（個体数変動の大きい動植物では10,000）を大幅に下回っており，危険な状態である。2017 年におけるエリザハンミョウ成虫の早期の出現と消失は2017 年の7 月の高温が，また，個体数の減少にもっとも寄与した要因としては2017 年の4～6 月の少雨が考えられる。 / As a consecutive series of surveys of the population size of a tiger beetle species, Cylindera elisae (Motschulsky 1859) at a site so-called“ Oasis” in the Tottori Sand Dunes, Tottori City, started in 2015 (Tsurusaki et al. 2016, 2017), we estimated population size of the same population of the same species also in 2017 by using a mark-recapture method. A total of 112 adults of C. elisae were individually marked during the summer in 2017 (304 and 270 adults in 2015 and 2016 surveys, respectively). The highest number of adults of C. elisae estimated by the Jolly-Seber method was only 153 recorded on 27 June 2017. This population size is much smaller than 500 which was the number formerly often said as the minimum viable population (MVP), to say nothing of 10,000 as the MVP for univoltine insects whose population size tend to be variable every year. It is probable that high air temperature of July in 2017 brought early emergence and disappearance of C. elisae in 2017. It is also likely that drought at “Oasis” area due to extremely low amount of precipitation from April to June in 2017 was the main factor for the marked decrease of population of this species in 2017. Some measure should be taken for the recovery of this population.

2015年の調査に引き続き，2016年の夏季にも鳥取砂丘オアシス周辺で標識再捕により，当地で絶滅が心配されるエリザハンミョウの生息数を推定した。マークできた個体はエリザハンミョウが270（昨年は304），カワラハンミョウが170（昨年は77），コハンミョウが4（昨年は1：昨年調査の報告書である鶴崎ら2016では「コニワハンミョウ」と誤記）であった。Jolly-Seber法によるエリザハンミョウの個体数推定値はもっとも多かった調査日（6月28日と7月16日）でともに約1,460で，2015年の2,300個体よりも少なかった。おそらく2016年の夏季の高気温のため，成虫の出現期は2015年よりも早く推移し，6 月中旬には成虫が出現し，8月下旬には終息した。エリザハンミョウの幼虫の営巣地はオアシス周辺の尻無川右岸の裸地であるが，成虫は左岸のコウボウシバ群落でも見つかった。カワラハンミョウの成虫は6月下旬から10月上旬まで見られ，170個体をマークしたが再捕獲できた個体は皆無であった。コハンミョウは尻無川の近くで4個体マークしたが本種も再捕獲にいたらなかった。昨年の2個体（マークしたのは1個体）に続けての確認で，細々ではあるが，本種は当地で世代を繰り返している可能性が高い。 / Following a survey of the population size of a tiger beetle species, Cylindera elisae(Motschulsky,1859) in the Tottori Sand Dunes, Tottori City, in 2015 (Tsurusaki et al.2016), we estimated population size of the same population of the same species also in 2016 by using mark-recapture experiments. A total of 270 adults of Cy. elisae , 170 adults of Chaetodera laetescripta (Motschulsky, 1860) and 4 adults of Myriochila speculifera (Chevrolat, 1865) (This species was erroneously recorded as Cicindela transbaicalica japanensis Chaudoir, 1863 in Tsurusaki et al. 2016) were individually marked during the summer in 2016. None of those adults marked were recaptured for the two latter species. The highest number of adults of Cy. elisae estimated by the Jolly-Seber method was ca. 1,460 recorded on both 28 June and 16 July.

鳥取砂丘ではオアシス周辺でしか営巣がみられず個体群の消失が懸念されるエリザハンミョウの成虫に2015年に個体マークをほどこし，標識再捕法により出現個体数を推定した。成虫は6 月下旬から9月下旬までみられた。断続的につづいた長雨の影響などにより8月中旬から1カ月以上のデータが採れなかったが，最盛期と考えられる7月下旬にはJolly-Seber法による個体数推定値は2,300を超えた。この個体数は巣穴調査から予想した生息数よりもかなり多いが，個体数変動の大きい昆虫などで個体群を健全に維持するのに一般に必要とされる約10,000個体には届いていない。交尾は調査開始直後の7月上旬から8月上旬まで継続的にみられた。エリザハンミョウの発見地点と再捕地点はすべてオアシス周辺の湿りをおびた裸地に集中していた。カワラハンミョウが周辺の砂地にまで広く生息するのと対照的である。調査中，コニワハンミョウが2個体，鳥取砂丘オアシス周辺では初めて記録された。Population size of a tiger beetle species, Cylindera elisae (Motschulsky, 1859) whose single colony in the so-called “Oasis” area in Tottori Sand Dunes, Tottori City, Honshu, Japan may be endangered, was estimated in the area in 2015 by using mark-recapture experiments. A total of 304 adults of Cy. elisae and 77 adults of Chaetodera laetescripta (Motschulsky, 1860) were individually marked during the summer, though data from 5 August to 28 September were missing due to a long spells of bad weather and other reasons. The highest number of adults estimated by the Jolly-Seber method was ca. 2,300 recorded on 18 July. Mating pairs were persistently observed from early July to early August. The sites where adults of Cy. elisae were caught first and those where they were recaptured were concentrated on the moistened bare ground near the “Oasis” pool, whereas those of Chaetodera laetescripta (Motschulsky, 1860) were spread out to dry sandy areas neighboring “Oasis”. A few adults of Cicindela transbaicalica japanensis Chaudoir, 1863 were first recorded from “Oasis” area along a stream in the dunes.

While our knowledge of the range of survival that outmigrating juvenile Chinook Salmon experience in different routes of the Sacramento–San Joaquin Delta has increased in recent years, few studies have focused on their survival during outmigration in the Yolo Bypass, the Delta’s primary floodplain. The Yolo Bypass floodplain provides valuable rearing habitat and growth benefits to juvenile fish in flood years, and efforts are underway to improve access to the Yolo Bypass and the Toe Drain, its perennial navigation channel, under a broader range of flows and river stages than is currently possible. We compared variation in transit time, and estimated survival between different release groups of fish outmigrating through the Yolo Bypass or through migratory routes in the lower Sacramento River. Tagged late-fall-run juvenile Chinook Salmon were released in both systems in 2012 and 2013. There was no significant difference between the estimated cumulative probability of survival in the Yolo Bypass system and combined routes of the lower Sacramento River in either year (0.312–0.629 vs. 0.342–0.599, 95% credible interval in 2012; and 0.111–0.408 vs. 0.240–0.407, 95% credible interval in 2013, respectively). The Yolo Bypass had a higher coefficient of variation (CV) in travel time relative to the lower Sacramento River routes in both years (0.34 vs. 0.29 in 2012, and 0.44 vs. 0.34 in 2013). This work suggests that in relatively low water years, the estimated survival of outmigrating juvenile Chinook Salmon in the Toe Drain is directly comparable to routes in the lower Sacramento River, and that metrics of behavioral diversity in movement behavior can and should be incorporated into future telemetry studies.

While our knowledge of the range of survival that outmigrating juvenile Chinook Salmon experience in different routes of the Sacramento–San Joaquin Delta has increased in recent years, few studies have focused on their survival during outmigration in the Yolo Bypass, the Delta’s primary floodplain. The Yolo Bypass floodplain provides valuable rearing habitat and growth benefits to juvenile fish in flood years, and efforts are underway to improve access to the Yolo Bypass and the Toe Drain, its perennial navigation channel, under a broader range of flows and river stages than is currently possible. We compared variation in transit time, and estimated survival between different release groups of fish outmigrating through the Yolo Bypass or through migratory routes in the lower Sacramento River. Tagged late-fall-run juvenile Chinook Salmon were released in both systems in 2012 and 2013. There was no significant difference between the estimated cumulative probability of survival in the Yolo Bypass system and combined routes of the lower Sacramento River in either year (0.312–0.629 vs. 0.342–0.599, 95% credible interval in 2012; and 0.111–0.408 vs. 0.240–0.407, 95% credible interval in 2013, respectively). The Yolo Bypass had a higher coefficient of variation (CV) in travel time relative to the lower Sacramento River routes in both years (0.34 vs. 0.29 in 2012, and 0.44 vs. 0.34 in 2013). This work suggests that in relatively low water years, the estimated survival of outmigrating juvenile Chinook Salmon in the Toe Drain is directly comparable to routes in the lower Sacramento River, and that metrics of behavioral diversity in movement behavior can and should be incorporated into future telemetry studies.

Habitat destruction and fragmentation alter the quality of habitats and put populations under the risk of extinction. Changes in population parameters can provide early warning signs of negative impacts. In tropical forests, where habitat loss and fragmentation are vast, such indicators are of high relevance for directing conservation efforts before effects are irreversible. Most of our knowledge from tropical ecosystems originates from community level surveys, whereas our understanding of the influence of habitat conversion on vital rates of species is limited. This study focused on the influence of anthropogenic habitat fragmentation on the survival probability and abundance of three leaf-litter frog species (Rhinella ornata, Ischnocnema guentheri and I. parva) in forest patches of the Atlantic rainforest of South-east Brazil compared to a continuous forest. The species differ in their matrix tolerance: high for R. ornata and low for I. guentheri and I. parva and, thus, we examined whether their survival and abundance correspond to this classification. Ischnocnema guentheri showed highest abundances in all study sites and low mortality in the forest patches compared to the continuous forest; I. parva was encountered only in isolated fragments, with very low mortality in one isolated fragment; and the matrix tolerant species had generally low abundance and showed no clear pattern in terms of mortality in the different sites. Our counter-intuitive results show that even matrix sensitive amphibian species may show high abundance and low mortality in small forest patches. Therefore, these patches can be of high value for amphibian conservation regardless of their degree of matrix aversion. Landscape level conservation planning should not abandon small habitat patches, especially in highly fragmented tropical environments.

Since 2012, the number of described species in the carnivorous marsupial genus Antechinus has increased by 50%. The present thesis aimed to collect and analyse fundamental ecological data for one newly described species, the black-tailed dusky antechinus, Antechinus arktos, about which virtually nothing was known. Population ecology and geographic range of the species was used to determine conservation status. The foundational ecological information detailed in this thesis concerning breeding biology, diet, activity patterns and optimal detection methods, will assist in planning future conservation initiatives of this endangered marsupial.

Adult sex ratio (ASR, the proportion of males in the adult population) is a central concept in population and evolutionary biology, and is also emerging as a major factor influencing mate choice, pair bonding and parental cooperation in both human and non-human societies. However, estimating ASR is fraught with difficulties stemming from the effects of spatial and temporal variation in the numbers of males and females, and detection/capture probabilities that differ between the sexes. Here, we critically evaluate methods for estimating ASR in wild animal populations, reviewing how recent statistical advances can be applied to handle some of these challenges. We review methods that directly account for detection differences between the sexes using counts of unmarked individuals (observed, trapped or killed) and counts of marked individuals using mark-recapture models. We review a third class of methods that do not directly sample the number of males and females, but instead estimate the sex ratio indirectly using relationships that emerge from demographic measures, such as survival, age structure, reproduction and assumed dynamics. We recommend that detection-based methods be used for estimating ASR in most situations, and point out that studies are needed that compare different ASR estimation methods and control for sex differences in dispersal.This article is part of the themed issue 'Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies'.

Linking dispersal to population growth remains a challenging task and is a major knowledge gap, for example, for conservation management. We studied relative roles of different demographic rates behind population growth in Siberian flying squirrels in two nest-box breeding populations in western Finland. Adults and offspring were captured and individually identifiable. We constructed an integrated population model, which estimated all relevant annual demographic rates (birth, local [apparent] survival, and immigration) as well as population growth rates. One population (studied 2002–2014) fluctuated around a steady-state equilibrium, whereas the other (studied 1995–2014) showed a numerical decline. Immigration was the demographic rate which showed clear correlations to annual population growth rates in both populations. Population growth rate was density dependent in both populations. None of the demographic rates nor the population growth rate correlated across the two study populations, despite their proximity suggesting that factors regulating the dynamics are determined locally. We conclude that flying squirrels may persist in a network of uncoupled subpopulations, where movement between subpopulations is of critical importance. Our study supports the view that dispersal has the key role in population survival of a small forest rodent.

Adult sex ratio (ASR, the proportion of males in the adult population) is a central concept in population and evolutionary biology, and is also emerging as a major factor influencing mate choice, pair bonding and parental cooperation in both human and non-human societies. However, estimating ASR is fraught with difficulties stemming from the effects of spatial and temporal variation in the numbers of males and females, and detection/capture probabilities that differ between the sexes. Here, we critically evaluate methods for estimating ASR in wild animal populations, reviewing how recent statistical advances can be applied to handle some of these challenges. We review methods that directly account for detection differences between the sexes using counts of unmarked individuals (observed, trapped or killed) and counts of marked individuals using mark–recapture models. We review a third class of methods that do not directly sample the number of males and females, but instead estimate the sex ratio indirectly using relationships that emerge from demographic measures, such as survival, age structure, reproduction and assumed dynamics. We recommend that detection-based methods be used for estimating ASR in most situations, and point out that studies are needed that compare different ASR estimation methods and control for sex differences in dispersal. This article is part of the themed issue ‘Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies’.

Estimates of dynamic rate functions for riverine channel catfish, Ictalurus punctatus (Rafinesque), populations are limited. The open nature and inherent difficulty in sampling riverine environments and the propensity for dispersal of channel catfish impede estimation of population variables. However, contemporary population models (i.e. robust design models) can incorporate the open nature of these systems. The purpose of this study was to determine channel catfish population abundance, survival and size structure and to characterize growth in the lower Platte River, Nebraska, USA. Annual survival estimates of adult channel catfish were 13%–49%, and channel catfish abundance estimates ranged from 8,281 to 24,261 fish within a 10-km sampling reach. Channel catfish were predominantly (90%)

Atlantic Menhaden Brevoortia tyrannus is an economically and ecologically important forage fish. I built a multi-state mark-recapture model to estimate movement, fishing mortality, and natural mortality rates during 1966-1969. Movement from mid-Atlantic regions to North and South Carolina in the winter was lower than previously described, and natural mortality was approximately three times greater than previously estimated. Fishing mortality was highest in North and South Carolina. We evaluated the model’s performance by generating mark-recapture data sets from known values of mortality and movement then fitting the mark-recapture model to those data. The model estimated movement rates > 0.05 to within 33% of the true value even under different scenarios of spatiotemporally distributed releases and fishing effort. Distributing the fishing effort more evenly across regions substantially improved the estimates of movement and fishing mortality, and increasing the number of marked fish released had a small positive effect on accuracy of estimates.

Wings are a key trait underlying the evolutionary success of birds, bats, and insects. For over a century, researchers have studiedthe form and function of wings to understand the determinants of flight performance. However, to understand the evolutionof flight, we must comprehend not only how morphology affects performance, but also how morphology and performanceaffect fitness. Natural and sexual selection can either reinforce or oppose each other, but their role in flight evolution remainspoorly understood. Here, we show that wing shape is under antagonistic selection with regard to sexual and natural selectionin a scrambling damselfly. In a field setting, natural selection (survival) favored individuals with long and slender forewings andshort and broad hindwings. In contrast, sexual selection (mating success) favored individuals with short and broad forewings andnarrow-based hindwings. Both types of selection favored individuals of intermediate size. These results suggest that individualsface a trade-off between flight energetics and maneuverability and demonstrate how natural and sexual selection can operate insimilar directions for some wing traits, that is, wing size, but antagonistically for others, that is, wing shape. Furthermore, theyhighlight the need to study flight evolution within the context of species’ mating systems and mating behaviors.

The purpose of this study was to gather information on the feral pigeon population living in the central business district (CBD) of Butte, MT. Pigeons in the CBD have historically been part of the urban landscape and have contributed to local biodiversity. We report on an aspect of a larger study that was initiated to address complaints from business owners concerning damage caused by pigeons. To better understand feral pigeon population dynamics, we used live trapping, marking with leg bands, and survey transects to study the pigeons’ distribution, habitat selection, and dispersal. Our results thus far indicate minimal dispersal between colonies. Two individuals have shown dispersal movements of up to 6.1 km from the tagging site. Transect surveys revealed an average of 173.3 birds present, with a maximum count of 254 and minimum of 101.

Large carnivores are in decline throughout their range primarily due to anthropogenic influences. This is a concern because these species have high social, economic and ecological value. African lion (Panthera leo) populations are in decline in most parts of the continent and this has been attributed largely to habitat loss, habitat fragmentation, wire snare poaching, black market trafficking in lion parts, retaliatory killings, and poorly regulated trophy hunting. In order to implement effective lion conservation actions, the effect of each factor on lion demography or population dynamics must be well understood. In the past, most studies have used indirect methods to quantify the effects of hunting on lion demography. The temporary ban on lion hunting in Zambia allowed me to study directly how removing a key source of mortality, for males in particular, changed the demography. Using data collected from 2008-2015, I studied how the lion population in and around South Luangwa National Park, Zambia responded to a 3-year moratorium on lion trophy hunting implemented in 2013. For the duration of the study ban, I monitored 386 known individuals in 19 prides and 15 male coalitions. Reproductive activity as represented by cub production appeared to improve after the hunting ban and the number of individually identifiable lions in the study area steadily increased from 88 in 2008 to 197 in 2015. Using a Cormack-Jolly-Seber model, I found that apparent annual survival increased in the absence of hunting for all adult male age classes. The temporary ban on hunting was lifted in 2016 and I recommend that quotas remain conservative in order to allow more time for the population to recover, particularly in the adult male age classes. Better monitoring protocols should also be implemented to promote compliance with hunting regulations.

Large carnivores are in decline throughout their range primarily due to anthropogenic influences. This is a concern because these species have high social, economic and ecological value. African lion (Panthera leo) populations are in decline in most parts of the continent and this has been attributed largely to habitat loss, habitat fragmentation, wire snare poaching, black market trafficking in lion parts, retaliatory killings, and poorly regulated trophy hunting. In order to implement effective lion conservation actions, the effect of each factor on lion demography or population dynamics must be well understood. In the past, most studies have used indirect methods to quantify the effects of hunting on lion demography. The temporary ban on lion hunting in Zambia allowed me to study directly how removing a key source of mortality, for males in particular, changed the demography. Using data collected from 2008-2015, I studied how the lion population in and around South Luangwa National Park, Zambia responded to a 3-year moratorium on lion trophy hunting implemented in 2013. For the duration of the study ban, I monitored 386 known individuals in 19 prides and 15 male coalitions. Reproductive activity as represented by cub production appeared to improve after the hunting ban and the number of individually identifiable lions in the study area steadily increased from 88 in 2008 to 197 in 2015. Using a Cormack-Jolly-Seber model, I found that apparent annual survival increased in the absence of hunting for all adult male age classes. The temporary ban on hunting was lifted in 2016 and I recommend that quotas remain conservative in order to allow more time for the population to recover, particularly in the adult male age classes. Better monitoring protocols should also be implemented to promote compliance with hunting regulations.

The purpose of this study was to gather information on the feral pigeon population living in the central business district (CBD) of Butte, MT. Pigeons in the CBD have historically been part of the urban landscape and have contributed to local biodiversity. We report on an aspect of a larger study that was initiated to address complaints from business owners concerning damage caused by pigeons. To better understand feral pigeon population dynamics, we used live trapping, marking with leg bands, and survey transects to study the pigeons’ distribution, habitat selection, and dispersal. Our results thus far indicate minimal dispersal between colonies. Two individuals have shown dispersal movements of up to 6.1 km from the tagging site. Transect surveys revealed an average of 173.3 birds present, with a maximum count of 254 and minimum of 101.

Large carnivores are in decline throughout their range primarily due to anthropogenic influences. This is a concern because these species have high social, economic and ecological value. African lion (Panthera leo) populations are in decline in most parts of the continent and this has been attributed largely to habitat loss, habitat fragmentation, wire snare poaching, black market trafficking in lion parts, retaliatory killings, and poorly regulated trophy hunting. In order to implement effective lion conservation actions, the effect of each factor on lion demography or population dynamics must be well understood. In the past, most studies have used indirect methods to quantify the effects of hunting on lion demography. The temporary ban on lion hunting in Zambia allowed me to study directly how removing a key source of mortality, for males in particular, changed the demography. Using data collected from 2008-2015, I studied how the lion population in and around South Luangwa National Park, Zambia responded to a 3-year moratorium on lion trophy hunting implemented in 2013. For the duration of the study ban, I monitored 386 known individuals in 19 prides and 15 male coalitions. Reproductive activity as represented by cub production appeared to improve after the hunting ban and the number of individually identifiable lions in the study area steadily increased from 88 in 2008 to 197 in 2015. Using a Cormack-Jolly-Seber model, I found that apparent annual survival increased in the absence of hunting for all adult male age classes. The temporary ban on hunting was lifted in 2016 and I recommend that quotas remain conservative in order to allow more time for the population to recover, particularly in the adult male age classes. Better monitoring protocols should also be implemented to promote compliance with hunting regulations.

In Maryland, commercial blue crab (Callinectes sapidus) harvests are monitored through mandatory, annual harvest reporting, but no monitoring exists for recreational fishers. This study used a large-scale mark-recapture program to assess relative exploitation between the recreational and commercial fishing sectors in 15 harvest reporting areas of Maryland, then incorporated movement information and extrapolated reported commercial harvest data to generate statewide estimates of recreational harvest. Results indicate spatial variation in recreational fishing, with a majority of recreational harvests coming from tributaries of the Western Shore and the Wye and Miles Rivers on the Eastern Shore. Statewide, recreational harvest has remained 8% as large as commercial harvest despite management changes in 2008, and remains a larger proportion (12.8%) of male commercial harvest. In addition, this study provides detailed spatial information on recreational harvest and the first information on rates of exchange of male crabs among harvest reporting areas.

Terrestrial salamanders are major components of ecosystems in eastern North America. One species, the Red-backed Salamander (Plethodon cinereus), may be the most abundant vertebrate throughout its range. Red-backed Salamanders are commonly monitored as indicators of ecosystem health and to assess the effects of forest management practices. In order to address poorly understood aspects of the ecology of Red-backed Salamanders, I conducted a 4-y mark-recapture study of a population in Maryland, resulting in 2,745 records of 752 marked salamanders, along with a complementary genetic analysis of six microsatellite loci. I estimated growth rates and age at sexual maturity using a hierarchical Bayesian model fitted by mark-recapture measurements, then measured home range size and seasonal and annual movement distances by immatures and adults, before and after the experimental removal of 98 conspecifics. Males grow and mature more slowly than females, despite reaching slightly larger asymptotic sizes; they may also face greater competition for space: adult males occupy the largest home ranges and show the largest increase in home range size after the removal of conspecifics. The largest between-year movements were made by individuals as they transitioned from immaturity to maturity. Using mark-recapture population models, I found that estimates of survival, detection, and abundance varied temporally along with the age and sex of the individuals present, both within and among seasons. Encounter probability varied among weekly sampling occasions, and models with separate parameters for each sex were strongly preferred. Survival was approximately the same over winters and summers, and lower for males than for females; this may be an artifact of sex-biased dispersal, as the majority of encountered immature individuals were estimated to be males, with models indicating a pulse of emigration in the fall and an influx of immature males onto the study site in the spring. An FST ra

The Indian Ocean Tuna Tagging Program (IOTTP) provided a unique opportunity to assess the viability of estimating the age of tropical tunas from the micro-structural features of otoliths. Here, we analyzed the length measurements and micro-increment counts collected for 506 sagittal otoliths, of which 343 were chemically marked with oxytetracycline, for bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares). Our results show that the otoliths of tropical tunas grow more slowly than the rest of the body. Our findings confirm that both yellowfin and juvenile bigeye deposit daily increments in their otoliths, though ages are underestimated for large bigeye (>100 cm) when derived from micro-increment counts. Our results also indicate that skipjack otoliths are not suitable for age estimations during the adult phase, as evidenced by the poor agreement between micro-increment counts and days-at-liberty. We hypothesize that the income breeding strategy of skipjack could explain the variability observed in the deposition rates. Due to their complex micro-structural patterns, the reading of tropical tuna otoliths requires a degree of interpretation that can result in poor count precision and large variability in micro-increment counts, both among and within teams of readers. Age estimates were found to vary between readers, a factor which can eventually affect growth estimates and ultimately, impact on fisheries management decisions and outcomes. To address this, we recommend that reference collections of otoliths are developed, with a view to standardizing the reading process. Further, alternative methods, such as annual age estimations (as opposed to daily), and alternative structures, such as dorsal spines for skipjack, should be used to improve the accuracy of age estimations and the speed with which they can be made.

A large, but poorly studied, bottlenose dolphin community, Tursiops truncatus, inhabits coastal waters of Normandy (Normano-Breton Gulf, English Channel, France). In this study, the social structure and abundance of this community were assessed using photo-identification techniques. Like other bottlenose dolphin communities worldwide, this resident community has a fission–fusion social structure with fluid associations among individuals (half-weight index = 0.10). Association patterns were highly variable as indicated by a high social differentiation (S = 0.95±0.03). The majority of associations were casual, lasting days to months. However, individuals exhibited also a smaller proportion of long-term relationships. A mean group size of 26 was large compared with other resident coastal communities, and variable, ranging from 1 to 100, which could be the results of ecological conditions, in particular resource predictability and availability. Analyses also showed that the community was organized in 3 social clusters that were not completely isolated from each other. Abundance was estimated at 420 dolphins (95% confidence interval: 331–521), making this coastal community one of the largest identified along European coastlines. Because human activities in the Gulf are expected to increase in the upcoming years, long-term demographic monitoring of this dolphin community will be critical for its management.

The federally endangered Cumberlandian combshell (Epioblasma brevidens) was propagated and reared to taggable size (5-10 mm), and released to the Powell River, Tennessee, to augment a relict population. Methodology using passive integrated transponder (PIT) tags on these mussels greatly facilitated the detection process. The overall mean detection probability and survival rate of released individuals reached 97.8 to 98.4% and 99.7 to 99.9% (per month), respectively, during nine successive recapture occasions in the 2-year study period, regardless of seasonality. Nonhierarchical models and hierarchical models incorporating individual and seasonal variations through a Bayesian approach were compared and resulted in similar performance of prediction for detection probability and survival rate of mussels. This is the first study to apply the mark-recapture method to laboratory-reared mussels using PIT tags and stochastic models. Quantitative analyses for individual heterogeneity allowed examination of demographic variance and effects of heterogeneity on population dynamics, although the individual and seasonal variations were small in this study. Our results provide useful information in implementing conservation strategies of this faunal group and a framework for other species or similar studies.

Evolutionary analyses of population translocations (experimental or accidental) have been important in demonstrating speed of evolution because they subject organisms to abrupt environmental changes that create an episode of selection. However, the strength of selection in such studies is rarely measured, limiting our understanding of the evolutionary process. This contrasts with long-term, mark-recapture studies of unmanipulated populations that measure selection directly, yet rarely reveal evolutionary change. Here, we present a study of experimental evolution of male colour in Trinidadian guppies where we tracked both evolutionary change and individual-based measures of selection. Guppies were translocated from a predator-rich to a low-predation environment within the same stream system. We used a combination of common garden experiments and monthly sampling of individuals to measure the phenotypic and genetic divergence of male coloration between ancestral and derived fish. Results show rapid evolutionary increases in orange coloration in both populations (1 year or three generations), replicating the results of previous studies. Unlike previous studies, we linked this evolution to an individual-based analysis of selection. By quantifying individual reproductive success and survival, we show, for the first time, that males with more orange and black pigment have higher reproductive success, but males with more black pigment also have higher risk of mortality. The net effect of selection is thus an advantage of orange but not black coloration, as reflected in the evolutionary response. This highlights the importance of considering all components of fitness when understanding the evolution of sexually selected traits in the wild.