Larger Home Range Sizes Research Articles

Western spotted skunk spatial ecology in the temperate rainforests of the Pacific Northwest

AbstractA major threat to small mammalian carnivore populations is human‐induced land use change, but conservation and management are inhibited by limited knowledge about their ecology and natural history. To fill a key knowledge gap of the western spotted skunk (Spilogale gracilis), we investigated their spatial ecology at the landscape and home range scale in the temperate rainforests of the Oregon Cascades during 2017–2019. For the landscape scale analysis, we used detections of western spotted skunks at 112 baited camera traps and fitted a dynamic occupancy model to investigate spatial distribution and drivers of inter‐seasonal and inter‐annual changes in occupancy. Concurrently, we radio‐collared 25 spotted skunks (9 female, 16 male) and collected 1583 relocations. Using continuous‐time movement models, we estimated large home range sizes for both male and female spotted skunks, relative to their body mass, and highly overlapping home ranges that indicated a lack of territoriality. Using these home ranges, we fitted a resource selection function using environmental covariates that we assigned to various hypotheses such as resources, predator avoidance, thermal tolerance, and disturbance. Overall, western spotted skunks were widely distributed across our study area (seasonal occupancy up to 63.7 ± 5.3%) and highly detectable (weekly detection probability = 41.2%). At both spatial scales, spotted skunks selected wetter areas and local valleys, which we attributed to areas with more food resources. At the home range scale, spotted skunks selected locations with lower predation risk and areas surrounded by more previously logged forests. In this montane environment, inter‐seasonal contractions in the spatial distributions of spotted skunks were strongly driven by their response to cold temperature and accumulated snow. This was especially evident when seasonal occupancy declined significantly following a severe heavy snow event in February 2019. Given that there is little information available on the natural history of the western spotted skunk, these results provide essential information about their ecology to focus future monitoring efforts and may help identify potential threats (e.g., forest management, severe snow events, or wildfires) to this species.

The role of memory-based movements in the formation of animal home ranges.

Most animals live in spatially-constrained home ranges. The prevalence of this space-use pattern in nature suggests that general biological mechanisms are likely to be responsible for their occurrence. Individual-based models of animal movement in both theoretical and empirical settings have demonstrated that the revisitation of familiar areas through memory can lead to the formation of stable home ranges. Here, we formulate a deterministic, mechanistic home range model that includes the interplay between a bi-component memory and resource preference, and evaluate resulting patterns of space-use. We show that a bi-component memory process can lead to the formation of stable home ranges and control its size, with greater spatial memory capabilities being associated with larger home range size. The interplay between memory and resource preferences gives rise to a continuum of space-use patterns-from spatially-restricted movements into a home range that is influenced by local resource heterogeneity, to diffusive-like movements dependent on larger-scale resource distributions, such as in nomadism. Future work could take advantage of this model formulation to evaluate the role of memory in shaping individual performance in response to varying spatio-temporal resource patterns.

Comparison of home range size, habitat use and the influence of resource variations between two species of greater gliders (Petauroides minor and Petauroides volans).

Knowledge of the spatial requirements of a species is fundamental to understanding its environmental requirements. However, this can be challenging as the size of a species' home range can be influenced by ecological factors such as diet and size-dependent metabolic demands, as well as factors related to the quality of their habitat such as the density and distribution of resources needed for food and shelter. Until recently, the genus Petauroides was thought to include only a single species with a widespread distribution across eastern Australia. However, a recent study has provided genetic and morphological evidence supporting Petauroides minor as a distinct northern species. Previous studies have focused on the ecology of P. volans, but there has been inadequate research on P. minor. Data on home range and habitat use were obtained for both species using a combination of techniques including GPS collar locations, radiotelemetry, and spotlighting and comparisons were made using consistent methodology. Home range sizes of P. minor (4.79 ha ± 0.97 s.d., KUD .95) were significantly larger than those of P. volans (2.0 ha ± 0.42 s.d., KUD .95). There were no significant differences between male and female home range sizes in either species. Both species showed site-specific preferences for tree species and for larger diameter trees for both forage and shelter. Tree size and biomass/ha were significantly greater in the P. volans study sites than the P. minor study sites and there was a negative correlation between home range size and eucalypt biomass. Larger home range size is likely driven by the substantial differences in biomass between northern (tropical) and southern (temperate) eucalypt-dominated habitats affecting the quality and quantity of resources for food and shelter. Understanding landscape use and habitat requirements within each species of Petauroides can provide important information regarding limiting factors and in directing conservation and management planning.

Trabecular bone morphology in big cats reflects the complex diversity of limb use but not home range size or daily travel distance.

A relationship exists between mechanical loading and bone morphology. Although studies show a relationship between trabecular bone morphology and locomotor strategy in mammals, none of them have studied trabecular bone morphology in felid species occupying disparate and overlapping habitats. We investigate trabecular bone volume fraction (BVF) in the femoral and humeral heads, and distal tibia of four felid species (mountain lions, jaguars, cheetahs, and leopards) to identify whether there is a relationship between BVF and locomotor behavior. This study's goals are to identify whether felid species with high daily travel distance or large home range size have greater BVF compared with those with small daily travel distance or home range size, and whether BVF is correlated among the three elements of the fore and hindlimb studied. We quantified BVF in micro- and peripheral computed tomography images and found no significant differences across species in the femoral and humeral head (p > 0.05). However, in the distal tibia, results showed that leopards, mountain lions, and cheetahs have significantly greater (p < 0.05) BVF than jaguars. Despite differences in home range size and daily travel distance, the proximal elements did not reflect differences in BVF; however, the distal-most element did, suggesting decreased loading among jaguars. These findings suggest that the observed pattern of trabecular bone morphology is potentially due to the diversity in locomotor strategy of the forelimb. Additionally, these results imply that neither home range size nor daily travel distance are clear indicators of activity levels. A cautious approach is warranted in studying how loading influences trabecular morphology.

Spatio-temporal home range of the dominant rodent species in Mabira central forest reserve, Uganda

BackgroundRodents form the largest order among mammals in terms of species diversity, and home range is the area where an individual normally moves during its normal daily activities. Information about rodent home ranges is paramount in the development of effective conservation and management strategies. This is because rodent home range varies within species and different habitats. In Uganda, tropical high altitude forests such as the Mabira Central Forest Reserve are experiencing continuous disturbance. However, information on rodent home range is lacking. Therefore, a two year Capture-Mark-Release (CMR) of rodents was conducted in the intact forest habitat: Wakisi, regenerating forest habitat: Namananga, and the depleted forest habitat: Namawanyi of Mabira Central Forest Reserve in order to determine the dominant rodent species, their home ranges, and factors affecting these home ranges. The home ranges were determined by calculating a minimum convex polygon with an added boundary strip of 5 m.ResultsOverall, the most dominant rodent species were: Lophuromys stanleyi, Hylomyscus stella, Praomys jacksoni Mastomys natalensis, Lophuromys ansorgei, and Lemniscomys striatus. H. stella dominated the intact forest habitat, while L. stanleyi was the most dominant both in the regenerating and the depleted forest habitats. L. stanleyi had a larger home range in the depleted forest, and the regenerating forest habitats, respectively. In the regenerating forest habitat, M. natalensis had a larger home range size, followed by L. stanleyi, and L. striatus. While in the intact forest habitat, H. stella had the largest home range followed by P. jacksoni. H. stella, L. striatus, L. stanleyi, M. natalensis, and P. jacksoni were most dominant during the wet season while L. ansorgei was relatively more dominant during the dry season. L. ansorgei, and P. jacksoni had a larger home range in the dry season, and a lower home range in the wet season. H. stella, L. stanleyi, M. natalansis and L.striatus had larger home ranges in the wet season, and lower home ranges in the dry season. The home ranges of the dominant rodent species varied across the three habitats in Mabira central forest reserve ({F}_{(2, 15)}= 6.41, p = 0.000).ConclusionThe significant variation in home ranges of the dominant rodent species in Mabira Central Forest Reserve depending on the type of habitat presupposes that the rodent management strategies in disturbed forest reserves should focus on the type of habitat.

Survival, movements, home range size and dispersal of hares after coursing and/or translocation.

Hare coursing is the pursuit of a hare by dogs for sport. In recent years in Ireland, between 2,900 to 3,700 hares have been caught from the wild (under Government license) and held in captivity for up to 8 weeks. Hares are given a head start and coursed in an enclosed arena by two muzzled greyhounds where the object is not to kill the hare, but judge the dogs on their ability to turn the hare which escapes under a partition through which the dogs cannot follow. Recent licence returns suggest over 99% of hares survive and are released back into the wild. This study aimed to assess survival and behaviour of coursed hares after their release sometimes into unfamiliar territory. Forty hares were tracked using GPS-radio collars for six months after release in a factorial experimental design to test the impact of coursing and translocation on survival, movements, home range size and dispersal. Coursed and uncoursed hares did not differ in observed mortality rates, movements, home range sizes or dispersal distances after release back into the wild though fewer coursed than uncoursed hares were relocated six months after release, due to a combination of collar strap failures and radio silence. Spatial behavior was similar between the cohorts once translocated hares, which moved further and had larger home range sizes during the first four days after release, had settled. Two hares released shortly before sunset were killed in road traffic collisions during their first night. Releasing hares during daylight, preferably as early as possible, may provide time for animals to settle before darkness. Suggestions are made for potential methodological improvements such as the use of cellular (mobile phone) or satellite communication technology mounted on stouter straps to reduce failures and improve relocation rates.

Occupancy and detectability of African crowned eagles in an urban mosaic landscape: The importance of natural forest areas

Diminishing forests as a result of anthropogenic activities continues to impact the persistence of terrestrial species negatively. Raptors are particularly susceptible to human activities because of their low population densities and large home range sizes. In this study, we investigated the occupancy and detection probabilities of the Near-Threatened African crowned eagle (Stephanoaetus coronatus) in Durban, EThekwini Municipality, South Africa. Using point count surveys, we documented the presence/absence of African crowned eagles in 42 sampling sites in the urban mosaic landscape of Durban. We used the presence/absence data to model their occupancy and detection probability in our surveyed sites. The naïve occupancy of African crowned eagles was 0.6, and the estimated occupancy and detection probability were 0.78 + 0.061 and 0.40 + 0.085, respectively. Based on the best models, the occupancy of African crowned eagles was positively influenced by forests (β = 1.24 + 0.69) and negatively influenced by disturbance (β = −1.69 + 0.78) and roads. The detection probability of these eagles was positively influenced by disturbance (β = 0.34 + 0.29) and the presence of exotic tree plantations (β = 0.33 + 0.47) and negatively influenced by the type of surrounding settlements (i.e., urban or rural) (β = −0.59 + 0.43). Based on the averaged models, occupancy is positively influenced by forests (β = 0.15 + 1.48) and negatively influenced by roads (β = −0.05 + 0.34), building density (β = −0.07 + 0.79) and disturbance (β = −0.24 + 3.36). Detection probability is negatively influenced by surrounding settlement (β = −0.12 + 0.41) and positively influenced by disturbance (β = 0.04 + 3.21) and plantations (β = 0.01 + 0.12). Overall, our results showed the persistence of African crowned eagles in the urban mosaic landscape as a consequence of natural and managed green spaces, especially forests. This highlighted the importance of natural forests and exotic tree plantations in ensuring the survival and thriving of African crowned eagles and the key role these green spaces play in species conservation in this urban mosaic landscape.

Home range variability and philopatry in Cinereous vultures (Aegypius monachus) breeding in Iberia

Large scavengers are strongly dependent on environmental conditions and carrion distribution and abundance, so season and breeding-related factors may influence the spatial ecology of species such as the Cinereous Vulture (Aegypius monachus), the largest European raptor. Iberia holds one of the biggest populations worldwide, but some aspects of the spatial ecology of the species in this region remain unknown. In this study, 17 adult Cinereous Vultures were GPS-tracked in order to study their spatial ecology during the adult phase. The average monthly home ranges (95% Kernel Density Estimation, KDE) and core areas (50% KDE) were 6543 ​± ​19,935 ​km2 and 1174 ​± ​4004 ​km2, respectively. The average monthly home range fidelity ranged between 50 and 73%. Differences in movement-related variables between the seasonal periods (incubation, chick-rearing and non-breeding) were found. During the chick-rearing period, the monthly accumulated distance was higher than during the other periods: 3316 ​± ​1108 (chick-rearing) vs. 1621 ​± ​622 (incubation) vs. 1726 ​± ​1159 ​km per month (non-breeding). Additionally, large home range sizes were more frequent during the chick-rearing period. There are two likely causes for these seasonal differences. Firstly, chick-rearing entails a higher energetic expenditure by the parental individuals in foraging activities, so larger movements and foraging areas are expected during this period. Secondly, the flight is favoured during spring and summer due to environmental conditions. Matching chick-rearing and warm months is a great evolutionary advantage for soaring-gliding raptors, as it allows them to cover larger areas with low energy expenditure. Furthermore, six individuals tagged as nestlings highlight the philopatric behaviour of the species: vultures settle their breeding areas 54 ​± ​51 ​km from their natal nest (range ​= ​9–138 ​km).

Severe environmental conditions create severe conflicts: A novel ecological pathway to extreme coyote attacks on humans

Abstract Identifying the circumstances and causes of carnivore attacks on humans is important for prevention of future incidents as well as employing effective wildlife management strategies. Cape Breton Highlands National Park (CBHNP) in Nova Scotia has experienced multiple attacks by coyotes Canis latrans on humans, including a fatal attack on an adult in 2009. Here we use a combination of data on space use and diet collected from 2011 to 2013 to reveal that limited resources and a reliance on a large ungulate (moose, Alces americanus) as the mechanism leading to aggression by coyotes in CBHNP. Resident coyotes exhibited large home range sizes (mean = 77.5 km2) indicative of limited resources and spatiotemporal avoidance of human activity. Carbon (δ13C) and nitrogen (δ15N) isotope values of sub‐sampled coyote whiskers (n = 32), which provide a longitudinal record of diet over the months before collection, revealed little intra‐ and inter‐individual variation with nearly all individuals specializing on moose, a pattern that agrees with indices of natural resource availability. Specifically, stable isotope mixing models show that moose was the most important prey for most coyotes (25/32), representing between 41% and 78% of dietary inputs. Only four coyotes exhibited use of anthropogenic resources (human foods), and only one of seven coyotes involved in attacks on people had been consuming human foods before the attacks. Synthesis and Applications: We have described a unique ecological system in which a generalist carnivore has expanded its niche to specialize on a large prey species, with the unfortunate consequence of also expanding pathways to conflicts with people. Our results suggest extreme unprovoked predatory attacks by coyotes on people are likely to be quite rare and associated with unique ecological characteristics. Extreme management actions such as bounties are unnecessary, but managers may need to employ hazing or lethal removal earlier in the conflict process than under normal circumstances. Also, users of these areas should be made aware of the risks coyotes pose and encouraged to take precautions.

Movement, Home Range Size, and Habitat Use of Eastern Black-Tailed Rattlesnakes (Crotalus ornatus) in the Northern Chihuahuan Desert

Despite its wide distribution throughout the northern Chihuahuan Desert, extraordinarily little is known about the ecology or behavior of Eastern Black-tailed Rattlesnakes (Crotalus ornatus). The primary literature for Black-tailed Rattlesnakes was largely based on research conducted on the former conspecific (C. molossus); thus, the revalidation of C. ornatus widened the void in our understanding of the species. The aim of this study was to elucidate movement patterns, home range size, and habitat use by C. ornatus in the northern Chihuahuan Desert of far West Texas. Radiotelemetry was used to monitor individual snakes for at least one active season (March–October) from May 2015 through August 2018. Mean (±1 SE) home range size for all individuals was 22.84 ± 4.49 ha and mean daily distance moved was 9.28 ± 0.93 m/d. Male snakes had larger home range sizes, larger core use areas, and greater daily distance moved than did female snakes. On a monthly basis, male movement peaked in August and female movement was statistically similar throughout the active season. Multinomial logit models were used to analyze habitat use patterns of C. ornatus, while controlling for snake, habitat availability, and season. Despite limited availability within snake home ranges, most observations of snakes occurred in arroyos or on rocky slopes. Microhabitat was also used nonrandomly, with snakes seeking cover in rocky refugia or under dense vegetation, rather than in areas containing high proportions of gravel or plant litter. This study presents the first detailed information about habitat and microhabitat use, along with patterns of movement and home range size for the recently revalidated C. ornatus.

Nocturnal space and habitat use by Garden Dormice in an urban area in Germany

The Garden Dormouse (Eliomys quercinus) is currently disappearing from parts of its former range. While its population is declining in many parts of Germany, a stable occurrence is found in the city of Wiesbaden. A radio telemetry study was conducted to investigate nocturnal activity and habitat use. Three males and one female were tracked for six weeks from May to July 2021. Males weighed 85 ± 15 g (n = 6), females 63 ± 8 g (n = 2). Home ranges were calculated using the minimum convex polygon (MCP) method. Males had larger home range sizes (MCP100: 2.69 ± 1.8 ha, n = 3) than females (0.53 ha, n = 1). The home ranges of males overlapped. Males regularly crossed roads up to 16 m wide. Animals exhibited nocturnal behavior with sporadic activity at dusk. Garden Dormice preferred structures with more than 75 % cover from a bird's eye view and 50 % cover when viewed from the side. Broad hedges were strongly preferred over single shrubs and trees or structures without vegetation. They were used by the animals for foraging, mating, as a place for other interactions, and as protected pathways through the habitat. The smaller home range sizes compared to previous studies may be due to good food availability in the city. Animals also seem to benefit from continuous habitat and high levels of plant cover. Recommended conservation measures include maintaining and promoting broad hedges and habitat connectivity.

Understanding continent-wide variation in vulture ranging behavior to assess feasibility of Vulture Safe Zones in Africa: Challenges and possibilities

Protected areas are intended as tools in reducing threats to wildlife and preserving habitat for their long-term population persistence. Studies on ranging behavior provide insight into the utility of protected areas. Vultures are one of the fastest declining groups of birds globally and are popular subjects for telemetry studies, but continent-wide studies are lacking. To address how vultures use space and identify the areas and location of possible vulture safe zones, we assess home range size and their overlap with protected areas by species, age, breeding status, season, and region using a large continent-wide telemetry datasets that includes 163 individuals of three species of threatened Gyps vulture. Immature vultures of all three species had larger home ranges and used a greater area outside of protected areas than breeding and non-breeding adults. Cape vultures had the smallest home range sizes and the lowest level of overlap with protected areas. Rüppell's vultures had larger home range sizes in the wet season, when poisoning may increase due to human-carnivore conflict. Overall, our study suggests challenges for the creation of Vulture Safe Zones to protect African vultures. At a minimum, areas of 24,000 km2 would be needed to protect the entire range of an adult African White-backed vulture and areas of more than 75,000 km2 for wider-ranging Rüppell's vultures. Vulture Safe Zones in Africa would generally need to be larger than existing protected areas, which would require widespread conservation activities outside of protected areas to be successful.

Predicting the risk of Alaria alata infestation in wild boar on the basis of environmental factors.

Alaria alata is an emerging parasite that poses a potential risk for those consuming game, pork, snails and frogs. One paratenic host of A. alata that is known to play an important role in its spread through its feeding habitats is the wild boar. However, no statistical analysis of the influence of aquatic environments and carnivores on the occurrence of A. alata in wild boars has yet been performed. The present study combines a small-scale analysis based on hunting districts in the Mazowieckie province with a large-scale analysis based on data for all provinces in Poland. We applied various modeling approaches, including logistic regression and a generalized linear model in order to determine the presence, intensity and prevalence of A. alata. We used the Alaria mesocercariae migration technique (AMT) to estimate the risk of A. alata among wild boar in a given hunting district or province. The small-scale analysis found that mesopredators (red fox (Vulpes vulpes)) and racoon dog (Nyctereutes procyinoides) were likely to influence A. alata infestation of wild boar; however, the effect was weak, probably as a result of the large home range size of these animals. The large-scale analysis found that wetlands influence the prevalence of A. alata in wild boar, with the estimated risk increasing in the north of the country; this finding is consistent with other studies. Our findings indicate that the occurrence of A. alata in wild boar requires analysis on many levels, and environmental factors play a key role in risk assessment.

A case of polygyny in the Bornean white-bearded gibbon (Hylobates albibarbis)

Abstract Gibbons (family Hylobatidae) typically form groups that encompass a single breeding pair. Here, we present the first evidence of polygyny (where a single male has more than one female mate) in the Bornean white-bearded gibbon (Hylobates albibarbis). In July 2014, an adult female yet to have emigrated from her natal group gave birth to an infant, bringing the total group size to six individuals (one adult male, two adult females, one subadult female, and two infant females). Forty months later in November 2017, the same female gave birth to a second infant. Between July 2014 and April 2018, the two breeding females within the group remained mutually tolerant of each other, often singing the characteristic female vocalisation, the great call, in unison, until the eldest adult female dispersed in November 2018. We explore possible reasons behind this group’s mating system flexibility by examining dispersal limitation due to environmental constraints, factors associated with a large home range size, mutual tolerance between females, and a lack of mating opportunities.

Home Range and Space Use of Northern Bobwhite Under Two Different Management Models in Southwestern Missouri

Northern bobwhite (Colinus virginianus; hereafter, bobwhite) management in Missouri, USA has traditionally been focused on providing an interspersion of grass, crop, old field, and woody cover juxtaposed to disked idle areas and food plots to maintain bobwhite populations. This traditional model is implemented with the goal of providing all essential habitat components within 40-acre blocks throughout a larger area used by a population. While this model can produce usable bobwhite space in agriculture-dominated landscapes, it may not be the most effective or efficient approach to producing and maintaining bobwhite in grassland-dominated landscapes. In southwestern Missouri native tallgrass prairie conservation areas are managed primarily with historical ecological processes, such as fire and grazing, to produce the desired patchy habitat mosaic. Additionally, it has been on these native tallgrass prairie conservation areas that managers have seen the most stable and productive bobwhite populations. Over a 5-year period (2014–2018) we quantified movements of northern bobwhite on 3 traditionally managed areas (n = 185) and on 3 managed native tallgrass prairie conservation areas (n = 211) to determine whether home range sizes and space use differed between these two management models. We used the 6-month (Apr–Sep) breeding period to determine core area, home range, mean movement rate, and maximum distance moved. Overall (pooled) home ranges of bobwhite did not differ significantly between traditional and grassland managed areas; however, there were significant yearly differences between management models and study areas. Males generally had larger home range sizes and had higher movement rates than females. For the 5 years of the study few birds made long-distance movements (>1.6 km; 3%), and all remained relatively close to capture locations in winter (Feb–Mar). For both traditional and grassland managed areas, bobwhite selected for areas that had disturbance (fire and grazing) in the last 2 years and for the native grassland vegetation type. These findings suggest that areas managed under the grassland management model provide preferred habitat for bobwhite and could result in significant improvement in habitat quality for tallgrass prairie wildlife.

Sex and Age Effects on Monk Parakeet Home-Range Variation in the Urban Habitat

Home-range size is a key aspect of space-use, and variation in home-range size and structure may have profound consequences for the potential impact of damage and control strategies for invasive species. However, knowledge on home-range structure of naturalized parrot species is very limited. The aim of this study was to quantify patterns of home-range variation according to sex and age of the monk parakeet Myiopsitta monachus, an invasive parakeet in Europe. Mean kernel home-range size was 12.4 ± 1.22 ha (range 1.7–74.1 ha; N = 73 birds). Juveniles had a larger home-range size than adults, but sexes did not differ in kernel home-range size. The mean maximum distance moved by monk parakeets was 727 ± 37.0 m (range: 150–1581 m), and it was not dependent on either the sex or age of the birds. Having a small home range is one of the conditions for the feasible eradication of an invasive species; hence, the small home range of urban monk parakeets that we report here is good news for pest managers. However, this small home-range size can limit the effectiveness of culling operations with traps or feeders with contraceptives or poison, and other alternatives, such as funnel nets or traps, should be used.

Assessing African Vultures as Biomonitors and Umbrella Species

African vulture populations are rapidly declining, yet funding and other resources available for their conservation are limited. Improving our understanding of which African vulture species could best serve as an umbrella species for the entire suite of African vultures could help conservationists save time, money, and resources by focusing their efforts on a single vulture species. Furthermore, improving our understanding of the suitability of African vultures as biomonitors for detecting environmental toxins could help conservation authorities to detect changes in ecosystem health. We used a systematic approach based on criteria selected a priori to objectively evaluate the potential of each of the 10 resident African vulture species as (i) an umbrella species for all of the African vulture species, and (ii) an avian biomonitor. For each criterion, we scored the respective African vulture species and summed the scores to determine which species was best suited as an umbrella species and as an avian biomonitor. Our results showed that, overall, certain aspects of vulture ecology (large population sizes, large body sizes, long lifespans, and their ability to be monitored over numerous seasons) support their suitability as biomonitors, while other ecological traits, including their diets and the public's perceptions of vultures, could diminish their suitability. The White-backed Vulture (Gyps africanus) was the best fit of the 10 vulture species in our assessment as both an avian biomonitor and an umbrella species for all African vulture species. Meanwhile, significant knowledge gaps for other species inhibit their utility as biomonitors. Due to their large home-range sizes, African vultures may only be useful as biomonitors at a regional scale. However, there could be value in using the White-backed Vulture as an umbrella species, as an aid to conserve the entire suite of African vulture species.

Risk perception and tolerance shape variation in agricultural use for a transboundary elephant population.

To conserve wide-ranging species in human-modified landscapes, it is essential to understand how animals selectively use or avoid cultivated areas. Use of agriculture leads to human-wildlife conflict, but evidence suggests that individuals may differ in their tendency to be involved in conflict. This is particularly relevant to wild elephant populations. We analysed GPS data of 66 free-ranging elephants in the Serengeti-Mara ecosystem to quantify their use of agriculture. We then examined factors influencing the level of agricultural use, individual change in use across years and differences in activity budgets associated with use. Using clustering methods, our data grouped into four agricultural use tactics: rare (<0.6% time in agriculture; 26% of population), sporadic (0.6%-3.8%; 34%), seasonal (3.9%-12.8%; 31%) and habitual (>12.8%; 9%). Sporadic and seasonal individuals represented two-thirds (67%) of recorded GPS fixes in agriculture, compared to 32% from habitual individuals. Increased agricultural use was associated with higher daily distance travelled and larger home range size, but not with age or sex. Individual tactic change was prevalent and the habitual tactic was maintained in consecutive years by only five elephants. Across tactics, individuals switched from diurnal to nocturnal activity during agricultural use, interpreted as representing similar risk perception of cultivated areas. Conversely, tactic choice appeared to be associated with differences in risk tolerance between individuals. Together, our results suggest that elephants are balancing the costs and benefits of crop usage at both fine (e.g. crop raid events) and long (e.g. yearly tactic change) temporal scales. The high proportion of sporadic and seasonal tactics also highlights the importance of mitigation strategies that address conflict arising from many animals, rather than targeted management of habitual crop raiders. Our approach can be applied to other species and systems to characterize individual variation in human resource use and inform mitigations for human-wildlife coexistence.

Varying genetic imprints of road networks and human density in North American mammal populations.

Road networks and human density are major factors contributing to habitat fragmentation and loss, isolation of wildlife populations, and reduced genetic diversity. Terrestrial mammals are particularly sensitive to road networks and encroachment by human populations. However, there are limited assessments of the impacts of road networks and human density on population‐specific nuclear genetic diversity, and it remains unclear how these impacts are modulated by life‐history traits. Using generalized linear mixed models and microsatellite data from 1444 North American terrestrial mammal populations, we show that taxa with large home range sizes, dense populations, and large body sizes had reduced nuclear genetic diversity with increasing road impacts and human density, but the overall influence of life‐history traits was generally weak. Instead, we observed a high degree of genus‐specific variation in genetic responses to road impacts and human density. Human density negatively affected allelic diversity or heterozygosity more than road networks (13 vs. 5–7 of 25 assessed genera, respectively); increased road networks and human density also positively affected allelic diversity and heterozygosity in 15 and 6–9 genera, respectively. Large‐bodied, human‐averse species were generally more negatively impacted than small, urban‐adapted species. Genus‐specific responses to habitat fragmentation by ongoing road development and human encroachment likely depend on the specific capability to (i) navigate roads as either barriers or movement corridors, and (ii) exploit resource‐rich urban environments. The nonuniform genetic response to roads and human density highlights the need to implement efforts to mitigate the risk of vehicular collisions, while also facilitating gene flow between populations of particularly vulnerable taxa.

Patterns and drivers of genetic diversity among Felidae species

Since the late Pleistocene, species in the order Carnivora have experienced a drastic reduction in their populations and distributions. However, the global genetic diversity patterns among terrestrial carnivores have not been investigated. Using felid species as model, we characterized the genetic variation within their populations among continents, between tropical and non-tropical regions, and in relation to human activities. We then evaluated how species traits influence the observed patterns of interspecific genetic diversity. Through data collected from 135 population genetic studies conducted on 28 wild felid species (70% of the described species), data analyses using GLMM modelling showed that the populations in Africa and South America have significantly higher heterozygosity and allelic richness than those in other continents. The Asiatic lions have the least genetic diversity compared to other felids in the world. Threatened species have significantly lower genetic diversity compared to low-risk species as predicted. However, genetic diversity was not related to species body mass or geographic range. We found generation length to be an important variable explaining genetic diversity variation, in which species with short generation length have reduced genetic diversity. Furthemore, the combination of generation length, habitat and home range size captures the variation in heterozygosity significantly better. Species dependent on closed-habitat and with large home range size have reduced heterozygosity compared to their counterparts. Our results allow to identify priority felid species vulnerable to loss of genetic diversity for further conservation studies, and provide an insight into the possible genetic consequences of the late Pleistocene extinctions.