Wildlife Interactions within Highway Underpasses

Highway underpasses are a common management tool used to lessen wildlife-vehicle collisions on roadways. Despite their widespread use, the effects of predator-prey interactions and human disturbances on wildlife within underpasses have not been well studied. To understand the effect of species interactions and human disturbances on wildlife traveling through underpasses, we analyzed camera data from 3 underpasses in Hallelujah Junction Wildlife Area, Sierra County, California, USA, from June 2017 to December 2018. We recorded 3,589 detections, which were predominately mule deer (Odocoileus hemionus), rodents, lagomorphs, California quail (Callipepla californica), bobcats (Lynx rufus), mountain lions (Puma concolor), and coyotes (Canis latrans). We used occupancy modeling and daily activity estimates to analyze species' spatial and temporal activity within the underpasses. Predator-prey interactions and human disturbances were among the most important factors that influenced wildlife travel through the underpasses. Mule deer avoided underpasses highly used by mountain lions, and mountain lions followed mule deer daily temporal activity patterns and seasonal activity patterns. These results indicate that predator-prey interactions influenced deer and mountain lion use of the underpasses. Coyotes favored underpasses and seasons with higher rodent and lagomorph presence, suggesting that the presence of prey was also important to coyote use of the underpasses. Coyotes, mountain lions, and bobcats all exhibited either temporal or spatial avoidance of human activity within the underpasses. California quail avoided predators within the underpasses and favored underpasses and times with high human activity. Our study suggests that underpass managers need to closely monitor the effect of predator-prey interactions and human activity on wildlife within underpasses to ensure these interactions do not discourage wildlife from using them. © 2019 The Wildlife Society.     

Estimating Mountain Lion Abundance in Arizona Using Statistical Population Reconstruction

Directly monitoring abundance of cryptic species, such as mountain lions (Puma concolor), over large areas is a challenge for wildlife managers because traditional population estimation techniques may be impractical and expensive. We generated annual estimates of mountain lion abundance in Arizona, USA, for 2004–2018 by employing statistical population reconstruction methods, which use available age-at-harvest data and auxiliary information such as estimated survival rates, harvest probabilities, and hunter effort. Using PopRecon 2.0 software, we estimated that the statewide abundance of all mountain lions including kittens ranged from 1,848 (95% CI = 650–3,046) to 4,661 (95% CI = 393–9,030) during 2004–2018. Abundance for subadults and adults was more stable and precisely estimated, ranging from 1,166 (95% CI = 622–1,709) to 1,715 (95% CI = 872–2,558). Our results suggest a stable statewide mountain lion population. This approach provides a practical and cost-effective option for monitoring Arizona's mountain lion population, and will improve the ability of managers to monitor the population annually to respond to changes in abundance and to evaluate factors that influence mountain lion abundance. © 2019 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.     

The Lion in West Africa Is Critically Endangered

The African lion has declined to <35,000 individuals occupying 25% of its historic range. The situation is most critical for the geographically isolated populations in West Africa, where the species is considered regionally endangered. Elevating their conservation significance, recent molecular studies establish the genetic distinctiveness of West and Central African lions from other extant African populations. Interventions to save West African lions are urgently required. However formulating effective conservation strategies has been hampered by a lack of data on the species'' current distribution, status, and potential management deficiencies of protected areas (PAs) harboring lions. Our study synthesized available expert opinion and field data to close this knowledge gap, and formulate recommendations for the conservation of West African lions. We undertook lion surveys in 13 large (>500 km²) PAs and compiled evidence of lion presence/absence for a further eight PAs. All PAs were situated within Lion Conservation Units, geographical units designated as priority lion areas by wildlife experts at a regional lion conservation workshop in 2005. Lions were confirmed in only 4 PAs, and our results suggest that only 406 (273–605) lions remain in West Africa, representing <250 mature individuals. Confirmed lion range is estimated at 49,000 km², or 1.1% of historical range in West Africa. PAs retaining lions were larger than PAs without lions and had significantly higher management budgets. We encourage revision of lion taxonomy, to recognize the genetic distinctiveness of West African lions and highlight their potentially unique conservation value. Further, we call for listing of the lion as critically endangered in West Africa, under criterion C2a(ii) for populations with <250 mature individuals. Finally, considering the relative poverty of lion range states in West Africa, we call for urgent mobilization of investment from the international community to assist range states to increase management effectiveness of PAs retaining lions.     

Twenty polymorphic microsatellite markers in the Asiatic lion (Panthera leo persica)

The Asiatic lion (Panthera leo persica) is driven to a single habitat in Gir forests in India for its survival. In order to devise adequate conservation and management strategies for this critically endangered species, it is important to characterize its genetic diversity and understand its population structure. Here we report twenty microsatellite loci, in addition to seven reported earlier, from the genome of a pure Asiatic lion. The microsatellite loci described here will provide potentially useful markers for the assessment of genetic variability in the only existing wild population of the Asiatic lions and other big cat species.     

Genetic structure of mountain lion (Puma concolor) populations in California

Analysis of 12 microsatellite loci from431 mountain lions (Puma concolor)revealed distinct genetic subdivision that wasassociated with geographic barriers andisolation by distance in California. Levels ofgenetic variation differed among geographicregions, and mountain lions that inhabitedcoastal areas exhibited less heterozygositythan those sampled inland. The San FranciscoBay and Sacramento-San Joaquin River Delta, theCentral Valley, and the Los Angeles Basinappeared to be substantial barriers to geneflow, and allele frequencies of populationsseparated by those features differedsubstantially. A partial barrier to gene flowappeared to exist along the crest of the SierraNevada. Estimated gene flow was high amongmountain lions inhabiting the Modoc Plateau,the western Sierra Nevada, and northern sectionof the eastern Sierra Nevada. SouthernCalifornia mountain lion populations mayfunction as a metapopulation; however, humandevelopments threaten to eliminate habitat andmovement corridors. While north-south geneflow along the western Sierra Nevada wasestimated to be very high, projected loss andfragmentation of foothill habitat may reducegene flow and subdivide populations. Preservation of existing movement corridorsamong regions could prevent population declinesand loss of genetic variation. This studyshows that mountain lion management andconservation efforts should be individualizedaccording to region and incorporatelandscape-level considerations to protecthabitat connectivity.     

Desert bighorn sheep habitat selection,group size,and mountain lion predation risk

Bighorn sheep (Ovis canadensis) evolved for thousands of years in the presence of numerous predators, including mountain lions (Puma concolor). Bighorn sheep have presumably developed predator avoidance strategies; however, the effectiveness of these strategies in reducing risk of mountain lion predation is not well understood. These strategies are of increasing interest because mountain lion predation on bighorn sheep has been identified as a leading cause of mortality in some sheep populations. Therefore, we investigated how mountain lions affect both bighorn sheep habitat selection and risk of mortality in Arizona, USA. We used 2 approaches to investigate the predator-prey relationship between mountain lions and bighorn sheep. We fit 103 bighorn sheep (81 females and 22 males) with global positioning system radio-collars in 2 Arizona populations from 2013 to 2017, and used a negative binomial resource selection probability function to evaluate whether bighorn sheep selected for habitat features in accordance with presumed predator avoidance strategies, including terrain ruggedness, slope, topographic position, and horizontal obstruction, in 2 seasons (winter and summer). We then estimated how habitat features such as terrain ruggedness, slope, horizontal obstruction, and group size, influence the risk of mortality due to mountain lion predation using an Andersen-Gill proportional hazards model. Generally, both sexes selected areas with lower horizontal obstruction and intermediate ruggedness and slope, but selection patterns differed between seasons and sexes. The use of more rugged areas and steeper slopes decreased the risk of mortality due to mountain lion predation, consistent with presumed predator avoidance strategies. Increased group size decreased risk of bighorn sheep mortality due to mountain lion predation but this effect became marginal at approximately 10 individuals/group. We did not identify a relationship between horizontal obstruction and bighorn sheep mortality risk. Our findings can be used in habitat and population management decisions such as the prioritization of habitat restoration sites or selection of translocation sites. In addition, we suggest that augmentation of low-density bighorn sheep populations may reduce mountain lion predation risk by increasing group size, and that releasing large groups of bighorn sheep in population augmentation and reintroduction efforts may help to reduce mountain lion predation.     

Big Cats in the Big City: Spatial Ecology of Mountain Lions in Greater Los Angeles

Large carnivores can represent the ultimate challenge for conservation in developed landscapes because of their large area requirements and potential for conflict with humans. Some large carnivores such as mountain lions (Puma concolor) can use a wide range of biomes and vegetation types, and in southern California, USA, they persist in metropolitan Los Angeles, a megacity of 18 million people. Understanding how large carnivores use highly altered landscapes is important for their conservation and management. We estimated home range size, landscape use, and landscape selection for mountain lions in the Santa Monica Mountains and surrounding areas for 29 subadult and adult animals from 2002 to 2016, using 128,133 locations from global positioning system (GPS)-collars. Home range size was similar to that reported by other researchers; home ranges averaged 372 km² for adult males and 134 km² for adult females, except for 2 adult males in isolated habitat fragments that maintained 2 of the smallest adult male home ranges ever recorded (24 km² and 54 km²). Mountain lions very rarely entered developed areas, consistently avoided altered open areas such as golf courses, cemeteries, or other landscaped spaces, and showed a positive relationship between home range size and amount of development, all indicating that developed areas have reduced value for mountain lions. Mountain lions from all sex and age classes selected areas closer to development than expected by chance, which could be related to the presence of mule deer (Odocoileus hemionus) or other prey in or adjacent to urbanization. For 2 adult males that occupied home ranges within the most urban portions of our study area, their response to urban development differed strongly across diurnal periods, ranging from avoidance during the day to selection at night. Shrub vegetation types, especially chaparral, were important in terms of habitat use and resource selection, highlighting their importance for conservation of the species in southern California. North America's largest felid can thrive in shrublands and persist even in one of the world's largest cities, although they only very rarely venture into developed areas within that city. © 2021 The Wildlife Society.     

Characterizing habitat suitability for a central‐place forager in a dynamic marine environment

Characterizing habitat suitability for a marine predator requires an understanding of the environmental heterogeneity and variability over the range in which a population moves during a particular life cycle. Female California sea lions (Zalophus californianus) are central‐place foragers and are particularly constrained while provisioning their young. During this time, habitat selection is a function of prey availability and proximity to the rookery, which has important implications for reproductive and population success. We explore how lactating females may select habitat and respond to environmental variability over broad spatial and temporal scales within the California Current System. We combine near‐real‐time remotely sensed satellite oceanography, animal tracking data (n = 72) from November to February over multiple years (2003–2009) and Generalized Additive Mixed Models (GAMMs) to determine the probability of sea lion occurrence based on environmental covariates. Results indicate that sea lion presence is associated with cool ( <14°C ), productive waters, shallow depths, increased eddy activity, and positive sea‐level anomalies. Predictive habitat maps generated from these biophysical associations suggest winter foraging areas are spatially consistent in the nearshore and offshore environments, except during the 2004–2005 winter, which coincided with an El Niño event. Here, we show how a species distribution model can provide broadscale information on the distribution of female California sea lions during an important life history stage and its implications for population dynamics and spatial management.     

Characterization of eight microsatellite loci in Steller sea lions (Eumetopias jubatus)

Steller sea lions (Eumetopias jubatus) are listed as an endangered species in western Alaska and have exhibited a significant population decline throughout their range. Eight microsatellite loci were isolated from genomic DNA libraries. In addition, all these markers were found to be variable in nine individuals of the California sea lion (Zalophus californicus). This panel of markers was developed to analyse population structure in Steller sea lions throughout their range.     

In the absence of a “landscape of fear”: How lions,hyenas, and cheetahs coexist

Aggression by top predators can create a “landscape of fear” in which subordinate predators restrict their activity to low‐risk areas or times of day. At large spatial or temporal scales, this can result in the costly loss of access to resources. However, fine‐scale reactive avoidance may minimize the risk of aggressive encounters for subordinate predators while maintaining access to resources, thereby providing a mechanism for coexistence. We investigated fine‐scale spatiotemporal avoidance in a guild of African predators characterized by intense interference competition. Vulnerable to food stealing and direct killing, cheetahs are expected to avoid both larger predators; hyenas are expected to avoid lions. We deployed a grid of 225 camera traps across 1,125 km² in Serengeti National Park, Tanzania, to evaluate concurrent patterns of habitat use by lions, hyenas, cheetahs, and their primary prey. We used hurdle models to evaluate whether smaller species avoided areas preferred by larger species, and we used time‐to‐event models to evaluate fine‐scale temporal avoidance in the hours immediately surrounding top predator activity. We found no evidence of long‐term displacement of subordinate species, even at fine spatial scales. Instead, hyenas and cheetahs were positively associated with lions except in areas with exceptionally high lion use. Hyenas and lions appeared to actively track each, while cheetahs appear to maintain long‐term access to sites with high lion use by actively avoiding those areas just in the hours immediately following lion activity. Our results suggest that cheetahs are able to use patches of preferred habitat by avoiding lions on a moment‐to‐moment basis. Such fine‐scale temporal avoidance is likely to be less costly than long‐term avoidance of preferred areas: This may help explain why cheetahs are able to coexist with lions despite high rates of lion‐inflicted mortality, and highlights reactive avoidance as a general mechanism for predator coexistence.     

Molecular tracking of mountain lions in the Yosemite valley region in California: genetic analysis using microsatellites and faecal DNA

Twelve microsatellite loci were characterized in California mountain lions (Puma concolor) and sufficient polymorphism was found to uniquely genotype 62 animals sampled at necropsy. Microsatellite genotypes obtained using mountain lion faecal DNA matched those from muscle for all of 15 individuals examined. DNA from potential prey species and animals whose faeces could be misidentified as mountain lion faeces were reliably distinguished from mountain lions using this microsatellite panel. In a field application of this technique, 32 faecal samples were collected from hiking trails in the Yosemite Valley region where seven mountain lions previously had been captured, sampled, and released. Twelve samples yielded characteristic mountain lion genotypes, three displayed bobcat-type genotypes, and 17 did not amplify. The genotype of one of the 12 mountain lion faecal samples was identical to one of the mountain lions that previously had been captured. Three of the 12 faecal samples yielded identical genotypes, and eight new genotypes were detected in the remaining samples. This analysis provided a minimum estimate of 16 mountain lions (seven identified by capture and nine identified by faecal DNA) living in or travelling through Yosemite Valley from March 1997 to August 1998. Match probabilities (probabilities that identical DNA genotypes would be drawn at random a second time from the population) indicated that the samples with identical genotypes probably came from the same mountain lion. Our results demonstrate that faecal DNA analysis is an effective method for detecting and identifying individual mountain lions.     

Measures of giant panda habitat selection across multiple spatial scales for species conservation

Examining ecological processes across spatial scales is crucial as animals select and use resources at different scales. We carried out field surveys in September 2005, March–September 2006, and April 2007, and used ecological niche factor analysis to determine habitat preferences for the giant panda (Ailuropoda melanoleuca) across 4 spatial scales: daily movement, core range, home range, and seasonal elevational migration. We found that giant pandas prefer conifer forest and mixed forest at higher than average elevation (2,157 m) of study area in the 4 scale models. However, we also observed significant scale differences in habitat selection. The strength of habitat preference increased with scale for the 2 disturbed forests (sparse forest and fragmented forest), and decreased with scale for 0–30° gentle slope and south- and north-facing aspect. Furthermore, habitat suitability patterns were scale-dependent. These findings highlight the need to determine species–environment associations across multiple scales for habitat management and species conservation. © 2012 The Wildlife Society.     

‘Site’ing the right reasons: critical evaluation of conservation planning for the Asiatic lion

The resurrection of Asiatic lions (Panthera leo persica) from the brink of extinction is a remarkable conservation success story. Yet, occurrence of lions as a single population makes them vulnerable to extinction from genetic and environmental factors. Asiatic lions exist as a single free ranging population of 360 individuals in Gir Protected Area (PA; about 290 lions) and surrounding satellite areas (68 lions), namely Girnar Wildlife Sanctuary (WLS), coastal areas, hill ranges extending from Mitiyala-Savarkundla-Palitana-Shihor spreading across Junagadh, Amreli and Bhavnagar districts of Gujarat State, India. This paper traces the conservation history, current conservation pressures, and critically evaluates current conservation planning based on lion ecology and existing anthropogenic pressures. Conservation proposals for translocation of lions to alternate habitats in Kuno WLS and Barda WLS are awaiting final implementation. An alternate initiative is aimed at developing satellite lion habitats, improving corridor connectivity, and facilitating natural dispersal and expansion of lion habitats. The paper evaluates human population living within 2 km boundary of lion habitats and between Gir PA and satellite habitats to show that dispersing lions have to cross heavily populated habitations taking refuge in agriculture fields and scattered forest patches. Satellite habitats vary in size from 18 km² (Mitiyala WLS) to 250 km² (scattered forests Hipavadli-Savarkundla-Palitana zone along Shetrunji river) and are inadequate to maintain natural ranging and movement requirements of territorial lions. These habitats are varied in vegetation, terrain, human pressure, and distance to source population. Though satellite lion habitats are important suboptimal habitats for dispersing lions, long-term conservation planning require planned restoration of mosaic habitats for growing populations.     

The significance of African lions for the financial viability of trophy hunting and the maintenance of wild land

Recent studies indicate that trophy hunting is impacting negatively on some lion populations, notably in Tanzania. In 2004 there was a proposal to list lions on CITES Appendix I and in 2011 animal-welfare groups petitioned the United States government to list lions as endangered under their Endangered Species Act. Such listings would likely curtail the trophy hunting of lions by limiting the import of lion trophies. Concurrent efforts are underway to encourage the European Union to ban lion trophy imports. We assessed the significance of lions to the financial viability of trophy hunting across five countries to help determine the financial impact and advisability of the proposed trade restrictions. Lion hunts attract the highest mean prices (US$24,000-US$71,000) of all trophy species. Lions generate 5-17% of gross trophy hunting income on national levels, the proportional significance highest in Mozambique, Tanzania, and Zambia. If lion hunting was effectively precluded, trophy hunting could potentially become financially unviable across at least 59,538 km(2) that could result in a concomitant loss of habitat. However, the loss of lion hunting could have other potentially broader negative impacts including reduction of competitiveness of wildlife-based land uses relative to ecologically unfavourable alternatives. Restrictions on lion hunting may also reduce tolerance for the species among communities where local people benefit from trophy hunting, and may reduce funds available for anti-poaching. If lion off-takes were reduced to recommended maximums (0.5/1000 km(2)), the loss of viability and reduction in profitability would be much lower than if lion hunting was stopped altogether (7,005 km(2)). We recommend that interventions focus on reducing off-takes to sustainable levels, implementing age-based regulations and improving governance of trophy hunting. Such measures could ensure sustainability, while retaining incentives for the conservation of lions and their habitat from hunting.     

Mountain lions on the prairie: habitat selection by recolonizing mountain lions at the edge of their range

Mountain lions (Puma concolor) have historically experienced large‐scale range contractions, but are beginning to recolonize portions of their former range. To reach potential suitable habitats in eastern North America, mountain lions need to move across the grassland and agriculture‐dominated habitats of the Great Plains, which are different from the forested areas associated with mountain lions in western North America. To inform restoration planning in this area, it is important to understand differences in mountain lion habitat selection in this “nontraditional” grassland habitat. We tracked GPS‐collared mountain lions in the Northern Great Plains of Montana and identified movement states (localized or exploratory) using behavioral change point analysis and net‐squared displacement. We compared habitat selection between the different states using step‐selection functions that included several environmental covariates. Similar to elsewhere throughout their range, across both movement states, mountain lions tended to select forested environments that were farther from human development. In contrast to more traditionally occupied mountainous regions, mountain lions in the Great Plains selected areas of lower elevations. They selected areas both near and far from water, but avoided riparian areas and selected more rugged environments when in exploratory movement states. This suggests that mountain lions in the Northern Great Plains are utilizing river corridors, particularly those with rough or broken topography during exploratory phases. To enhance future recolonization and connectivity of mountain lions to the east of our study area, we encourage managers to maintain and restore forest fragments along river corridors in the Great Plains.     

The origin, current diversity and future conservation of the modern lion (Panthera leo)

Understanding the phylogeographic processes affecting endangered species is crucial both to interpreting their evolutionary history and to the establishment of conservation strategies. Lions provide a key opportunity to explore such processes; however, a lack of genetic diversity and shortage of suitable samples has until now hindered such investigation. We used mitochondrial control region DNA (mtDNA) sequences to investigate the phylogeographic history of modern lions, using samples from across their entire range. We find the sub-Saharan African lions are basal among modern lions, supporting a single African origin model of modern lion evolution, equivalent to the 'recent African origin' model of modern human evolution. We also find the greatest variety of mtDNA haplotypes in the centre of Africa, which may be due to the distribution of physical barriers and continental-scale habitat changes caused by Pleistocene glacial oscillations. Our results suggest that the modern lion may currently consist of three geographic populations on the basis of their recent evolutionary history: North African-Asian, southern African and middle African. Future conservation strategies should take these evolutionary subdivisions into consideration.     

Integrating climate and landscape models to prioritize areas and conservation strategies for an endangered arboreal primate

Species distributions are influenced by both climate conditions and landscape structure. Here we propose an integrated analysis of climatic and landscape niche-based models for a forest-dependent primate, the endangered black lion tamarin (Leontopithecus chrysopygus). We applied both climate and landscape variables to predict the distribution of this tamarin and used this information to prioritize strategic areas more accurately. We anticipated that this approach would be beneficial for the selection of pertinent conservation strategies for this flagship species. First, we built climate and landscape niche-based models separately, combining seven algorithms, to infer processes acting on the species distribution at different scales. Subsequently, we combined climate and landscape models using the EcoLand Analysis. Our results suggest that historic and current landscape fragmentation and modification had profoundly adverse effects on the distribution of the black lion tamarins. The models indicated just 2096 km² (out of an original distribution of 92,239 km²) of suitable areas for both climate and landscape. Of this suitable area, the species is currently present in less than 40%, which represents less than 1% of its original distribution. Based on the combined map, we determined the western and southeast regions of the species range to be priority areas for its conservation. We identified areas with high climatic and high landscape suitability, which overlap with the remaining forest fragments in both regions, for habitat conservation and population management. We suggest that areas with high climatic but low landscape suitability should be prioritized for habitat management and restoration. Areas with high landscape suitability and low climatic suitability, such as the Paranapiacaba mountain range should be considered in light of projected climate change scenarios. Our case study illustrates that a combined approach of climatic and landscape niche-based modeling can be useful for establishing focused conservation measures that may increase the likelihood of success.     

Noninvasive genetic sampling allows estimation of capercaillie numbers and population structure in the Bohemian Forest

Wildlife conservation and management of endangered species requires reliable information on the size and structure of populations. One of the flagship species in European wildlife conservation is the forest-dwelling capercaillie (Tetrao urogallus), where several populations are endangered. In the Bohemian Forest, e.g., the population severely declined 30 years ago with only 100 birds remaining in 1985. Subsequently, breeding and release programs were conducted to supplement the local population. The current distribution and population size, however, remained unknown. With recent habitat changes and increasing recreational activities, a reliable population estimate to inform conservation plans was needed. A team of scientists and volunteers collected fresh capercaillie droppings covering an area of about 120,000 ha. We genotyped ten microsatellite loci to estimate the current population size and to determine the population’s spatial and genetic structure. Population size and density estimators revealed a population size of approximately 500 individuals, which is thus one of the two largest relict populations in the low mountain ranges of temperate Europe. The population clustering revealed gene flow across the entire study area. Several genotypes were documented with multiple recaptures at spatial distances between 10 and 30 km additionally corroborating gene flow across the entire landscape of the study area. Males were more closely related than females on small spatial scales up to 3 km, indicating lower dispersal rates in males. We conclude that the population currently appears to have a viable size and shows unrestricted gene flow across state borders and management units of the entire Bohemian Forest. However, long-term viability of this population requires a transboundary strategy to sustainably protect and monitor this isolated capercaillie population in Central Europe.     

四川卧龙国家级自然保护区多空间尺度下绿尾虹雉的生境选择

动物的生境选择具有空间尺度依赖性, 在不同空间尺度上影响生境选择的环境因素有所不同。研究不同空间尺度下动物生境选择的关键影响因子及其季节性变化, 对于全面了解物种的生境资源需求和开展生境保护具有重要意义。绿尾虹雉(Lophophorus lhuysii)是中国特有的高山雉类, 国家一级重点保护野生动物, 具有极高的保护价值。然而, 目前尚未对其不同尺度和时期的生境选择进行过探究。本研究于2019年10月至2020年10月, 在四川卧龙国家级自然保护区的羊角湾、魏家沟和文扎都3个区域共布设15条样线、303个样方, 并结合红外相机监测(176个红外相机位点), 对保护区内绿尾虹雉种群的生境利用状况进行了调查, 使用主成分分析和逻辑斯蒂回归模型分别从景观和微生境两个尺度对繁殖期(3‒8月)和非繁殖期(9月至翌年2月)的生境选择模式进行了分析。结果显示, 在景观尺度上, 在繁殖期和非繁殖期都显著偏好海拔较高(3,700‒ 4,300 m)、坡度较小(27°‒33°)、靠近阳坡、草甸和流石滩比例较高而森林和灌丛比例较低的生境。在微生境尺度上, 绿尾虹雉在繁殖期显著偏好岩石盖度较高的生境; 而非繁殖期则显著偏好草本盖度较高、灌木盖度和落叶盖度较低的生境。研究表明, 绿尾虹雉在景观和微生境尺度上均对生境有明显的选择性, 并且其微生境选择还存在季节性变化, 反映了该物种在生活史不同阶段具有不同的资源需求。本研究丰富了绿尾虹雉的基础生态学信息, 为卧龙及其他自然保护区绿尾虹雉的生境管理和种群保护工作提供了参考。     

Isolation of a novel adenovirus from California sea lions Zalophus californianus

Viral hepatitis associated with adenoviral infection has been reported in California sea lions Zalophus californianus admitted to rehabilitation centers along the California coast since the 1970s. Canine adenovirus 1 (CAdV-1) causes viral hepatitis in dogs and infects a number of wildlife species. Attempts to isolate the virus from previous sea lion hepatitis cases were unsuccessful, but as the hepatitis had morphologic features resembling canine infectious hepatitis, and since the virus has a wide host range, it was thought that perhaps the etiologic agent was CAdV-1. Here, we identify a novel adenovirus in 2 stranded California sea lions and associate the infection with viral hepatitis and endothelial cell infection. Phylogenetic analysis confirmed the classification of the sea lion adenovirus in the Mastadenovirus genus with the most similarity to tree shrew adenovirus 1 (TSAdV-1, 77%). However, as the sea lion adenovirus appeared to be equally distant from the other Mastadenovirus species based on phylogenetic analysis, results indicate that it represents an independent lineage and species. Although sequences from this novel virus, otarine adenovirus 1 (OtAdV-1), show some similarity to CAdV-1 and 2, it is clearly distinct and likely the cause of the viral hepatitis in the stranded California sea lions.