Anthropogenic disturbances, such as military training, potentially affect mountain ungulate populations. Assessing the spatiotemporal occupancy or habitat use of a wildlife population can assist with planning of potentially disrupting activities. Currently, military training is expanding into potential Dall's sheep (Ovis dalli dalli) habitat within 2 training areas of Fort Wainwright, Alaska. The 2 study areas included Molybdenum Ridge, a 10‐km long geologically isolated granite ridgeline on the northern periphery of the Alaska Range and Black Rapids Training Area, a steeper and smaller area within the mountain range and bordered by the Delta River. The United States Army requires a better understanding of sheep habitat use in these 2 areas to identify how training could affect the population and to reduce overlap of training and high sheep occupancy. We used an array of 54 spatially balanced camera traps, taking triggered and hourly time lapse images, to determine Dall's sheep habitat use based on seasonal and site covariates. Camera traps operated for a continuous 15‐month sampling period and captured nearly 8,000 images of sheep. Our occupancy models indicated that abiotic covariates such as slope, snow depth, and distance to escape terrain were the most important factors determining habitat use. Seasonal differences in habitat use indicated higher use during winter and spring for Molybdenum Ridge, and higher habitat use during the summer for Black Rapids Training Area. Detection probabilities were constant temporally and were higher if the camera was positioned on a wildlife trail versus off trail. Our results suggest that the best opportunity to minimize training interactions with Dall's sheep is to conduct training in early‐July to early‐September, specifically in areas with <60% slope and >500 m from escape terrain. © 2017 The Wildlife Society.
Outdoor recreation is increasingly recognised for its deleterious effects on wildlife individuals and populations. However, planners and natural resource managers lack robust scientific recommendations for the design of recreation infrastructure and management of recreation activities. We reviewed 38 years of research on the effect of non-consumptive recreation on wildlife to attempt to identify effect thresholds or the point at which recreation begins to exhibit behavioural or physiological change to wildlife. We found that 53 of 330 articles identified a quantitative threshold. The majority of threshold articles focused on bird or mammal species and measured the distance to people or to a trail. Threshold distances varied substantially within and amongst taxonomic groups. Threshold distances for wading and passerine birds were generally less than 100 m, whereas they were greater than 400 m for hawks and eagles. Mammal threshold distances varied widely from 50 m for small rodents to 1,000 m for large ungulates. We did not find a significant difference between threshold distances of different recreation activity groups, likely based in part on low sample size. There were large gaps in scientific literature regarding several recreation variables and taxonomic groups including amphibians, invertebrates and reptiles. Our findings exhibit the need for studies to measure continuous variables of recreation extent and magnitude, not only to detect effects of recreation on wildlife, but also to identify effect thresholds when and where recreation begins or ceases to affect wildlife. Such considerations in studies of recreation ecology could provide robust scientific recommendations for planners and natural resource managers for the design of recreation infrastructure and management of recreation activities.
Identifying the factors that determine the spatial distribution of biodiversity is a major focus of ecological research. These factors vary with scale from interspecific interactions to global climatic cycles. Wetlands are important biodiversity hotspots and contributors of ecosystem services, but the association between proportional wetland cover and species richness has shown mixed results. It is not well known as to what extent there is a relationship between proportional wetland cover and species richness, especially at the sub-continental scale. We used the National Wetlands Inventory (NWI) to model wetland cover for the conterminous United States and the National Land Cover Database to estimate wetland change between 2001 and 2011. We used a Bayesian spatial Poisson model to estimate a spatially varying coefficient surface describing the effect of proportional wetland cover on the distribution of amphibians, birds, mammals, and reptiles and the cumulative distribution of terrestrial endemic species. Species richness and wetland cover were significantly correlated, and this relationship varied both spatially and by taxonomic group. Rather than a continental-scale association, however, we found that this relationship changed more closely among ecoregions. The species richness of each of the five groups was positively associated with wetland cover in some or all of the Great Plains; additionally, a positive association was found for mammals in the Southeastern Plains and Piedmont of the eastern U.S. Model results indicated negative association especially in the Cold Deserts and Northern Lakes & Forests of Minnesota and Wisconsin, though these varied greatly between groups. Our results highlight the need for wetland conservation initiatives that focus efforts at the level II and III ecoregional scale rather than along political boundaries.
Evaluating sympatric habitat use of a mammal community can help determine intra- and inter-guild interactions and identify important habitats, potentially improving the management of these communities with a changing climate. Increasingly variable climatic patterns in Alaska, USA, are raising concerns of mismatched phenologies and altered ecosystem structures. We studied the occupancy of 10 mammal species over 15 months, via camera traps, occupying alpine areas of the Alaska Range in interior Alaska, from 2013 to 2014. We tested hypotheses about how habitat use of these species within and between groups varied by spatial and temporal covariates. Furthermore, we modeled two-species occupancy of brown bears (Ursus arctos Linnaeus, 1758) and gray wolves (Canis lupus Linnaeus, 1758) against different potential prey species. Our results suggest that medium-sized and large herbivore use was positively correlated with fine-scale covariates including rock, forb, and graminoid coverage. Large herbivore habitat use was also correlated with abiotic landscape covariates. Detection probabilities of predators and Dall’s sheep (Ovis dalli dalli Nelson, 1884) was improved by camera traps on wildlife trails. Two-species models suggested co-occurrence of habitat use between brown bear – caribou (Rangifer tarandus (Linnaeus, 1758)) and gray wolf – caribou. Results demonstrate the sympatric habitat use by multiple groups of mammals within Alaskan alpine ecosystems and the importance of incorporating multiple groups and spatial scales when making management decisions.
We used citizen science and inexpensive methodology to assess the distribution of the jungle cat Felis chaus, a relatively common species in Sri Lanka but the least studied of the four wild cat species occurring in the country. We obtained three types of records of the jungle cat: geo-referenced photographs of the species from the public; sightings obtained from print and social media, and provided via an online sighting form; and sightings by field biologists. We combined the 112 unique records obtained in this way with the 21 records from the 2012 National Red List distribution map of the species, and used MaxEnt to predict habitat suitability for the species. The new sightings were primarily in drier regions, expanding the known extent of occurrence for this species in Sri Lanka. Of the new sightings, 7.1% were road kills. Distance to nearest riverine forest, annual precipitation and distance to the nearest reservoir were the most important variables explaining habitat suitability. These findings validate our hypotheses that the species is more widespread than demonstrated previously and also ranges in human-dominated landscapes outside protected areas. Our study provides a model for how ecological and behavioural information for common species can be obtained inexpensively and incorporated into species distribution models. Studies of species such as the jungle cat, which are neither threatened nor charismatic, will help ensure that we keep common species common.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.