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Evaluating Two Monitoring Methods During Autumn Songbird Migration (Poster)
No full textMigration is an important part of avian life cycles that is not well understood, particularly in the West. Understanding how factors like climate change and habitat condition are affecting migrating populations is limited by our ability to monitor them. We compared two widely used migration monitoring tools to see if they are comparable for detecting apparent abundance. This study evaluated how standard effort mist-netting detections compared to automated recording unit detections. For the 24 species that were detected by both methods, relative abundance was correlated (r = 0.60; SE 0.17). While there is some ability to estimate apparent abundance based on the correlative nature of one method, the target species or project goal may dictate which monitoring method should be applied. Ideally, combining these methods will provide a better and more complementary representation of trends in migrating songbird
Looking Back at 19 Years of Mule Deer Adaptive Harvest Management in FWP Region 6
No full textThe FWP adapted the Mule Deer Adaptative Harvest Management plan in 2001 and since then, mule deer densities within FWP Administrative Region 6 have increased significantly over the last two decades, as estimated through 11 deer trend areas across the region. Due to increasing densities, increased hunting pressure, new disease threats and potential game damage concerns on private lands, the FWP has steadily increased harvest through available antlerless blicenses. The majority of the region is either-sex, general hunting opportunity for both deer species with liberal b-licenses but available b-licenses have fluctuated in the last 19 years, as low as no b-licenses available for two years, to over 6,000 offered across the region in 2019. In recent years, the demand from both landowners and sportsman for increased harvest opportunity and the need to reduce higher concentrations of deer has also increased. Mule deer numbers have thrived under AHM since its inception and the FWP’s objective to maintain deer densities at a more tolerable and closer to average level provides mostly liberal hunting seasons across the region while minimizing landowner conflicts with mule deer and maintaining a healthy population
Mammal Community Response to Cattle Grazing (Poster)
No full textThe impacts of cattle (Bos taurus) grazing on the environment are complex. Chronic overgrazing may inhibit primary productivity and alter vegetation structure and composition, while moderate grazing may increase the quality of vegetation by stimulating new growth and net primary productivity. Numerous studies have estimated the effects of grazing on wildlife demography and behavior, but few have evaluated the effects of grazing on multitrophic communities. Our objective is to identify how squirrel-sized and larger mammals interact with cattle at varying grazing intensities and how cattle affect the structure of the mammal community. Specifically, we aim to determine whether species richness, occurrence, and behavior of mammal species is influenced by the number of cattle, and whether these potential influences cause changes in interspecific interactions among sympatric mammal species. To answer these questions, we set trail cameras 40-50 cm high, unbaited, at random sites within cattle ranches in western Montana representative of the variation in grazing management practices. Throughout spring, summer, and fall, we set trail cameras for at least 21 days at 75 sites per ranch. We will estimate co-occurrence of all potentially interacting mammal species, using a multispecies occupancy model that accounts for imperfect detection, and evaluate how the presence of cattle affects these interactions. We will also monitor species changes in temporal activity patterns in the presence of cattle. Results will identify how mammal communities respond to cattle grazing, which may offer insight into sustainable coexistence among wild and domestic species
Western Bumble Bee Declines in US and Sample Design for Filling Range-Wide Information Gaps
No full textIn recent decades many bumble bee species have declined due to changes in habitat, climate, and pressures from pathogens, pesticides, and introduced species. The western bumble bee (Bombus occidentalis), once common throughout western North America is a species of concern and will be considered for listing by the U.S. Fish and Wildlife Service (USFWS) under the Endangered Species Act (ESA). We attempt here to improve the alignment of data collection and research with USFWS needs to consider redundancy, resiliency, and representation in the upcoming species status assessment. We reviewed existing data and literature on B. occidentalis, highlighting priority topics for research. We used existing data to model changes in B. occidentalis occupancy from 1998 to 2018. The probability of local occupancy in the continental United States declined by 93% over 21 years from 0.81(95%CRI = 0.43, 0.98) in 1998 to 0.06 (95%CRI = 0.02, 0.16) in 2018. The decline in occupancy varied spatially by landcover and other environmental factors. However, we found considerable spatial gaps in recent sampling, with limited sampling in many regions, including most of Alaska, northwestern Canada, and the southwestern U.S. We therefore propose a sampling design to address these gaps to best inform the ESA species status assessment through improved assessment of the spatial drivers of occupancy changes. Finally, we request involvement via data sharing, participation in occupancy sampling with repeated visits to distributed survey sites, and complementary research to address priorities outlined in this paper
Estimating Abundance of Dusky Grouse for Population Monitoring
No full textDusky grouse (Dendragapus obscurus), are a forest grouse species found throughout mountainous regions of western Montana. Despite being a game species, population monitoring has been inconsistent in recent years. Our objective is to develop, test, and evaluate sampling and statistical methods for unbiased population monitoring to inform management. We developed a spatially explicit model of dusky grouse relative habitat suitability in Montana to identify suitable survey sites for population monitoring. Prior to sampling in the field, we conducted statistical simulations to evaluate efficacy of potential survey protocols. Results from the simulations suggested that a minimum of 100 independent sites surveyed three times within a period of closure had the potential to yield unbiased and reasonably precise estimates for regional population abundance. During a pilot study in 2019, we conducted surveys during two sampling periods, spring and summer, within Montana, Fish, Wildlife, and Parks administrative region 3. Field methods included point counts with and without the use of electronic playback and walking transect surveys. We used N-mixture models and distance sampling to estimate abundance, density, and detection for each of the survey methods in each sampling period. We observed significantly more grouse during spring surveys than summer surveys, which yielded more precise estimates of abundance and density. The use of electronic playback calls increased detection probability during spring surveys but had no effect on summer detectability. Future work includes evaluating current and other potential survey protocols using simulations and estimates produced from the pilot stud
Estimating Population Size of Grand Canyon Bighorn Sheep with Scr (Poster)
No full textDesert bighorn sheep are a species of conservation concern and management importance for their symbolism, role as the only ungulate in the desert nutrient cycle, and as a prey and carrion source. The bighorn population in the Grand Canyon (GRCA) represents the largest population managed by the National Park Service on the largest protected habitat on the Colorado Plateau. Bighorn sheep are highly susceptible to pneumonia from contacts with domestic sheep and the first documented occurrence of pneumonia in the GRCA caused a significant decline in survey counts between 2011 and 2014. The disease outbreak occurred during a large-scale, multi-year study of bighorn sheep movement and connectivity by sampling fecal pellets. This created an opportunity to conduct the first estimate of bighorn abundance and disease impacts for the entire GRCA. Thirteen hundred samples from five years were genotyped and analyzed with spatial capture-recapture models to estimate abundance while modeling detection and incorporating environmental constraints. We will discuss top models for detection and density, and describe our approaches for accounting for a linear sample design in this population, reducing the size of confidence intervals with auxiliary data, and estimating movement through the system
Grizzly Bear and Human Use at Moth Aggregation Sites, Wyoming
No full textThe objective of our study was to quantify human-bear interactions associated with moth aggregation sites in the greater Yellowstone ecosystem. Our field work was conducted during the summers of 2017 and 2018, and focused on two of the most human-accessible sites within the Shoshone National Forest, Wyoming. Occupancy surveys of grizzly bears (Ursus arctos horribilis) were conducted and evaluated using a resource selection function to quantify bear use patterns. Human use was quantified through trailhead monitoring, peak log entries, and opportunistic documentation. Interactions were documented through written or verbal surveys at peaks and trailheads. GPS tracking units were distributed at trailheads to quantify human use patterns. Bear and human use patterns were analyzed in ArcMap to identify areas of overlap. We documented 84 and 182 bears and 37 and 39 human use groups in 2017 and 2018, respectively. Bear use was most strongly associated with landcover and temperature, and to a lesser degree terrain ruggedness and curvature, slope, and moisture. Human use was largely concentrated on published routes from internet resources that overlapped predicted high-use bear areas. We documented 18 bear-human interactions, 12 of which were within predicted high-use bear areas. All interactions resulted in bear displacement with no aggressive behavior toward humans. Human use and bear-human interactions appear to be relatively low but will continue to increase with human use, particularly in high-use bear areas. In the future, managers may consider measures to educate visitors or manage human access to promote human safety and minimize disturbance of grizzly bears
Influence of Livestock on Grizzly Bear Habitat Selection
No full textWhen encounters between carnivores, livestock and humans result in conflict or livestock depredation, the safety of both wildlife and humans are at risk. Reducing livestock depredation by grizzly bears (Ursos arctos) is crucial to the continued recovery of the species. We used 5 years of grizzly bear location data in the Mission Valley, Montana, to analyze habitat selection. Bear use indicated preference to areas in closer proximity to streams and wetlands than to livestock sites. Bears also showed a positive association with the density of homes. Our results showed that livestock were not being selected as a resource by grizzly bears, but also highlighted the importance of protecting livestock near riparian habitats to prevent depredation. These mapping methods can be used to identify how and where electric fencing, bear resistant garbage bins and other conflict mitigation efforts should be focused
Straight From the Horse's Mouth
No full textWhat prompts a private landowner to decide that opening the gate’s for scientists or wildlife managers is a good idea? In this presentation, we will hear from several private landowners in the Bitterroot Valley who embraced research and inventory projects. Why do they participate? What have they learned? How do they see these types of collaborations supporting conservation efforts in the Bitterroot Valley and elsewhere? Please join us in celebrating a few people brave enough to venture to Butte to visit with you. We’ll allow ample time for discussion
Long-Term Band Encounters of Rehabilitated North American Eagles
Get PDFBetween 1973 and 2020, 122 Golden Eagles and 115 Bald Eagles submitted to veterinary medical rehabilitation were banded and released upon recovery in three western states. Adults of both species comprised the most commonly banded age class of rehabilitated (rehab) eagles. Bald Eagles admitted for toxins spent less time in rehabilitation than for those admitted for collision trauma. Encounter (band read for any reason) data from banded eagles provided by the Bird Banding Laboratory (BBL) were analyzed and fitted to appropriate functions in an attempt to describe underlying distributions inherent in the data. Up to March 2020, 28 (12.2%) rehab eagles had been encountered. Encounter rate was 7.4% for rehab Golden Eagles and 16.5% for rehab Bald Eagles, slightly different than those reported by BBL overall (8.0%, 12.2%, respectively). All Golden Eagles were recovered (encountered dead) but 26.3% of Bald Eagles were encountered alive. Days in rehabilitation were not different between species or between Bald Eagles encountered dead or alive. Sex ratio of encountered eagles was not different from ratio of banded eagles of either species. Median time between release and encounter for Golden Eagles was 1.75 yr and 1.42 yr for Bald Eagles. Median distance from banding to encounter site for Golden Eagles was 7.5 km and 115.7 km for Bald Eagles. Number of encounters per year was not related to number of rehab eagles banded that year or for any year previous. Encounters of live Bald Eagles > 30 yr old are discussed. Rehab Golden Eagles may have originated predominantly from western Canada and Alaska while Bald Eagles may have been a mix of a local, non-latitudinal migratory population and seasonal latitudinal migrants. Small sample sizes and lack of precise encounter data prevents utility of rehab eagle encounters to contribute to demographic vital rate estimates needed for effective management of either species. Banding rehab eagles may not justify the manpower investment by BBL required to manage data from banders that band rehab eagles exclusively. Falconry training may be warranted to increase survival potential of rehab Golden Eagles. If recent trends continue, increased rehabilitation effort focused on Golden Eagles may be warranted