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Reintroducing Sharp‐Tailed Grouse to Western Montana ‐ First Year of Translocations
No full textSharp‐tailed grouse (Tympanuchus phasianellus) historically occupied intermountain Grasslands west of the Continental Divide in Montana but were likely extirpated by the early 2000s. Montana Fish, Wildlife and Parks recently began efforts to reintroduce sharp‐tailed grouse to two sites in western Montana. For prairie grouse, translocation failure rates are high, so monitoring is essential to evaluate translocation success and inform future reintroduction efforts. We monitored the dispersal movements and demography of sharp‐tailed grouse captured in east‐central Montana and translocated to the Blackfoot and Bitterroot Valleys in April – May 2023. We tracked 75 female grouse fitted with GPS‐PTT (25 grouse), VHF (26), or Motus transmitters (24) and monitored 20 nesting attempts and 9 broods. Some PTT‐tagged females made long exploratory movements following release, traveling up to 75 km from the release site. However, many birds remained within 1–5 km of the release sites or moved to properties 11–17 km from the release sites where new leks had been established. Survival was relatively low following translocation, and 100‐d post‐release survival was 0.28 (95% C.I.: 0.18 - 0.44). Survival increased following this initial period, and 200‐d post‐release survival was 0.22 (0.13 - 0.39). The nest initiation rate was high for surviving birds (0.75 for PTTtagged females), and nests were often located near newly established lek sites. Apparent nest survival (0.45) and brood survival (0.56) were similar to resident populations of sharp‐tailed grouse. Translocations and monitoring will continue through 2026, and our results will inform ongoing sharptailed grouse reintroduction efforts in western Montana
Effects of Timber Harvest and Wildfire Disturbance on Grizzly Bear Space Use in the Northern Continental Divide Ecosystem
No full textTimber harvest and wildfire disturbance can have long‐term effects on wildlife habitat. Studies have demonstrated both positive and negative effects of forest disturbance on grizzly bears. Balancing grizzly bear conservation and managing forest disturbances is a complex and dynamic challenge for land managers. Research on the effects of timber harvest and wildfire disturbance on grizzly bears can aid in developing strategies that balance species conservation and forest management objectives. Using GPS data from grizzly bears in Montana’s Northern Continental Divide Ecosystem (NCDE), we aim to understand how grizzly bears respond to forest disturbance. We hypothesize that grizzly bears use forest disturbance but that factors such as access to foods, security, and cover influence grizzly bear space use in and around disturbance patches. Our long‐term dataset (24 years) for collared grizzly bears and the NCDE’s detailed records of timber harvests and wildfires provide a unique opportunity to study these effects for a range of disturbance conditions
Evaluating Community Assembly using Species Niche Strategies Within a Multispecies Occupancy Modeling Framework
No full textIdentifying species according to the type and flexibility of their niche strategies may afford ecologists a way to predict how species are structured within their communities. Small mammal communities offer an ideal study system to test relationships between species niche strategies and bottom up (habitat) influences on assembly. Most North American small mammals belong to a single species‐rich taxonomic order (Rodentia), with a wide range of physiological and behavioral adaptations to various terrestrial environments. They often occur in multi‐species communities where both interspecific competition and resource limitations may influence occupancy and abundance. The transition from the short‐ and mixed‐grass prairie (High and Northwest Great Plains) to the sagebrush steppe (Wyoming and Great Basins) supports a gradient of abiotic and biotic conditions that facilitate the establishment of variable small mammal communities. Using multispecies occupancy models we evaluated the impact the grasslandsagebrush gradient and species niche strategies have on species richness and community assembly. Species richness is an essential measurement of biodiversity and vital towards evaluating community health with species declining globally. Using a combination of bottom up and species biological strategies within a framework that requires only presence/absence for species can be an advantageous method for monitoring ecosystem health and community persistence
Evaluation of Sex and Age Identification Characteristics in Sharp-tailed Grouse (Poster)
No full textSharp‐tailed Grouse are a popular upland game bird for sportsman and a species with a long history of population reintroductions and augmentations. Center rectrices have been used as a dominant sex identifier for Sharp‐tailed Grouse with an accuracy rate of 85% to 93%. When managing small populations or reintroduction efforts for a species, error rates as small as 7% could still have significant consequences when calculating population parameters. Often sex and age characteristics are reevaluated for a species, or experts are tested on this knowledge for accuracy. Our objectives are (1) to evaluate the specific measurements or characteristics present to determine sex and age in Sharp‐tailed Grouse and (2) to develop a more detailed key to aid in effective management and monitoring of Sharp‐tailed Grouse populations. To evaluate these characteristics, we will test wildlife professionals at the Montana Chapter Annual Conference on sex and age of Sharp‐tailed Grouse using harvested feathers and wings. Identification data from professionals will be compared against genetic results of the grouse samples. Following the comparative analysis, feather characteristics will be evaluated and an identification key will be developed and tested on a group of non‐experts. Creating thorough tools towards proper sex criteria will strengthen adaptive management for Sharp‐tailed Grouse in the future
Examining Influences on Capture Probability of Migrating Raptors (Poster)
No full textThroughout North America, researchers operate annual fall trapping stations to assess patterns, health, and quantities of migrating diurnal raptors. In Montana, Raptor View Research Institute has been trapping diurnal raptors during fall migration along Montana’s Continental Divide since 2004. While we observe over 1,000 raptors migrating each fall, we typically only capture around 150 individuals per season. Examining factors that determine our trapping success would not only provide us with a greater knowledge of these sensitive apex predators but also increase our capture yield. We investigate a variety of temporal, environmental, and species specific variables to determine what factors influence capture probability, including time of year, weather and the age and sex of individual raptors. We share our findings for some of our most frequently caught species, including Golden Eagles, Red‐tailed Hawks, Coopers Hawks, and Sharp‐shinned Hawks, and offer insight into factors that could affect capture rates at migration stations
Impact of the Presence of Pseudogymnoascus Destructans on Activity of Montana’s Bat Species
No full textIn 2019 the pathogenic fungus Pseudogymnoascus destructans (Pd) which causes the disease White‐Nose Syndrome (WNS) was first detected in Montana. In 2020 Montana began surveys following guidance from the North American Bat Monitoring Program (NABat) to determine the status and inform management of bat species within the state. This effort uses acoustic recording units to record echolocation calls of bats at up to four sites within 10 by 10 km cells. Over the past four years, partners have surveyed 1476 sites within 122 cells. Over 3 million calls have been recorded representing 13 of Montana’s 15 species. Making inference about the trend of WNS impacted species using counts of recorded calls is difficult as calls may represent one or many bats. The large amount of data increases reliance on identifications suggested by the classification software but similarity between calls made by different species can reduce confidence in the suggested species. To address these challenges and minimize risk of misclassification we used a thresholding approach based on characteristic frequency to identify calls made by WNS susceptible species. These calls were then used as a response variable in a Bayesian, hierarchical, spatially misaligned regression model that included environmental and geographics factors as covariates, and allowed for estimation of the impact of fungus presence on the log‐mean bat relative activity. Our results indicate that fewer calls from WNS species are recorded in areas where Pd has been detected, confirming that despite differences in overwintering ecology of bats within the West, declines are likely
The Little Belt Mountains Wild Sheep Restoration Effort
No full textMontana’s Bighorn Sheep Conservation Strategy, published in 2010, calls for Montana Fish, Wildlife & Parks (MFWP) to establish “new viable and huntable populations [of bighorn Sheep”. In 2020, MFWP began one of the first restoration efforts in over 20 years in the Little Belt Mountains of central Montana in partnership with numerous organizations, local landowners, the Wild Sheep Foundation, and the Montana Woolgrower’s Association. In Decembers 2020 and 2021, FWP captured 49 and 33 bighorn sheep, respectively (8 rams, 74 ewes), from the Missouri River Breaks sheep herd and released them in the eastern Little Belts. All 82 sheep were fitted with GPS collars to collect locations every 13 hours, while providing mortality notifications as well as a geo‐fence to help detect comingling with domestic sheep. With extensive monitoring, we documented lamb production in 2021 and 2022. During the first year, we documented 20 mortalities (15 caused by mountain lion) and between the second release and April 2022, an additional 7 ewes were killed by mountain lions—most from the second (or newer), ‘naïve’ cohort. In spring 2022, we documented several sheep sick with or that had died from pneumonia. Having collars on all adult animals in the population provided a unique opportunity to monitor and track the outbreak and mortalities as they occurred. Sixteen sheep succumbed to pneumonia or predation (while symptomatic) since April 2022, along with 16 other (mostly predation) mortalities. However, observations of previously sick animals suggest some may have recovered. To date, 13 collared sheep (including one ram) and at least eight uncollared sheep (lambs born in 2021, 2022, and 2023) are still alive. We will continue to monitor surviving sheep for symptoms and determine next steps in the coming year
Breeding Biology and Migration Ecology of Turkey Vultures in Western Montana
No full textIn recent decades, Turkey Vulture (Cathartes aura) populations have both increased and expanded northward in western North America. At our annual fall migration count site in the Bitterroot Valley of western Montana, the number of vultures seen per 100 observation hours more than tripled from an average of 174 birds in the first four years of the count (2011 to 2014) to 581 birds in the last four years (2019 to 2022). Given their recent population growth and expansion in the west, coupled with knowledge gaps in Turkey Vulture breeding biology and migration ecology, we outfitted more than 50 birds with GPS transmitters over the last five years to better understand the western subspecies of Turkey Vulture (C. a. meridionalis). We discuss our early findings from this project, including the timing, distance, and fidelity of migration routes and the difficulty in identifying and locating breeding individuals. We also touch on ecotoxicology and sources of mortality, including the second documented case of a Golden Eagle predating a Turkey Vulture
Swift Fox Census Survey in Northeast Montana
No full textSwift foxes (Vulpes velox) were surveyed across an area of 11,420 km2 on the prairies of northeast Montana from October 2022 – March 2023. The purpose of this survey was to determine changes in relative distribution, estimate population within the census area, and compare those results to previous census findings. Live trapping and remote camera methods were used to collect data in the field. Surveys were conducted in 74 townships across the census area. Township occupancy analyses were used for camera data and live trap data were analyzed using mark‐recapture estimation. Live traps detected swift foxes at 36 of 45 townships, which resulted in 146 captures of 91 unique individuals. Camera traps detected swift foxes in 16 out of 29 townships, which resulted in 47 visits. Incidental canid observations during the survey period yielded 35 coyotes, 30 red foxes, and 109 swift foxes. It was not possible to identify individuals from camera traps or incidental observations, so some visits could be the same individual. Preliminary results for relative distribution show a slight western expansion within the census area. Comparing live trap results to previous census surveys we see a significantly higher catch per unit effort in 2022 than in 2014, 2005, and 2000. Theseresults indicate a potential increase in the northeast Montana population of swift fox. Recent swift fox reintroductions bordering the census area could be a source of inflation in the population estimate. A comprehensive population survey will be conducted in Canada and Montana in upcoming years
Amphibian Larva Occupancy of Inland Northwest Wetlands ‐ Threat of Non‐Native Fish
No full textAmphibians are the most endangered vertebrate taxa globally. Amphibian conservation and management strategies will benefit from understanding ecological and environmental variables that predict occupancy. We studied amphibian larvae occupancy in four ecoregions along a gradient extending from the Northern Rockies of western Montana to central Washington’s Columbia River Basin. We used classification and boosted regression trees to evaluate the performance of 32 environmental variables in ecological models predicting occupancy of over 7000 amphibian larvae of 6 of the 10 species captured in 106 wetlands. We found that classification trees and boosted regression trees used 3‐5 variables to correctly predict amphibian larvae occupancy in wetlands with relatively high accuracy (i.e., 62‐99% correct classifications) for Long‐toed Salamander (Ambystoma macrodactylum), Pacific Chorus Frog (Pseudacris regilla), Columbia Spotted Frog (Rana luteiventris), Barred Tiger Salamander (Ambystoma tigrinum mavortium), Northern Leopard Frog (Rana pipiens), and American Bullfrog (Lithobates catesbeianus). Qualitative models were used to describe the occurrence of the Sierra Chorus Frog (Pseudacris sierra), Western Toad (Anaxyrus boreas), Great Basin Spadefoot Toad (Spea intermontane), and Rough‐skinned Newt (Taricha granulosa) due to their limited detection in our study. Occupancy of amphibian species varied among the species but often included landscape variables such as proximity to grasslands, forested or woodland areas, streams, and species assemblage. Across three of the four ecoregions, native amphibian occupancy was negatively associated with the presence of non‐native fish. Our results suggest that nonnative fish may depress native amphibian populations in inland northwest lentic wetlands