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Responses of Elk to Changes in Travel and Access Management
No full textRifle-hunting on land accessible to the public is the main tool wildlife managers use to manage the abundance of elk (Cervus canadensis) in the western United States. Elk are increasingly located on land inaccessible to hunters during rifle season in the western United States, decreasing the ability of managers to reduce the abundance of elk and harvest opportunity for hunters. Management actions are used to balance hunting risk across landscapes and assumed to influence the behavior of elk, but evidence is limited. We evaluated how restricting hunter access and motorized routes influenced the behavior of elk during rifle season in the northern Sapphire Mountains, Montana, USA. We used locations of female and male elk during the rifle season during 2014-2015 prior to restrictions and again in 2019-2020 following restrictions to evaluate elk responses. We hypothesized restrictions would influence the behavior of elk more strongly than other factors since elk have been shown to respond strongly to changes in hunting risk. Additionally, we evaluated how access of elk to hunters during rifle season changed over time to understand patterns in the location of elk. We found no support that elk responded to restrictions. Preexisting use of adjacent land by elk and restrictions mainly to motorcycles likely decreased efficacy of restrictions. Further, access of elk to hunters was low, and decreased over time for male elk
Identification of Bumblebee Species from Photographs Taken in the Field: Quantifying Effectiveness and Best Practices
No full textWith many bumblebee (Bombus) species in decline across North America, there is an urgent need to collect data on the status of bumblebees in Montana; however, bumblebee identification requires specialized expertise and can be difficult in the field. Traditionally, bumblebee specimens have been collected and pinned for experts to view and identify. However, storing and managing specimens presents logistical challenges. In addition, three bumblebee species in Montana are under consideration for listing which may lead to restrictions on lethal sampling. Taking photographs of bumblebees in the field offers a non-lethal alternative that may be more cost-effective, appropriate for species of concern, or suitable for engaging community scientists. We seek to evaluate the effectiveness of identifying bumblebee species in Montana from photographs. In collaboration with BLM Montana/Dakotas, we took photographs and collected specimens of >565 bumblebees between 2018 and 2021. The species of each bumblebee was determined separately from specimens by Montana bumblebee expert Amy Dolan and from photographs by bumblebee expert Rich Hatfield. We will use these data to answer: (1) How frequently were species identified from photographs of bumblebees, and how frequently did these identifications agree with specimen identifications? (2) What methods and practices contribute to successful bumblebee identification from photographs? (3) Are there specific species or castes that cannot be reliably identified to species level from photos? Our goal is to inform viable and efficient methods for sampling and identifying bumblebee species, including species of concern, across Montana and beyond
Montana Chronic Wasting Disease Surveillance and Monitoring - 2021 Season Review
No full textMontana, Fish, Wildlife, and Parks (FWP) has been conducting surveillance for Chronic Wasting Disease (CWD) since 1998, and first detected CWD in wild deer in 2017. In 2021, FWP prioritized sampling in northwestern, southwestern, south central, and east central Montana. Additionally, FWP continued to target sampling in the Libby CWD Management Zone and conducted a Southwest Montana CWD Management Hunt for a 2nd consecutive year. Surveillance and management efforts focused on maximizing the detection of CWD in new areas, limiting the spread of CWD, maintaining or reducing prevalence of CWD in endemic areas, improving CWD communication and outreach with the public, and providing hunters the opportunity to have their harvested animal tested for CWD. During the 2021 season, FWP tested 8,525 samples from mule deer (n=3,532), white-tailed deer (n=3,991), elk (n=951), and moose (n=51). Of these, 323 animals tested positive and CWD was detected in 4 new hunting districts (317, 330, 340, and 700). Among positive hunting districts, prevalence estimates between 2017-2021 ranged from Between 2017–2021, CWD prevalence was 6% (95%.CI:.5-7%) in white-tailed deer within the Libby CWD Management Zone and 21% (95% CI:19-23) in white-tailed deer within the Southwest Montana CWD Management Hunt Area. For 2022, FWP will continue to promote proper carcass disposal and transport regulations and advocate sample collection by hunters. Additionally, CWD management actions will be evaluated for addressing high CWD prevalence areas across the state
Assessing the Effectiveness of Autonomous Recording Unit Surveys for Detection of Great Gray Owls in Western Montana
No full textMontana has classified the Great Gray Owl as a Species of Greatest Conservation Need (SGCN3) and a Species of Greatest Inventory Need (SGIN). Montana non-game species listed as SGIN are not sufficiently monitored by standard ecological monitoring programs, typically because they are cryptic and difficult to detect. We have completed three years of surveys in high quality habitat utilizing Autonomous Recording Units (ARU) and traditional Callback Surveys to assess occupancy of this elusive species. A total of 101 cells in western Montana have been surveyed with ARU detectors, including 30 sites with two detectors deployed simultaneously. Great Gray Owls were detected in 8 of the 101 survey cells. We’ll present findings on the effectiveness of ARU surveys for the detection of cryptic owl species, as well as information about the detection of non-target species of information need, and best practices for ARU surveys of owls
Searching for The Horny Toad - Trials and Tribulations to Document Greater Short-Horned Lizards in Montana
No full textGreater short-horned lizards (GSHL) are a fascinating and cryptic lizard that are poorly documented in Montana. In the State Wildlife Action Plan, they are identified as a Species of Greatest Conservation Need (SGCN3) and a Species of Greatest Inventory Need (SGIN). With recent declines in reptile populations globally, it is important to establish baseline information about occurrence and a way to monitor population trends in the state. We developed a model to identify suitable habitat based on previous studies, existing observations, and expert opinion. We used standard methods for amphibian and reptile visual encounter surveys (ARVES) with sites randomly sampled within suitable habitat across the GSHL range as defined by the Montana Natural Heritage Program. We sampled 70 sites and observed 18 GSHL from 2016 to 2019 at 6 sites. Our efforts did not produce enough detections to support site occupancy analyses nor examination of variables that affect occupancy or detection probability. We are currently refining our habitat model and adapting our survey protocol based on recent studies and conversations with herpetology specialists to increase detections. In addition to standardized surveys, we also used outreach to request incidental observations from the public. These efforts produced more than 100 additional observations and have proven quite valuable in understanding range and habitat used by GSHL. We will continue to solicit help from the public and ask that if YOU encounter a GSHL, please help us out and let us know
Effects of Survey Conditions on Dusky Grouse Counts in Montana
No full textDusky grouse (Dendragapus obscurus) are a species of upland game bird for which monitoring methods are still being developed. Understanding factors that influence the detections of grouse is crucial for developing survey protocols that maximize observability of grouse and provide unbiased estimates of population size and trends. Our objective was to explore relationships between grouse counts and survey conditions to inform future statewide survey protocols. We conducted multiple 4-minute point counts during the spring mating season from late April–early June 2020. We explored the effect of wind speed, temperature, cloud cover, precipitation, minutes since sunrise, and date on the maximum number of dusky grouse counted at each site using generalized linear models and information theory. The number of grouse observed declined with wind speed (? = -0.06 ± 0.04SE), and increased with ambient temperature (? = 0.02 ± 0.01SE). The number of grouse counted for date and minutes since sunrise had a positive quadratic relationship, with peak counts occurring from May 5 th – May 20 th , and between 100- 150 minutes post sunrise. Higher counts were observed when cloud cover was low, and snow had the strongest negative impact compared to other forms of precipitation. These results provide valuable insight for identifying favorable conditions for surveying dusky grouse, which could lead to effective management decisions for this species
Greater Sage Grouse Chick Survival as a Function of Grazing Management, Morphometric and Habitat Variables in Central Montana
No full textChick survival is the lowest and most variable vital rate for grouse, but it is important because surviving individuals contribute to the breeding population each year. We estimated the effects of grazing, morphometric, and habitat variables on chick survival in a greater sage-grouse population in central Montana where the Natural Resources Conservation Service and landowners implemented Sage-Grouse Initiative (SGI) rotational grazing systems during 2011-2019. We used a Kaplan-Meier survival function with staggered entry and right-censoring to evaluate chick survival, log-rank models to test for differences among categorical variables, and Cox proportional hazards models to evaluate chick mortality risk as function of time-dependent and continuous variables. Annual survival estimates for 521 chicks were highly variable (range: 0.19-0.60) and differed significantly among years. Median survival time was 42 d (95% CI=33-59 d, all years pooled). Male chicks had substantially higher survival risk than females, and there was some evidence for a higher mortality risk associated with use of SGI pastures during and post enrollment, though we had low sample sizes in pre-SGI categories. Our results suggest SGI grazing management did not benefit chick survival, and that annual effects and sex of chicks were important. Managers might expect female-biased survival and fewer males displaying on leks in the spring following a year with disturbances that affect chick survival
Associations Between Public Lands Cattle Grazing and Long-term Trends in Vegetation
No full textCattle grazing is a common practice on public lands in the western United States; however, it is largely unknown how cattle grazing on public lands has affected rangelands. Thus, our primary objective was to identify whether grazing practices were associated with changes in herbaceous vegetation productivity on public lands. To address this objective, we acquired billed Animal Unit Month (AUM) data and above-ground herbaceous biomass data for 12,628 Bureau of Land Management BLM grazing allotments for the past 36 years. We fit linear mixed effects models with annual change and 36-year trends in vegetation biomass as response variables, and grazing intensity (AUM/ha), precipitation, and temperature as predictor variables. Trends in precipitation and temperature had the strongest effects on trends in perennial and annual herbaceous biomass, with allotments that got warmer and drier over time having the largest decreases in biomass. Grazing intensity had weak to no associations with trends in herbaceous biomass. Our results suggest that current cattle grazing practices on BLM allotments were not strongly associated with vegetation productivity for the past 36 years, when considering allotment-scale effects across the range
Effects of Climate on Western Bumble Bee Declines in North America Now and in the Future
No full textThe Western bumble bee (Bombus occidentalis), once common throughout Western North America is under consideration for listing by the U.S. Fish and Wildlife Service (USFWS). To support the USFWS Species Status Assessment of the Western bumble bee we assessed the relative influence of climate, landcover, and pesticides on the trends in occupancy for the Western bumble bee across its range in the conterminous United States. We used a Bayesian hierarchal occupancy model leveraging 14,457 surveys conducted over 23 years (1998-2020). We found strong support for a negative relationship between occupancy and two climate components: temperature during the warmest quarter and cumulative years of drought. We also found a complex relationship between the presence of Western bumble bee and landcover types with the species being more common in areas of increased forest and shrub cover. These relationships are non-linear and suggest forest/non-forest edge is an important habitat characteristic. We found variable declines in ecoregions across the species range from moderate declines in the Greater Yellowstone Ecosystem (-15%) to much steeper declines in the Cascades-Sierra Nevada-Coastal forests of the western US (-62% to -75%). In Montana, predicted declines are largest in the semi-arid prairies of the Eastern portion of the state (-53%) but still evident in the mountainous Western portion (-37%). We also used a range of future scenarios (based on 4 climate models, 2 emission scenarios, and 3 landcover forecasts) to project occupancy (2050’s) and found continued range-wide declines even under the most conservative scenarios
A Preliminary Look at The Effects of Livestock Grazing on Greater Sage Grouse Nest Success and Hen Survival in Central Montana
No full textLivestock grazing is a dominant land use in sagebrush habitat, leading to ongoing questions about the relationships between grazing and coexisting wildlife populations. We investigated the effects of livestock grazing on greater sage grouse demographic rates. This work is based on a decade-long collaboration among multiple agencies and private landowners in central Montana. We evaluated whether rotational grazing systems implemented through the Sage Grouse Initiative (SGI) in central Montana can be used to effectively manage sage grouse habitat to support different vital rates. We collected data on livestock grazing and sage grouse demographic rates from 2011-2020. First, we synthesized grazing data in several different ways to investigate both short- and long-term effects of SGI grazing systems on demographic rates. Second, we explored the influence of the different grazing systems on sage grouse nest success and hen survival. Preliminary results suggest that inter-annual variation has a stronger effect on both demographic rates than grazing management. In our ongoing work, we will expand our current preliminary models by adding additional habitat and weather variables. Ultimately, our findings will help inform grazing management to support sage grouse in central Montana