Monitoring Responses of Bear Foods to Climate Change Evaluating Adaptive Monitoring Designs for Occupancy Studies

Methods for assessing site occupancy while accounting for imperfect detection have quickly become important for ecologists wishing to study the distribution and prevalence of species across landscapes.  Occupancy data are convenient to collect because, while they do require repeated sampling efforts, they do not require the marking of individual organisms. Some guidance on monitoring for occupancy studies has been provided for conventional settings.  However, coupling the data collection and analysis components via an optimal adaptive sampling design may improve precision of estimates and save money. Optimal adaptive sampling designs have not been applied to occupancy models previously. We present a design criterion that facilitates adaptive monitoring for occupancy studies and illustrate its advantages and disadvantages through the use of simulations and real-data scenarios.  Our findings indicate that, depending on the focus of the study in question, monitoring designs can be improved substantially by considering adaptive sampling schemes

Monitoring Huckleberries for Invasive Fruit Flies and Climate Change Impacts on the Flathead Indian Reservation (Poster)

The huckleberry (Vaccinium spp.) has been important to both bears and the Salish people for hundreds of years. With predicted climate changes including increasing temperature, increasing variability in weather, and unknown changes in precipitation it is important to understand effects on huckleberry plants on the Flathead Reservation. In this project, we are proposing to extend huckleberry phenology research in Glacier National Park led by Dr. Tabitha Graves to the Flathead Reservation. The USGS project aims to understand potential climate change impacts on grizzly bear food sources, a research need identified in a workshop evaluating climate change impacts to grizzly bears (Servheen and Cross 2010).  Two potential impacts include 1) changes in phenology that could impact pollination rates and thus productivity and 2) the possible presence of an invasive fruit fly, the spotted wing drosophila that lays eggs in ripe fruit, and can cause the fruit to drop off early.  I will use remote cameras that record pictures every day to measure the length of time individual flowers bloom and individual berries are present.  This will be used to evaluate how flowering time and duration and ripe berry time and duration varies with temperature across sites that range in precipitation and solar radiation. Productivity metrics will be recorded at the peak of the berry season. All findings and conclusions will be a part of my senior thesis and will be provided to the Confederated Salish and Kootenai Tribes

Inter-Individual Isolation by Distance: Implications for Landscape Genetics

Many approaches to understanding the influence of landscape on gene flow account for isolation by distance, a phenomena where individuals that are closer together are more likely to be more closely related. Most theoretical research has focused on isolation by distance between populations. We simulated the expected isolation by distance patterns between individuals within a finite population and found an asymptotic pattern. New null models are needed in landscape genetic approaches to correctly account for isolation by distance patterns. We will briefly review isolation by distance and discuss the factors (time, variance in dispersal, and mutation rates) influencing isolation by distance patterns. Our results have implications for estimating how difficult it is for animals to move through the landscape

Bighorn Sheep Movements and Mineral Lick Use in Waterton-Glacier International Peace Park (Poster)

This study used bighorn sheep telemetry data collected in Glacier National Park, Waterton Lakes National Park, and the Blackfeet Reservation to examine bighorn sheep movements and use of known mineral licks.  Over 168,400 GPS locations were collected between 2002 and 2011 on 97 bighorn sheep individuals from 17 different social groups.  We examined the proximity of bighorn sheep telemetry data to 32 known mineral lick locations to describe timing and frequency of mineral lick use.  Fifty individuals had locations near known mineral licks, and most mineral lick visits took place between May and August.  We compared movements towards known mineral lick locations with general bighorn sheep movements.  After estimating bighorn sheep kernel home ranges, we evaluated how movement towards the lick, timing, and frequency of use varied depending on location of the lick relative to sheep home ranges.  We conducted a k-means cluster analysis of movement characteristics to identify potential locations of unknown mineral licks and movement pinch points.  We will discuss options for using these locations to monitor bighorn sheep health and population size

Evaluating Reproductive Success and Changes in Genetic Diversity of Grizzly Bears in Northwestern Montana

Current range expansions of large terrestrial carnivores are occurring following anthropogenically-induced range contraction. Contractions are often incomplete, leaving small remnant groups in refugia throughout the former range. We know little about underlying eco-evolutionary processes that influence how remnant groups are affected during range expansion. We used data from a spatially-explicit, long-term genetic sampling effort of grizzly bears (Ursus arctos) in the Northern Continental Divide Ecosystem (NCDE) to identify the processes underlying spatial patterns of genetic diversity. We conducted parentage analysis to evaluate how reproductive success and migration contribute to spatio-temporal patterns of genetic diversity in remnant groups of grizzly bears existing in the southwestern (SW), southeastern (SE), and east-central (EC) regions of the NCDE. Highly skewed reproductive success and local inbreeding caused distinct signatures in remnants that eroded rapidly (~1 generation) during population expansion and migration into the regions. Our results highlight that individual-level genetic and reproductive dynamics play critical roles during genetic assimilation, and show that patterns of genetic distinctiveness on the leading edge of an expansion may result from historical demographic patterns that are highly ephemeral

Counting Bears, P’s And Q’s: An Efficient Sample Design for a Spatial Capture Recapture Hair Snag Study of Grizzly Bears

Accurate assessment of abundance can be expensive and managers often seek to minimize costs. Because spatial capture recapture (SCR) methods explicitly account for variation in trap effort in space and time and permit the use of covariates to explain abundance, substantial flexibility in design and thus reduction in costs may be possible. Estimates of grizzly bear (Usus arctos) densities and abundances in 4 management units in Alberta were very low  (superpopulation n =  47-133) in the latest studies occurring from 2004-2008. Since these first provincial population estimates were obtained, management, landscape, and habitat conditions have changed. Managers would like updated abundance information but also seek to reduce the costs of acquiring these data. We assessed 1) the behavior of SCR models across several general sample designs and 2) whether we could eliminate sampling in helicopter-access-only areas in the Yellowhead management unit while maintaining accurate estimates. We used a combination of retrospective subsampling of existing data from a 2004 sampling effort and simulations to evaluate several designs. Placing sampling arrays in areas with high densities of bears decreased variance, while the fine-scale configuration of traps did not greatly influence estimates. Simulations of designs for Alberta with more intensive sampling of only the areas accessible by road and no sampling of more expensive helicopter-access-only areas provided robust estimates with little loss in precision. We will describe the framework and assumptions of SCR models with covariates for abundance in comparison with traditional capture recapture models

Linking Landscape Characteristics to Local Grizzly Bear Abundance Around Glacier National Park

Grizzly bear (Ursus arctos) habitat use has been extensively studied, but habitat has rarely been linked to demographic parameters and habitat models have not accounted for variation in detection or spatial autocorrelation. We collected bear hair from bear hair traps and rub trees in and around Glacier National Park (GNP) in northwestern Montana and genotyped the samples to identify individuals. We developed a hierarchical model with 1) explicit landscape and habitat variables that we theorized might influence abundance, 2) separate sub-models of detection probability for each sampling type, 3) covariates to explain variation in detection, 4) a conditional autoregressive (CAR) term to account for spatial autocorrelation, and 5) weights to identify most important variables. Road density and percent mesic habitat best explained variation in female grizzly bear abundance and the spatial autocorrelation term was not supported. Female abundance was higher where road density was lower and where more mesic habitat exists. Detection of females increased with rub tree sampling effort. Road density best explained variation in male grizzly bear abundance and the spatial autocorrelation term was supported. More male bears occurred in areas of low road density. Detection of males increased with rub tree and hair trap sampling effort and decreased with time. Our finding that road density influences abundance concurs with conclusions of earlier studies that road density influences habitat use

An Initial Assessment of the Potential of Genomic Analysis to Help Inform Bighorn Sheep Management

Genetic research may be a useful approach for understanding factors that could impact productivity and restoration of bighorn sheep (Ovis canadensis) herds.  For example, genetic consequences of inbreeding in small populations can impact recruitment and local adaptations can influence translocation success.  This modest pilot study quantified genetic attributes of bighorn sheep populations with a range of different herd histories in Montana and Wyoming to investigate genetic similarity and differences, genetic heterogeneity and genetic distance.  Employing an Ovine array containing about 700,000 single nucleotide polymorphisms (SNPs) with approximately 24,000 markers that are informative for Rocky Mountain bighorn sheep, we used whole genome genotyping to analyze genetic material.  This technique represents a significant advancement in genetic analysis of bighorn sheep, as most previous studies have used microsatellites and less than 200 genetic markers.  We analyzed approximately fifteen individuals from each of four different populations that we predicted would differ in genetic characteristics, due to population dissimilarities that potentially impacted their genetics, including origin (native/reintroduced), population size, bottleneck history, degree of connectivity, and augmentation history.  We selected four populations that provided a spectrum of these herd attributes, including the Tendoys, Stillwater and Glacier National Park in Montana and the northeastern Greater Yellowstone Area in Wyoming.  We present the results of this effort and examine expected and observed heterogeneity and genetic distance estimates to evaluate the potential for links between genetics and herd demography.  We discuss the utility of genetic analyses in improving knowledge of bighorn sheep populations and potential implications for bighorn sheep management