USGS field technician photographing bumble bees captured during monitoring surveys at Logan Pass, Glacier National Park, Montana.
Tabitha Graves, Ph.D.
I answer applied research questions at the intersection of wildlife biology, landscape ecology, and statistics.
Research Interests
My work falls under three broad themes: (1) understand the influence of humans and associated land use impacts on wildlife distributions, densities, and related processes at local and landscape scales, (2) develop new analytical tools that address the influence of landscape features on animals at the sub-population and population scales, and (3) improve efficiency of research and monitoring through optimal study design. I have >15 years experience studying grizzly bears, bighorn sheep, elk, and the development of novel and integrated analyses of habitat use, connectivity, migration, and genetics, all very applied work. I have also assisted with projects studying black bears, wolverines, mountain goats, wolves, lynx, kinkajou, loons, hawks, owls, riparian vegetation, pika, and sugar pine.
Current projects
- Chronic wasting disease- evaluating changes in density and contacts across multiple cervid populations
- Assessing current and changing forage for elk and mule deer with climate change
- Assessing connectivity and migration in and around Glacier National Park (GNP)
- Optimal monitoring of wildlife with occupancy models
- Pollinator communities and Western bumble bee assessment on BLM lands in Montana and the Dakotas, in GNP, and across the west
- Mountain goat and bighorn sheep abundance, trend, population structure, and habitat
- Spatial capture recapture approaches
- Water to Wildlife: Connecting changes in water to vegetation to wildlife across 3 northwest parks
- Evaluating potential impacts of climate change on berry plant abundance and production
Professional Experience
Research Ecologist, USGS Northern Rocky Mountain Science Center: 2/10/14-present
David H. Smith Post-doctoral Conservation Research Fellow: 7/12 – 2/14
Education and Certifications
PhD. 2012. Northern Arizona University. Dissertation Title: Spatial ecology of grizzly bears in northwestern Montana and estimating resistance to gene flow
M.S. Wildlife Biology. 2002. University of Montana
Honors B.A. German Literature with distinction. 1995. University of Wisconsin-Madison
Science and Products
Bighorn Sheep and Mountain Goat Research in Western National Park Units
Using Pollinator Environmental DNA to Assess the Ecological Resilience of America’s Grasslands
From Water to Wildlife: Linking Water Timing and Availability to Meadows and Wildlife in a Changing Climate
Developing Tools to Evaluate Chronic Wasting Disease Transmission Risk
USGS Chronic Wasting Disease Research at NOROCK
Western Bumble Bee and Native Pollinator Research
Predicting Future Forage Conditions for Elk and Mule Deer in Montana and Wyoming
NOROCK Large Carnivore Research Program
Science in Glacier National Park
Long Term Research in northwest Montana
Grizzly Bear Family Tree
Grizzly Bear Dispersal
Desert bighorn sheep (Ovis canadensis nelsoni) datasets from Grand Canyon National Park, 2010-2016
Bumble bees and flowering plants in Glacier National Park 2023
Black bear (Ursus Americanus) spatial capture recapture dataset in and near Glacier National Park, Montana, USA, 2004
Glacier Waterton International Peace Park bighorn sheep (Ovis canadensis) habitat selection, 2002-2012
Glacier Waterton International Peace Park bighorn sheep (Ovis canadensis), 2002-2012
Age ratios and landscape change covariates for mule deer (Odocoileus hemionus) herd units in Wyoming, USA, 1985-2019
Downscaled western bumble bee predicted occupancy for 2020, western conterminous United States.
Occurrence data of the western bumble bee from 1998 to 2020 across the western United States
Wyoming statewide time-stamped oil and gas activity, 1900-2020
Bumblebee Surveys in Montana, North Dakota, South Dakota, and Nevada, USA (ver. 2.0, April 2023)
Neonicotinoid nitroguanidine group insecticide application rates estimated across the western conterminous United States, 2008 to 2014
Western bumble bee predicted occupancy (1998, 2020) and future projections (2050s), western conterminous United States
USGS field technician photographing bumble bees captured during monitoring surveys at Logan Pass, Glacier National Park, Montana.
Many bumble bee species have declined in recent decades due to changes in habitat, climate, and pressures from pathogens, pesticides and introduced species. The western bumble bee, once common throughout western North America, is a species of concern and is being considered for listing by the U.S. Fish and Wildlife Service under the Endangered Species Act.
Many bumble bee species have declined in recent decades due to changes in habitat, climate, and pressures from pathogens, pesticides and introduced species. The western bumble bee, once common throughout western North America, is a species of concern and is being considered for listing by the U.S. Fish and Wildlife Service under the Endangered Species Act.
The USGS studies bighorn sheep movements, population structures, and habitat use in and near Glacier National Park.
The USGS studies bighorn sheep movements, population structures, and habitat use in and near Glacier National Park.
Population and spatial dynamics of desert bighorn sheep in Grand Canyon during an outbreak of respiratory pneumonia
Evaluating density-weighted connectivity of black bears (Ursus americanus) in Glacier National Park with spatial capture–recapture models
Quantifying effectiveness and best practices for bumblebee identification from photographs
Bighorn sheep associations: Understanding tradeoffs of sociality and implications for disease transmission
Ecological significance of Wild Huckleberries (Vaccinium membranaceum)
Recent and future declines of a historically widespread pollinator linked to climate, land cover, and pesticides
The acute decline in global biodiversity includes not only the loss of rare species, but also the rapid collapse of common species across many different taxa. The loss of pollinating insects is of particular concern because of the ecological and economic values these species provide. The western bumble bee (Bombus occidentalis) was once common in western North America, but this species has become
Final Report: Predicting impacts to mule deer of changing forage using landscape surface phenology metrics
Precision and bias of spatial capture–recapture estimates: A multi-site, multi-year Utah black bear case study
Eyes on the herd: Quantifying ungulate density from satellite, unmanned aerial systems, and GPScollar data
Average kinship within bighorn sheep populations is associated with connectivity, augmentation, and bottlenecks
Genetic attributes and research interests
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
WildAgg: an R package to estimate and visualize wildlife aggregation data
Science and Products
Bighorn Sheep and Mountain Goat Research in Western National Park Units
Using Pollinator Environmental DNA to Assess the Ecological Resilience of America’s Grasslands
From Water to Wildlife: Linking Water Timing and Availability to Meadows and Wildlife in a Changing Climate
Developing Tools to Evaluate Chronic Wasting Disease Transmission Risk
USGS Chronic Wasting Disease Research at NOROCK
Western Bumble Bee and Native Pollinator Research
Predicting Future Forage Conditions for Elk and Mule Deer in Montana and Wyoming
NOROCK Large Carnivore Research Program
Science in Glacier National Park
Long Term Research in northwest Montana
Grizzly Bear Family Tree
Grizzly Bear Dispersal
Desert bighorn sheep (Ovis canadensis nelsoni) datasets from Grand Canyon National Park, 2010-2016
Bumble bees and flowering plants in Glacier National Park 2023
Black bear (Ursus Americanus) spatial capture recapture dataset in and near Glacier National Park, Montana, USA, 2004
Glacier Waterton International Peace Park bighorn sheep (Ovis canadensis) habitat selection, 2002-2012
Glacier Waterton International Peace Park bighorn sheep (Ovis canadensis), 2002-2012
Age ratios and landscape change covariates for mule deer (Odocoileus hemionus) herd units in Wyoming, USA, 1985-2019
Downscaled western bumble bee predicted occupancy for 2020, western conterminous United States.
Occurrence data of the western bumble bee from 1998 to 2020 across the western United States
Wyoming statewide time-stamped oil and gas activity, 1900-2020
Bumblebee Surveys in Montana, North Dakota, South Dakota, and Nevada, USA (ver. 2.0, April 2023)
Neonicotinoid nitroguanidine group insecticide application rates estimated across the western conterminous United States, 2008 to 2014
Western bumble bee predicted occupancy (1998, 2020) and future projections (2050s), western conterminous United States
USGS field technician photographing bumble bees captured during monitoring surveys at Logan Pass, Glacier National Park, Montana.
USGS field technician photographing bumble bees captured during monitoring surveys at Logan Pass, Glacier National Park, Montana.
Many bumble bee species have declined in recent decades due to changes in habitat, climate, and pressures from pathogens, pesticides and introduced species. The western bumble bee, once common throughout western North America, is a species of concern and is being considered for listing by the U.S. Fish and Wildlife Service under the Endangered Species Act.
Many bumble bee species have declined in recent decades due to changes in habitat, climate, and pressures from pathogens, pesticides and introduced species. The western bumble bee, once common throughout western North America, is a species of concern and is being considered for listing by the U.S. Fish and Wildlife Service under the Endangered Species Act.
The USGS studies bighorn sheep movements, population structures, and habitat use in and near Glacier National Park.
The USGS studies bighorn sheep movements, population structures, and habitat use in and near Glacier National Park.
Population and spatial dynamics of desert bighorn sheep in Grand Canyon during an outbreak of respiratory pneumonia
Evaluating density-weighted connectivity of black bears (Ursus americanus) in Glacier National Park with spatial capture–recapture models
Quantifying effectiveness and best practices for bumblebee identification from photographs
Bighorn sheep associations: Understanding tradeoffs of sociality and implications for disease transmission
Ecological significance of Wild Huckleberries (Vaccinium membranaceum)
Recent and future declines of a historically widespread pollinator linked to climate, land cover, and pesticides
The acute decline in global biodiversity includes not only the loss of rare species, but also the rapid collapse of common species across many different taxa. The loss of pollinating insects is of particular concern because of the ecological and economic values these species provide. The western bumble bee (Bombus occidentalis) was once common in western North America, but this species has become
Final Report: Predicting impacts to mule deer of changing forage using landscape surface phenology metrics
Precision and bias of spatial capture–recapture estimates: A multi-site, multi-year Utah black bear case study
Eyes on the herd: Quantifying ungulate density from satellite, unmanned aerial systems, and GPScollar data
Average kinship within bighorn sheep populations is associated with connectivity, augmentation, and bottlenecks
Genetic attributes and research interests
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.