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Tabitha A Graves

Research Ecologist

Northern Rocky Mountain Science Center

Office Phone: 406-888-7994
Fax: 406-888-5835
ORCID: 0000-0001-5145-2400

USGS Building
Park Headquarters
West Glacier , MT 59936-0128

Supervisor: Claudia E Regan
Vegetation phenology and productivity play a crucial role in surface energy balance, plant and animal distribution, and animal movement and habitat use and can be measured with remote sensing metrics including start of season (SOS), peak instantaneous rate of green-up date (PIRGd), peak of season (POS), end of season (EOS), and integrated vegetation indices. However, for most metrics, we do not yet understand the agreement of remotely sensed data products with near-surface observations. We also need summaries of changes over time, spatial distribution, variability, and consistency in remote sensing dataset metrics for vegetation timing and quality. We compare metrics from 10 leading remote sensing datasets against...
Categories: Publication; Types: Citation
ScienceCache is a scientific geocaching mobile application framework that targets two user groups for citizen science data collection: youth and geocachers. By melding training and games into the hunt for place-based data collection sites and incorporating photo uploads as data and authentication, new volunteers can collaborate in robust data collection. Scientists build a project on the administrative Web site app, specifying locations or goals for new data collection sites, clues for established sites, questions to answer, measurements, or other activities for the site based on their individual data needs. The project builds on the success of the USA National Phenology Network (NPN) and the ScienceBase project...
Wildlife aggregation patterns can influence disease transmission. However, limited research evaluates the influence of anthropogenic and natural factors on aggregation. Many managers would like to reduce wildlife contact rates, driven by aggregation, to limit disease transmission. We develop a novel analytical framework to quantify how management activities such as supplemental feeding and hunting versus weather drive contact rates while accounting for correlated contacts. We apply the framework to the National Elk Refuge (NER), Wyoming, USA, where the probable arrival of chronic wasting disease (CWD) has magnified concerns. We used a daily proximity index to measure contact rates among 68 global positioning system...
Categories: Publication; Types: Citation
This is the data archive for the publication Ungulate Migrations of the Western United States, Volume 1 (Kauffman et al. 2020) and includes the collection of GIS map files that are mapped and described in the report. These map files are meant to provide a common spatial representation of the mapped migrations. This data release provides the means for ungulate migrations to be mapped and planned for across a wide variety of landscapes where they occur. Due to data sharing constraints of participating agencies, not all the files that underlie the mapped migrations included in the report have been released. Data can be viewed at: Data in this archive can be downloaded two ways. To download...
These data represent occupancy estimates for western bumble bee across the western continental United States and the spatial variation in detection probabilities that occur during bumble bee surveys. This product contains five raster layers (appearing as separate bands in a multi-band raster). The first two bands represent the predicted occupancy of western bumble bee in 1998 and 2018. We modeled western bumble bee occupancy as a function of: latitude, longitude, elevation, year, and land cover. The last three bands represent the spatial variation in detection probabilities predicted to occur for surveys conducted across the western United States on three dates (May 15, July 15, and September 15). We modeled detection...
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