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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: Paul C Cross
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
Remotely sensed elk locations were derived from satellite and Unmanned Aerial Systems (UAS) imagery collected during the winter of 2018 and the winter and spring of 2019 at the National Elk Refuge in Jackson, Wyoming and compared to locations from Global Positioning System (GPS) collars from 2017 - 2019. This data release provides the source, date, time, latitude, and longitude of elk locations and the type of analyses the location data were used for in the accompanying manuscript by Graves and others 2021. DOI will be provided once supplied by the journal.
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
These data represent projections of peak instantaneous rate of green-up date (PIRGd) and spring scale across Wyoming from 2000-2099. Annual data is provided in gridded time series at ~4 km spatial resolution. Projections were generated by applying linear mixed models to contemporary remote sensing data, and applying model parameters to future climate projection data from the MACA dataset. Projections were generated for 5 global climate models (GCMs) and 2 representative concentration pathway (RCP) scenarios: RCP 4.5 and RCP 8.5. Data starting in 2000 are provided to help assess accuracy of model projections against contemporary datasets, and provide a platform for comparison to projections for future years. These...
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...
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