Anonymized ground and aerial data from a 2019-2021 study investigating grizzly bear-army cutworm moth (ACM) interactions in Glacier National Park, MT, USA
Data files
Jun 16, 2026 version files 66.44 KB
Abstract
The army cutworm moth (ACM) migrates great distances to aggregate in talus slopes of the Rocky Mountains during the summer months. Their high energy content is attractive to grizzly bears, which ascend mountains to consume them. From 2019 to 2021, we implemented two survey techniques to elucidate grizzly bear-ACM interactions in Glacier National Park, Montana. We hypothesized A) ACM occurrence would be positively associated with cool, wet, air-filled talus environments located near nectar resources, and B) grizzly bear foraging would be guided by ACM occurrence. We used field surveys of talus to create models of ACM occurrence and executed helicopter surveys of these slopes to create models of grizzly bear foraging. We determined ACM occurrence was primarily influenced by the physical characteristics of talus that provided stable, cool microclimates. We also determined that ACM occurrence was the most influential predictor of grizzly bear foraging. Our models can help park managers develop access management strategies to limit recreational impacts on moth-foraging grizzlies.
General information
Journal Name: Biological Conservation 320 (2026) 111892, https://doi.org/10.1016/j.biocon.2026.111892
Title: Anonymized ground & aerial data from a 2019-2021 study investigating grizzly bear-army cutowrm moth (ACM) interactions in Glacier National Park, MT, USA.
Author: Erik Peterson, Washington State University, erik.d.peterson@wsu.edu
Abstract: 30 m resolution data is presented in three parts: 1) ACM detection data from ground surveys (ACMLocations_Anonymized_Project_Glac2019Sci0012.csv), 2) grizzly bear ACM foraging sign detected during ground surveys (GbearMothForagingLocationsGround_Anonymized_Project_Glac2019Sci0012.csv), & 3) grizzly bear ACM foraging detection information from aerial surveys. All sensitive data from these data sets has been removed (GbearMothForagingLocationsAerial_Anonymized_Project_Glac2019Sci0012.csv).
Research Domain: 1.6 Biological sciences
Keywords: Generalized linear models; Glacier National Park; Insect migration; Montana; Recreation; Species distribution models; Talus
Funding Information: Glacier National Park Conservancy grant GLAC-2019-SCI-0012
Description of files and data
Metadata:
1) ACM DETECTION DATA FROM GROUND SURVEYS
- FID: Sequential # by data row.
- Survey Unit #: Anonymized numeric # that identifies the survey unit where ACM detection occurred.
- PlotID: # identifier for survey plot where ACM detection occurred.
- Date: Month-day-year of ACM detection.
- Year: Year of ACM detection.
- Month: Month of ACM detection.
- TotMoths: Total # of ACM detected at survey plot.
- ACM: 0/1 code for survey plot ACM status; 0 = ACM not detected, 1 = ACM detected.
- DomRock: Categorized dominant geological formation at survey plot.
- TalDepth: Measured depth of talus at survey plot center.
- TalPhoto: Categorized size for the majority of surficial talus at the survey plot.
- Talpositio: Categorized description of survey plot's proximity to exposed bedrock; adjacent bedrock = plot 10 or less m from exposed bedrock, open slope = plot more than 10 m from exposed bedrock.
- Elevation: Elevation, in meters, at the survey plot.
- Slope: Degree angle of slope at the survey plot.
- Aspect_H: Measure of solar loading at survey plot, where aspect is folded 0-180 degrees & oriented on a SW-NE axis.
- TerrRugged: Terrain variation within a 3x3 neighborhood of cells around the target cell (survey plot).
- Wet2020: Averaged 2020 terrain wetness value at survey plot. Value is a proxy for snowmelt from three cloud-free Landsat 8 images - 3 July, 4 August, & 5 September 2020.
- Grn080420: Terrain greenness value at survey plot. Value is a proxy for peak summer 2020 photosynthetic activity in alpine areas from a cloud-free Landsat 8 image from 4 August.
- USGSRock: Descriptive category geological formation from USGS map dataset.
- USGSRock_#: Numeric category for geological formation from USGS map. Matches the category # of source data.
2) GRIZZLY BEAR ACM FORAGING SIGN FROM GROUND SURVEYS
- Date: Month-day-year of foraging sign detection.
- Year: Year of foraging sign detection.
- Month: Month of foraging sign detection.
- Survey Unit #: Anonymized numeric # that identifies the survey unit where the sign of a grizzly bear foraging for ACM was detected.
- Detection: Whether the ACM foraging sign was located inside or outside a survey plot.
3) GRIZZLY BEAR ACM FORAGING DETECTION INFORMATION FROM AERIAL SURVEYS
- Date: Month-day-year of grizzly bear observation.
- Year: Year of grizzly bear observation.
- Month: Month of grizzly bear observation.
- Survey Unit #: Anonymized numeric # that identifies the survey unit where grizzly bear foraging for ACM was detected.
- # Gbears: The # of gbears observed in the group.
- Age: Estimated age of the grizzly bears in the group.
- 1st Behavior: The first behavior observed during the grizzly bear observation.
- Flee: Yes/no whether grizzly bears were observed fleeing.
- ACM: Yes/No whether ACM foraging behavior was observed.