Unprecedented Migratory Bird Die-Off: A Citizen-Based Analysis on the Spatiotemporal Patterns of Mass Mortality Events in the Western United States

Authors

Di Yang, University of Wyoming
Anni Yang, USDA National Wildlife Research Center, Fort Collins, COFollow
Jue Yang, University of Georgia
Rongting Xu, Oregon State University
Han Qiu, University of Wisconsin-Madison

ORCID IDs

Di Yang https://orcid.org/0000-0002-4010-6163

Anni Yang https://orcid.org/0000-0002-9535-2193

Jue Yang https://orcid.org/0000-0002-1399-8100

Han Qiu https://orcid.org/0000-0001-9962-2472

Document Type

Article

Date of this Version

4-1-2021

Citation

Yang, D., Yang, A., Yang, J., Xu, R., & Qiu, H. (2021). Unprecedented migratory bird die-off: A citizenbased analysis on the spatiotemporal patterns of mass mortality events in the western United States. GeoHealth, 5, e2021GH000395. https://doi. org/10.1029/2021GH000395

Comments

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License,

Abstract

Extensive, severe wildfires, and wildfire-induced smoke occurred across the western and central United States since August 2020. Wildfires resulting in the loss of habitats and emission of particulate matter and volatile organic compounds pose serious threatens to wildlife and human populations, especially for avian species, the respiratory system of which are sensitive to air pollutions. At the same time, the extreme weather (e.g., snowstorms) in late summer may also impact bird migration by cutting off their food supply and promoting their migration before they were physiologically ready. In this study, we investigated the environmental drivers of massive bird die-offs by combining socioecological earth observations data sets with citizen science observations. We employed the geographically weighted regression models to quantitatively evaluate the effects of different environmental and climatic drivers, including wildfire, air quality, extreme weather, drought, and land cover types, on the spatial pattern of migratory bird mortality across the western and central US during August-September 2020. We found that these drivers affected the death of migratory birds in different ways, among which air quality and distance to wildfire were two major drivers. Additionally, there were more bird mortality events found in urban areas and close to wildfire in early August. However, fewer bird deaths were detected closer to wildfires in California in late August and September. Our findings highlight the important impact of extreme weather and natural disasters on bird biology, survival, and migration, which can provide significant insights into bird biodiversity, conservation, and ecosystem sustainability.