AUTHORS: Jeffrey Edwards, Missouri Cooperative Fish & Wildlife Research Unit, School of Natural Resources, University of Missouri; Dr. Lisa Webb, U.S. Geological Survey, Missouri Cooperative Fish & Wildlife Research Unit; Dr. Drew Fowler, U.S. Geological Survey, Louisiana Cooperative Fish & Wildlife Research Unit; Paul Link, Louisiana Department of Wildlife & Fisheries; Dr. Chris Nicolai, Delta Waterfowl
ABSTRACT: Migration is an important life history strategy that many waterbirds employ to exploit seasonally available resources and maximize fitness. However, migratory events are energetically demanding, and waterbirds use stopover sites during migration to rebuild energetic reserves. During spring migration, habitat quality at available stopover sites has the potential to exert cross-seasonal effects on breeding season population demographics. Wetland availability during the migratory period can be temporally dynamic within and across years as well as spatially variable throughout the migration corridor. Only recently has quantifying the spatial and temporal extent of available wetlands at broad scales become possible with remote sensing technologies. However, little is known about how temporally and spatially dynamic wetland availability may influence waterfowl resource selection during the non-breeding season. In this study, we collected movement data from 350 blue-winged teal (Spatula discors) marked with GPS-GSM transmitters to assess the effects of inundated wetland availability on blue-winged teal resource selection during the autumn and spring migrations (2019 – 2024). We used the Dynamic World dataset to quantify temporally and spatially dynamic inundated wetlands and intersected this data layer with landcover types from the National Land Cover Database. Combining these data sources, we will use an integrated step selection function to evaluate how blue-winged teal resource selection varies with inundated wetland availability at two-week intervals. The spatial extent of each two-week interval will be based on sample wide kernel density estimates of use. Results from this study can help inform wetland conservation and management practices for early autumn and late spring migrating waterbirds such as blue-winged teal. Specifically, these results can inform how early autumn wetland inundation and maintaining water into spring may support waterbirds whose life history strategies include this migration phenology.
