A Spatio-Temporal Change Analysis of Shorebird Habitat Using Remote Sensing at Stillwater National Wildlife Refuge, NV

Abstract

Stillwater National Wildlife Refuge provides critical wetland stopover habitat for thousands of breeding and non-breeding migrating shorebirds during the spring and fall seasons. Habitat loss and degradation at the refuge due to climate change and human activities are of great concern to shorebird conservation groups. Evaluations of critical habitat features utilizing GIS can be leveraged as powerful, cost-effective tools in shorebird conservation and management efforts. In this study, three years (2001, 2011, and 2019) of remote sensing data captured during the fall season were analyzed for changes in select land cover factors impacting quality of shorebird habitat: presence of surface water using the Modified Normalized Difference Water Index (MNDWI), preferred land cover types, food and shelter availability using Normalized Difference Vegetation Index (NDVI), and human disturbance using impervious surface data. Results successfully detected temporal changes in many of the select environmental factors, including sizeable increases in NDVI and MNDWI results, both in value and spatial distribution, and notable transitions between land cover classes and their represented areas. Findings support the ongoing habitat conservation efforts at the refuge and demonstrate the use of remote sensing and GIS techniques in monitoring land cover conditions related to vital migratory shorebird habitat.