Imagery collected via a small unmanned aircraft system (sUAS) is being used to assess available breeding habitat of Federal- and State-listed threatened and endangered bird species at Havasu National Wildlife Refuge (NWR) near Needles, California. High-resolution, color-infrared imagery collected with sUAS is being analyzed in conjunction with vegetation, topography, bathymetry, differential-GPS, and species-specific breeding habitat criteria. This combined information will help refuge managers better understand the relationships between existing vegetation, water levels, and available avian breeding habitat within Topock Marsh, and will be used in developing the refuge’s comprehensive conservation plan (CCP). Havasu NWR and its 4,000-acre Topock Marsh have been identified by the Fish and Wildlife Service (FWS) as critical breeding habitat for Lower Colorado River migratory bird species. Results of this work will provide FWS with the tools needed to help make science-based decisions on operating the refuge’s water intake infrastructures to maximize the amount of available breeding habitat for these sensitive birds. Completing the CCP will support the refuge’s future water management decisions to maintain quality habitat within Topock Marsh as mandated by Congress.
Small unmanned aircraft system collected color-infrared image samples of vegetation at Havasu National Wildlife Refuge, near Needles, California (left to right: color-infrared, stretched color-infrared, natural color, and NDVI [Normalized Difference Vegetation Index]). (USGS Image)