Average radar intensity over the Great Dismal Swamp Refuge (GDSR) in North Carolina and Virginia has a close relationship with changing groundwater levels. Using PALSAR and RADARSAT2 Interferometric Synthetic Aperture Radar (InSAR) observations, the FWS estimated surface water level changes over the GDSR with repeat satellite radar imagery. This state-of-the-art research was done by Dr. Jinwoo Kim and Dr. Zhong Lu at Southern Methodist University with funding support by the U.S. Geological Survey and local logistical support by the FWS.
Land Use and Land Cover Change
Remote Sensing Missions and Data
The FWS, Midwest Region has begun an evaluation program to understand the utility of a 4-camera strip video sampling system for migratory bird counts. The camera, although now outdated and no longer made, was originally contracted by the Department of Energy from HiDef Surveys of England for offshore wind energy impact studies off the Atlantic coast. FWS scientists successfully obtained imagery with this camera using the Region 3 Partenavia Observer aircraft in late May 2015. The next challenge is to determine if the imagery can be of use over land for identifying migratory birds.
In 2014, a 220,000-acre fire burned within the Kenai National Wildlife Refuge, Alaska. To assess the impact of the fire, new high-resolution orhophotography and elevation data were desired for at least part of the burn. However, acquiring these products using lidar and traditional photogrammetry would be cost prohibitive.
Large river ecosystems are an important functional part of the landscape in the southeastern United States. The extent and condition of large river floodplains greatly affect the quality of fish and wildlife habitat and the supply of important ecosystem goods and services. To better understand patterns of floodplain inundation, scientists used 1,334 Landsat images over 51 Landsat scenes collected under a variety of hydrologic conditions from 1983 to 2011.
The Water Resources Division of the Region 6 FWS generated elevation data for the creation of a storage-capacity curve for MacFarlane Reservoir, which supplies water to the Arapaho National Wildlife Refuge (ANWR) located in north central Colorado. The reservoir was originally built in 1915, repaired and reconstructed in 1962, and purchased by the FWS in 1993; the reservoir provides nesting and migration habitat for several bird species and is a water source for habitat creation and management at the refuge.
When railway tracks are located close to wetlands, rivers, or lakes, dynamic water level changes can have substantial economic and environmental impacts on railroad operations. For example, BNSF Railway is spending millions of dollars to raise track beds through the Devils Lake region of North Dakota, where rising lake levels threaten to flood the existing tracks. As a result, there is a need to accurately model watersheds and landscapes for environmental engineering and railroad operations purposes using wetland and surface water mapping tools.