Nest locations of Mallard and Gadwall ducklings in Suisun Marsh, California

We assessed sources of mortality and quantified duckling survival rates for Anas platyrhynchos (Mallard) and Mareca strepera (Gadwall) ducklings that hatched on Grizzly Island (outlined in red) in Suisun Marsh, California from 2016 to 2019. Nest locations for radio-marked ducklings are shown in triangles and the upland nesting habitat shows the area searched for duck nests on and adjacent to the Grizzly Island Wildlife Area. Background Imagery Service Layer Credits: Light Gray Base: Esri, TomTom, Garmin, FAO, NOAA, USGS, EPA, USFWS.