Evaluating Sea Duck Detectability in the Puget Sound Winter Ambient Monitoring Program

Project Number: 156
Year Funded: 2019
Lead Institution(s): US Geological Survey
Project Lead: Sarah J. Converse
Collaborator(s): Kyle Spragens (Washington DFW), Jamie Brusa (UW), Matt Farr (UW)
Location: Salish Sea
Focal Species: All Sea Ducks, Bufflehead (Bucephala albeola), Barrow’s Goldeneye (Bucephala islandica), Common Goldeneye (Bucephala clangula), Harlequin Duck (Histrionicus histrionicus), Long-tailed Duck (Clangula hyemalis), Common Eider (Somateria mollissima), King Eider (Somateria spectabilis), Spectacled Eider (Somateria fischeri), Steller’s Eider (Polysticta stelleri), Common Merganser (Mergus merganser), Hooded Merganser (Lophodytes cucullatus), Red-breasted Merganser (Mergus serrator), Black Scoter (Melanitta americana), Surf Scoter (Melanitta perspicillata)
Project Description: Monitoring the abundance and density of wintering sea ducks in the U.S. portion of the Salish Sea is achieved annually through aerial surveys conducted by the Washington Department of Fish and Wildlife (WDFW). These surveys provide information regarding the wintering population status and trends of several sea duck species, information which is necessary for population and habitat management. However, raw counts from WDFW aerial surveys tend to underestimate the number of individuals due to imperfect detection and movement away from the aircraft. We seek to develop a correction factor for aerial survey counts of sea ducks by species using photographs collected during March 2012. Project Objectives: 1) Evaluate whether there is a need for further digital image processing of the 2012 data, 2) Complete data analyses based on imagery to estimate correction factors that will provide quantitative information on availability and detection of sea ducks by the Puget Sound Ambient Monitoring Program (PSAMP) observers, 3) Incorporate species-specific correction factors into winter estimates of sea duck species monitored through PSAMP.
Project Reports: 

Interim Report FY21
Interim Report FY22
Final Report

Evaluating Sea Duck Detectability in the Puget Sound Winter Ambient Monitoring Program