Combining passive acoustics and satellite oceanography to evaluate cetacean habitat in the South Atlantic Bight

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In the South Atlantic Bight (SAB), the Gulf Stream (GS) front and Gulf Stream Frontal Eddies (GSFEs) are known to provide important habitat for foraging seabirds, but their effect on cetacean abundance and distribution has not been considered. Using data from moored High-frequency Acoustic Record Packages (HARPs) in Onslow Bay, we assessed the effects of dynamic oceanography on odontocete vocalization rates. Satellite images of sea surface temperature during HARP deployments were used to identify local water masses (Gulf Stream, shelf waters and Gulf Stream frontal eddies) relative to HARP locations for three HARP deployments, representing a total deployment time of 313 days (10/10/2007 – 01/16/2008; 04/24/2009 – 08/9/2009; and 11/8/2009 – 02/24/2010). Both the total duration of all vocal events and the total duration of click events, respectively, were analyzed for all odontocetes together, and also for sperm whales (Physeter macrocephalus), Risso’s dolphins (Grampus griseus), short-finned pilot whales (Globicephala macrorhynchus), and delphinids separately. T he presence of GSFEs and the location of the GS front influenced cetacean vocalization rates and we discuss these findings in relation to the ecology of the study species. (Abstract ID 12484)