A visual and acoustic survey was conducted in the Great Bahama Canyon during June 2011 using an 18m power-catamaran.

The purpose of the survey is to improve our understanding of the baseline ecology of six species of cetaceans that inhabit the deep-oceanic waters of The Bahamas, including three species of beaked whales, sperm whales, short-finned pilot whales and melon-headed whales. We are integrating archived data and new data collected during ship surveys using individual photo-identification, molecular genetics, chemical markers (fatty acids, persistent organic pollutants, and stable isotopes), satellite telemetry and acoustic recordings. This inter-disciplinary approach will allow us to characterize the social structure, residency patterns, reproductive biology, diet, foraging ecology, habitat use and population structuring of key cetacean species. Information derived from this study is vital to learning how marine mammals respond to sounds in their environment, in particularly Navy sonars used during operational training.

A team of seven observers surveyed 2,782 km, resulting in 66 cetacean sightings, including sightings of all of our six target species. Acoustic detections were made for all target species using a 200m towed hydrophone and first-clicks from eight sperm whales were recorded to later determine size of animal from the click echo. When sea conditions allowed, a 6.8m skiff was launched for close approaches to obtain photographs, biopsy samples and deploy satellite tags. More than 8900 photographs were taken and 29 tissue samples were collected, including from all target species as well as from potential prey species. Nine satellite LIMPET tags were deployed on five of the six target species, including sperm whales (n=4), pilot whales (n=1), melon-headed whales (n=2), Blainville's beaked whales (n=1) and Cuvier's beaked whales (n=1). The two tags on the beaked whales transmitted detailed depth data, temperatures and locations, and the remaining tags transmitted locations and time-at-temperature (depth proxy) histograms. We have received over 850 location calculations, and over 9000 depth readings. The tag on the Blainville's beaked whale transmitted for 47 days after deployment.

This work is supported by a contract awarded to BMMRO from the US Department of Defence's Strategic Environmental Research and Development Program, administered by the US Army Corps of Engineers, Humphreys Engineer Center Support Activity, contract number W912HQ-11-C-0038.