A visual and acoustic survey of the Caribbean islands from St. Kitts to Trinidad was conducted for humpback whales on the 224 foot NOAA research vessel Gordon Gunter February-April, 2000. The acoustic survey was conducted using directional (DIFAR) sonobuoys.

Only the males are expected to be singing and only about 40 percent of the singers will be detected during a typical 70 minute duration acoustic monitoring period. We detected a minimum of seven humpback singers during this survey of Martinique, suggesting about thirty humpbacks are present. Given the strong winds, it was not surprising that the only humpback seen near Martinique was the one acoustically pursued and sighted near sonobuoy number 50. This particular humpback was acoustically detected initially from 36 nautical miles range. The number in parentheses beside each buoy is the minimum number of whales heard on each buoy.

Click to see larger view. Ship track and sonobuoy deployments for the first leg of the survey.

Click to see larger view. Compass vectors to each whale detection from each DIFAR sonobuoy deployed during the survey of Martinique.