Abstract: During the summers of 2004 and 2005, researchers surveyed cetacean presence along the continental slope of the northern Gulf of Mexico. Towed, passive acoustic hydrophones were used to identify locations along the cruise tracks where sperm whales were encountered and not encountered. During both summers, 35 groups of sperm whales (Physeter macrocephalus) were encountered at a frequency of about one group every 120 nmi of survey effort. To assess the linkages between surface oceanography and the distribution of sperm whales, surface ocean color from NASA's Moderate Imaging Spectroradiometer (MODIS) and surface dynamic height from NASA's Earth orbital altimeters were evaluated in conjunction with survey data. Most sperm whale groups were found within regions of enhanced sea surface chlorophyll (SSC), particularly 2 wks after the initial development of locally higher SSC anomalies. Results from this study indicate sperm whale distribution in the Gulf of Mexico is linked to surface oceanography at shorter time scales than previously documented.
Key Words: sperm whale, Physeter macrocephalus, sea surface chlorophyll, habitat, Gulf of Mexico
Document Type: Research article
Page Numbers: 358-366