distribution in
the eastern and southeastern Caribbean Sea. S.L. Swartz, T. Cole, M.A.
McDonald, J.A. Hildebrand, E.M. Oleson, A. Martinez, P.J. Clapham, J.
Barlow, and M.L. Jones. 2003. Caribbean Journal of Science 39(2):195-208.
PDF available through journal website: www.caribjsci.org
ABSTRACT. Humpback whales (Megaptera novaeangliae) historically
ranged throughout the eastern and southeastern Caribbean Sea during
the winter months. Commercial whaling from the 1820s to the early
1900s depleted the population. A combined passive acoustic and visual
survey for humpback whales was conducted to assess the current winter
distribution of this species in areas where it was exploited to
depletion, and to evaluate the effectiveness of using passive acoustic
survey methods to detect and locate humpback whales. Visual surveys
were conducted independently but simultaneously with acoustic surveys
to compare both detection methods. Humpback whale song was detected
throughout the entire survey area, indicating that the species
continues to occupy its historical range. A total of 31 sightings were
made (n = 46 individuals, including three calves). In contrast, at
least 78 unique acoustic detections of different singing males was
made. The greater number of whales detected acoustically demonstrated
the advantage of passive acoustic methods over visual methods for
detecting male singing humpback whales; however, some sightings were
not detected acoustically, demonstrating that visual methods are
superior for detecting non-vocalizing whales. The number of whales
detected indicates that the abundance of humpbacks in the eastern and
southeastern Caribbean Sea is considerably lower than it was during
the 19th century whaling period, and much lower than present day
abundance in the primary wintering areas in the northeastern Greater
Antilles.
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