Historical occurrence and distribution of humpback whales in the eastern and southern Caribbean Sea, based on data from American whaling logbooks

Résumé

The best-known present-day wintering areas for the North Atlantic population of humpback whales (Megaptera novaeangliae) are in the northern West Indies, notably off the island of Hispaniola. However, it is known that in the nineteenth century American whalers hunted humpbacks in the Windward Islands (primarily from Guadeloupe southwards), along the coast of Trinidad, in the Gulf of Paria and westwards along the Venezuelan coast. To investigate the historical distribution and occurrence of humpback whales, data were extracted from nineteenth century American whaling logbooks and journals covering 48 voyages by 29 vessels to the West Indies from 1823-1889. Humpback whale records in these documents came from a geographical area that encompassed Haiti to the coast of Venezuela. Of 807 records in which whales were mentioned (as sightings, strikes or catches), the largest number was from the Windward Islands and Venezuela, especially St Vincent and the Grenadines (319 records covering an estimated 958 humpbacks), Guadeloupe (190 records, 592 humpbacks), Dominica/Martinique/St Lucia (74 records, 193 humpbacks) and Venezuela (64 records, 216 humpbacks). These totals should be regarded only as approximate indicators of the relative abundance of whales since the effort involved cannot be meaningfully quantified. Similarly, effort-uncorrected data suggest that the peak months for humpback whales in the Windward Islands were February, March and April. Few sightings were recorded off the Dominican Republic after March, but this may reflect a lack of effort there in April and May. However, humpbacks apparently were abundant in the Windwards in April and even May, which is not the case in the major present-day wintering areas off Hispaniola. With one notable exception, there is little evidence in the logbooks and journals that humpbacks were taken on a more than casual basis in waters off Hispaniola, where the major aggregations are found today; possible explanations for the marked contrast in present versus historical distribution are discussed. The highly seasonal visitation of the West Indies by the American nineteenth-century whalers precludes a meaningful investigation of the possibility that some humpbacks from the Southern Hemisphere migrated to the Caribbean Sea in the austral winter.