A threefold increase in documented cetacean diversity in the Windward Dutch Caribbean

Cetacean diversity in the Windward Dutch Caribbean remains poorly known, with only six species previously reported in its waters. By contrast, cetacean diversity is well documented in neighbouring islands, including Puerto Rico and the Virgin Islands, as well as in parts of the Lesser Antilles, where 23 species are known to occur. Based on 40 days of systematic boat-based surveys conducted over five years, supplemented by opportunistic sightings, we update the information of cetacean diversity within the Exclusive Economic Zones of Saba, St. Maarten, and St. Eustatius. Each record was individually reviewed, and first-time species reports were validated through photographic evidence or confirmation by researchers with recognized expertise. A total of 124 cetacean sightings were recorded, documenting 17 species in the Windward Dutch Caribbean. These findings demonstrate that this previously understudied area harbors a cetacean diversity comparable to that of neighboring Antillean islands and provide new insights into coastal cetacean distribution in the region. This work establishes a baseline for future research and conservation planning around these islands and across the broader Northern Lesser Antilles.