NOAA Fisheries said today it will study whether the Atlantic humpback dolphin requires federal protection under the Endangered Species Act.
Urged on by a petition filed in September by the Animal Welfare Institute, the Center for Biological Diversity and Viva Vaquita, the agency agreed that an initial 90-day review was convincing enough to prompt a full-bore study likely to last about 12 months.
“The information … regarding the Atlantic humpback dolphin’s specific habitat requirements, low estimated abundance, fragmented distribution, and the immediate threat of fisheries bycatch and potential targeted harvest lead us to conclude that listing the species as threatened or endangered may be warranted,” NOAA Fisheries said.
The dolphin inhabits warm, shallow waters off the African coast ranging from Western Sahara to Angola.
Initial reviews suggest the population of the species currently numbers fewer than 3,000 individuals, half of whom are presumed to be mature.
“The evidence of recent work in some areas and a consensus of expert opinions indicate that most stocks … are small and that all stocks have experienced significant declines in recent decades,” the federal agency reported.
Researchers have identified “artisanal fishing bycatch” — or dolphins being unintentionally caught — in gillnets as among the principal causes of these declines.
“This threat has been identified or suspected throughout much of the species’ range and for as long as the species has been studied,” NOAA Fisheries said.
One study out of the Republic of Congo, for instance, identified 10 Atlantic humpback dolphins that were entangled as bycatch over a five-year period along a 60-kilometer stretch of protected beach.
The absence of similar monitoring elsewhere leads officials to suspect reported bycatch figures likely underestimate the true level of mortality. NOAA Fisheries noted that “the extensive spread of migrant fishermen across western Africa” probably aggravates the problem.
Declines in other fish species may increase fishing efforts and pressure, leading to increased bycatch risk for the dolphin, while “industrial fisheries compound this issue by competing for increasingly scant resources,” according to the agency.
To pass the initial 90-day review and clear the way for a more extensive species assessment, petitioners must present “substantial scientific or commercial information indicating that [listing] may be warranted.”
However, “conclusive information” indicating the species meets the ESA’s requirements for listing is not required for a positive 90-day finding.
In a 2015 report, NOAA Fisheries determined that “research is needed to establish the range, distribution, natural history, taxonomy, abundance, and fishery interactions of Atlantic humpback dolphins” and that high priority areas were Ghana’s Volta River region and western Togo.
“Conservation efforts are needed for Atlantic humpback dolphins,” NOAA Fisheries said in the 2015 report.
