IUCN Red List Assessment
Red List Category
Red List Criteria
Partly because of their small size, phocoenids are exceptionally vulnerable to incidental mortality in gillnets (e.g., Jefferson and Curry 1994). Neophocaena phocaenoides is smaller than N. asiaeorientalis (thus, if anything, probably even less able to break free once entangled in a net) and incidental mortality in fishing gear has been documented throughout its range. Fishing effort with gear documented to catch finless porpoises (including gillnets, trawls, stow nets and seines) is intense in many areas where the species occurs or occurred. With some of the largest concentrations of humans in the world living along the shores of and harvesting the resources from the warm coastal waters inhabited by Indo-Pacific Finless Porpoises, the impacts of human activities on this species must be considerable. Although not quantified rigorously as for some N. asiaeorientalis populations, regional declines (and possible local extirpations) of N. phocaenoides have been reported, presumably due to fishing pressure, coastal development and industrialization, pollution and heavy vessel traffic (see Reeves et al. 1997, Collins et al. 2005, Braulik et al. 2010).
Although the data are far from sufficient to make a rigorous quantitative assessment of population trend for this species throughout its range, the scale of threats is large enough over enough of the range to suspect and infer a decline of at least 30% over the last three generations (about 50 years, see Taylor et al. 2007). The factor most responsible for such a decline would be incidental mortality in fisheries, but the loss and degradation of habitat are likely contributing factors as well. None of the threats has been seriously addressed in any part of the species’ range, even though threat levels are likely increasing.
Therefore, as is true of the other species of finless porpoise (N. asiaeorientalis), the Indo-Pacific species qualifies for Vulnerable A2cde, considering that the causes of the suspected/inferred decline in population size—bycatch (interpreted here as “exploitation”), decline in habitat quality, and possibly pollution—have not ceased and are not well understood.