Finless porpoise

How it lives

Finless porpoises are usually alone, in mother and calf pairs or in small groups of up to about 10. They are less acrobatic than dolphins and often avoid boats. Males mature at about 4 to 6 years and females at about 6 to 9 years. Gestation lasts about 10 to 11 months, and breeding is in late spring and early summer. Calves are born darker and lighten as they grow.

Where it goes

Finless porpoises live in shallow coastal water, from the Persian Gulf through South and Southeast Asia to Indonesia and north to the Taiwan Strait. Fine-scale movements are poorly known, and they are often hard to spot because they rarely approach boats.

We only draw a journey on the map when scientists have tracked it or clearly documented it. For this animal we have not found one yet.

Populations

Vulnerable worldwide for this species (IUCN, 2017), listed on CITES Appendix I and CMS Appendix II. Surveys show declines in numbers and range since the late 1970s. A February 2004 survey in Bangladesh estimated about 1,382 (a wide margin of error, CV 54.8 percent). Hong Kong and nearby waters hold roughly 200, according to a local conservation group. Scientists now split the genus into three species: the narrow-ridged finless porpoise (Endangered) is a separate species from this Indo-Pacific one.