Extinction alert issued for vaquita porpoise

The International Whaling Commission (IWC) said it has issued an extinction alert for the endangered vaquita porpoise, whose population is estimated to have shrunk to less than a dozen.

The IWC’s scientific committee highlighted in a report an 83 per cent drop in the vaquita’s population between 2015 and 2018 to only nine or 10 of the marine animals in total.

The critically endangered vaquita is the world’s smallest porpoise and native to Mexico’s Gulf of California. It has been imperiled by illegal gillnet fishing for an endangered fish called the totoaba, whose bladder is highly valued in Asia for use in traditional medicine. Mexico’s government has been under pressure to crack down on the practice.

Extinction is the disappearance, forever, of an entire species. A species or sub-species is considered extinct when there is no reasonable doubt that the last individual has died. A species or sub-species is presumed extinct when exhaustive surveys in known and expected habitat have failed to record a single individual.

Whales, dolphins and porpoises are a group of marine mammals collectively known as cetaceans.

Vaquita porpoise

•  According to the International Union for Conservation of Nature (IUCN), vaquita (Phocoena sinus) is the most endangered marine mammal species in the world.
•  It has a very restricted distribution, occurring only in the northern part of the Gulf of California in Mexico, an area that is rich in fish and shrimp.
•  Fishing is thus a major source of income for the people there, who almost exclusively use gillnets, but vaquitas can also become accidentally wrapped in the nets.
•  The decrease in the vaquita population is also related to the totoaba, a large fish that also only lives in the Gulf of California.
•  Because totoaba and vaquita are similar in size, gillnets illegally set for totoaba are the deadliest for vaquitas.
•  Scientists agree that for vaquitas to survive in the wild, gillnet fishing must end within vaquita habitat.
•  Numbers have fallen from a population of approximately 570 in 1997 to around 10 animals in 2018. This number appears to have remained fairly constant since 2018, probably due to increased enforcement of gillnet bans and removal of nets.
•  But this effort needs to be 100 per cent effective to start reversing the decline and bringing the vaquita back from the brink of extinction.
• The vaquita is about 5 feet long and is one of the smallest members of the dolphin, whale, and porpoise family. Females are longer than males, but males have larger fins.
• Vaquitas have small, strong bodies with a rounded head and no beak. They have black patches around their eyes and lips and small, spade-shaped teeth. Vaquitas also have triangle-shaped dorsal fins in the middle of their backs, which are taller and wider than in other porpoises.
• Vaquitas feed on small fish, crustaceans (such as shrimp), and cephalopods (such as squid and octopuses).
• Vaquitas can live for at least 21 years.

International Whaling Commission

• The International Whaling Commission was established in 1946 as the global body responsible for management of whaling and conservation of whales.
• It was set up under the International Convention for the Regulation of Whaling which was signed in Washington DC in December 1946.
•  The IWC has 88 member countries.
•  The mandate has not changed but many new conservation concerns exist and the IWC work programme now also includes bycatch and entanglement, ship strikes, ocean noise, pollution and debris, and sustainable whale watching.
•  The work of the Commission is divided across six committees which in turn are comprised of a series of sub-groups.
•  Some of these sub-groups are long-term, standing committees and some are established to complete a specific piece of work.
• The groups are chaired by Commissioners, other members of national delegations or subject matter experts from within the wider IWC community.