Small whales rapidly disappearing from world's oceans

Posted: 28 June 2009

Small whales are disappearing from the world's oceans and waterways as they fall victim to fishing gear, pollution, and habitat loss - threats compounded by a lack of conservation measures such as those developed for great whales.

Indus river dolphin
Indus river dolphin
Rescue of Indus river dolphin (Platanista indi), Sukkur, Province of Sind, Pakistan, Kirthar canal. Photo © François Xavier PELLETIER / WWF-Canon
According to a WWF report, inadequate conservation measures are pushing small cetaceans - such as dolphins, porpoises and small whales - toward extinction and yet they receive much less political attention than their larger cousins.

"Although great whale species of the world are by no means secure and still require conservation attention, the situation is just as critical for these smaller, seemingly forgotten species," said Heather Sohl, Species Policy Officer at WWF-UK.

While great whales are now afforded more protection through the international commercial whaling moratorium, in effect since 1986, smallcetacean hunts continue around the globe, largely unmanaged and unchecked by the international community.

Vaquita or Gulf of California Harbor porpoise
Vaquita or Gulf of California Harbor porpoise
Vaquita or Gulf of California Harbor porpoise (Phocoena sinus) caught in fishing nets, Baja California, Mexico. Photo © National Geographic Stock/Flip Nicklin/Minden Pictures / WWF
For example, the hunt of 16,000 Dall's porpoises every year in Japan is considered unsustainable. Yet several of the pro-whaling nations taking part in the International Whaling Commission (IWC) meeting this week object to discussing small cetacean conservation.

Lack of data

"It is time for the IWC and its members to take full responsibility for the conservation future of all whales great and small. The IWC - and the world - must not ignore the small whales of our planet until it is too late," said Heather Sohl.

A significant disadvantage smaller whale species face compared to great whales is a crippling lack of data on their numbers and habits. Forty of the 69 small cetacean species,(58 per cent) are classified by IUCN as 'data deficient', meaning that there is not enough information available to determine their population status.

According to the IUCN Red List, population trends - whether the species is increasing or decreasing in number - are unknown for 60 of the 69 small cetacean species. The nine remaining species are in decline.

Only four out of 15 species (27 per cent) of great whales are listed as data deficient, despite many of the difficulties encountered in studying smaller whale species also applying to the great whales.

Ganges river dolphin
Ganges river dolphin
Plataniste or Ganges river dolphin (platanista gangética), Karnaphuli river, Bangladesh. Photo © François Xavier PELLETIER / WWF-Canon
Great whales also have more protection in international conservation efforts. Almost all great whale species, for example, have the strongest level of protection offered by CITES - a conservation convention which regulates international trade in protected wildlife species - compared to just 17 per cent of dolphin and porpoises species. In addition, the Convention on Migratory Species (CMS) protects 87 per cent of great whale species, but less than half of smaller whale species.

Small cetaceans fulfill a critical role in their environment, stabilising and ensuring a healthy and productive ecosystem. They are also part of the highly profitable whale and dolphin watching industry worldwide, which generates over US $1.5 billion each year.

"If small cetaceans are not central to negotiations on current whaling, it is possible that conservation successes achieved for great whales could simply result in a shift of problems from great whales to small cetaceans," the report states.

NOTE: After days of talks, the International Whaling Commission, meeting in Madeira last week, set aside most major decisions until later in the year. It did, however, adopt a major climate change resolution co-sponsored by the United States and Norway. This states that climate change is a key threat to whales, and urges governments to commit to reducing their carbon emissions at the UN Climate meeting in Copenhagen in December. It also directs IWC to engage in external climate change meetings in the run up to Copenhagen.