Scientists and conservationists from 40 countries have signed an open letter calling for global action to protect cetaceans (whales, dolphins, and porpoises) from extinction. Half of all species are of conservation concern, with two on the edge of extinction according to the researchers, who called for urgent action.

“Let this be a historic moment when realizing that whales are in danger sparks a powerful wave of action from everyone: regulators, scientists, politicians and the public to save our oceans,” Mark Simmonds, a visiting research fellow at the University of Bristol who coordinated the letter, told the BBC.

Of the 90 living species of cetaceans, more than half now have a concerning conservation status according to the International Union for Conservation of Nature (IUCN). Thirteen species listed as “Critically Endangered” or “Endangered,”, seven as “Vulnerable” and seven as “Near Threatened,” whilst 24 species are “Data Deficient”. Additionally, there are 32 subspecies and other distinct cetacean populations that are presently either Endangered or Critically Endangered. With ongoing research, scientists are recognizing more populations of cetaceans that are discrete and require conservation action, the letter reads.

Environmentalists came up with the “save the whales” slogan in the 1970s, which spread around the world and created a movement to end commercial whaling. Although disturbed populations in most parts of the world have had a chance to recover from organized hunting, they are now facing myriad threats from human actions.

Cetacean populations are adversely affected by many interacting factors, including chemical and noise pollution, loss of habitat and prey, climate change, and ship-strikes. For many, foremost among these threats is fishing. An estimated 300,000 cetaceans are killed because of fishing every year.

This has raised the alarm among scientists, who argued we are moving closer to a number of preventable extinctions. And unless we take action now, future generations won’t experience a large number of these creatures. They recalled the decline of the North Atlantic right whale and the vaquita, a porpoise species with only 10 surviving individuals. And these will be followed by the inevitable decline of the baiji or Chinese river dolphin.

The baiji was identified as ‘Possibly Extinct’ by the IUCN in 2017 and, regrettably, there is little hope for this species, the scientists argued. In all cases, enough was known over the decline but there was a lack of political action.

Speaking with the BBC, Susan Lieberman of the Wildlife Conservation Society said she signed the letter to help scientists raise these issues more widely. “It is critical that governments develop, fund, and implement additional needed actions to better protect and save these iconic species – so they don’t end going the way of the baiji,” she said.

The scientists called on countries with cetaceans in their waters to take precautionary action to ensure these species and populations are adequately protected from human activities. This includes implementing appropriate and fully resourced monitoring. Improved technologies now offer new opportunities to observe and address problematic activities at sea.

At the same time, they asked all nations to work with and strengthen the relevant international bodies that seek to address threats to cetaceans. This mainly refers to the International Whaling Commission and the Convention for the Conservation of Migratory Species of Wild Animals. Both are generating important conservation initiatives, they argued.

“Whales, dolphins and porpoises are seen and enjoyed all over the world, and are valued as sentient, intelligent, social and inspiring species; we should not deny future generations the opportunity to experience them. They are also sentinels of the health of our seas, oceans and, in some cases, major river systems,” the letter concludes.