They are the most extraordinary of fish, resembling ‘fence scissors with fins’.
The sawfish, which is a kind of ray, is also one of the most endangered fish in the oceans.
Once found along the coastlines of 90 countries, the animals are thought to be extinct in more than half of them, according to a new study.
They have disappeared due to habitat loss and entanglement in fishing nets, experts said.
Their “saw,” which evolved to touch and attack prey, has now become a liability, making them prone to getting caught in fishing gear.
“Through the plight of sawfish, we are documenting the first cases of a wide marine fish being driven by overfishing to local extinction,” said Prof Nick Dulvy of Simon Fraser University (SFU) in British Columbia, Canada.
Of the five species of sawfish, three are critically endangered, while two are listed as endangered according to the International Union for Conservation of Nature (IUCN)’s Red List of Endangered Species.
The sawfish was previously suspected to be widespread in 55 countries, the study said.
There are 18 countries where at least one species of sawfish is missing, and 28 more where two species have disappeared.
The list of countries where sawfish became extinct now includes China, Iraq, Haiti, Japan, Timor-Leste, El Salvador, Taiwan, Djibouti and Brunei.
The US and Australia appear to be the last strongholds for the species, which are considered ‘lifeboat nations’, where sawfish are better protected.
The study, published in Science Advances, also identified eight countries where urgent action could make a major contribution to the extinction of the species through conservation efforts.
These are Cuba, Tanzania, Colombia, Madagascar, Panama, Brazil, Mexico and Sri Lanka.
“While the situation is dire, we hope to make up for the bad news by highlighting our informed identification of these priority countries with hopes of rescuing sawfish in their waters,” said Helen Yan of SFU.
She said it was still possible to restore sawfish to more than 70% of their historic size, “if we act now”.
International trade in sawfish is prohibited under the Convention on International Trade in Endangered Species of Flora and Fauna, but there is still targeting and accidental killing.
Sawdust fins and teeth are sold as trophies, food or medicine and as spores for cockfighting.
Sonja Fordham, a study researcher and president of Shark Advocates International, said there were opportunities to “bring these extraordinary animals back from the edge”.
But she warned that ‘we have too little time to save them’.
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