They are the most extraordinary fish, resembling “hedge trimmers with fins”.
The sawfish, which is a species of ray, is also among the most endangered fish that live in the oceans.
Previously found along the coast of 90 countries, animals are now considered extinct in more than half of them, according to a new study.
They are disappearing due to habitat loss and entanglement in fishing nets, experts said.
Their “saws”, which evolved to detect and attack prey, have now become a problem, making them prone to being caught by fishing gear.
“Through the plight of the sawfish, we are documenting the first cases of large marine fish that were driven to local extinction by overfishing,” said Professor 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) Red List of Threatened Species.
Previously widespread, sawfish is now considered extinct in 55 countries, the study said.
There are 18 countries where at least one species of sawfish is missing and another 28 where two species have disappeared.
The list of countries where sawfish is extinct now includes China, Iraq, Haiti, Japan, Timor-Leste, El Salvador, Taiwan, Djibouti and Brunei.
The United States and Australia seem to be the last strongholds of the species, considered “lifeboat nations”, where sawfish are better protected.
The study, published in Science Advances, also identified eight nations where urgent action could make a major contribution to saving the species through conservation efforts.
They 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 nations with the hope of saving sawfish in their waters,” said Helen Yan of SFU.
She said it is still possible to restore sawfish to more than 70% of its historic range, “if we act now”.
International trade in sawfish is prohibited by the Convention on International Trade in Endangered Flora and Fauna Species, but selective and accidental deaths still occur.
The sawfish’s fins and teeth are sold as trophies, food or medicine and as spurs for cockfights.
Sonja Fordham, a study researcher and president of Shark Advocates International, said there were opportunities to “bring these extraordinary animals back from the brink.”
But she warned that in many places, “we are running out of time to save them”.
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