More than 50 countries have agreed to protect shortfin mako sharks, an endangered species that has been teetering on the brink of extinction due to fishing overexploitation.

The decision has been welcomed by conservationists and scientists who have worked for years to enact a fishing ban on the species, Isurus oxyrinchus, although they say the victory may only be temporary.

The agreement, led by Canada, the U.K., Senegal and Gabon, was made this week at the annual meeting of the International Commission for the Conservation of Atlantic Tunas (ICCAT), a coalition of 52 fishing nations that focuses on the management of tunas and tuna-like species. By the meeting’s end, countries had agreed “to end overfishing immediately and to gradually achieve biomass levels sufficient to support maximum sustainable yield (MSY) by 2070,” according to a press release.

A full retention ban on shortfin mako sharks in the North Atlantic — meaning fishers will not be allowed to land the sharks, even those caught accidentally — will take effect in 2022 and extend into 2023. After that, fishing nations in the North Atlantic will only be able to land mako sharks if the total mako bycatch from the previous year has not exceeded 250 metric tons. In comparison, the European Union alone landed 1,261 metric tons in 2020, according to data compiled by the Standing Committee on Research and Statistics (SCRS), the ICCAT’s scientific advisory body.

Shortfin mako sharks are one of the fastest creatures in the ocean, with reported speeds of up to 74 kilometers per hour (45 miles per hour). But they’re also very slow to grow and mature: males are unable to reproduce until they are 9 years old and females 19 years old. They also have a three-year reproductive cycle and a gestation period of 18 months. This slow breeding cycle has made them “exceptionally vulnerable” to overfishing, experts say.

The mako shark’s speed and strength has made the species a desirable target for sports fishing. They’re also incidentally caught by long lines and gillnet gear. Instead of releasing them, fishers have historically kept them and sold their meat — a practice that will be prohibited under the retention ban.

While the global population of mako sharks is unknown, stock assessments have shown that the population in the Mediterranean has declined by 96%, and the North Atlantic population is expected to decline by 60% over the next decade.

In 2017, the SCRS recommended an immediate and full retention ban on mako sharks in the North Atlantic, arguing that only this action would provide at least a 70% probability for rebuilding stock of the species by 2070. This recommendation was renewed in 2019. However, the ICCAT chose not to enact a full ban on either of those occasions.

In 2019, the species saw its conservation status worsen from vulnerable to endangered on the IUCN Red List, and strict regulations imposed on its trade under CITES, the global convention on wildlife trade.

Sandra Altherr of the German NGO Pro Wildlife says this ban on shortfin mako shark fishing is a “positive signal,” but that a short ban will do little to protect the species in the long term.

“It was the first agreement at all on the mako shark,” Altherr told Mongabay in a phone interview. “So yes, it is a kind of success, but we are not 100% happy.”

Altherr added the main reason a full ban was not put into place was because of opposition from the EU, which has accounted for 50-80% of the total mako catch in the North Atlantic since 2000.

Sonja Fordham of Shark Advocates International also said she was pleased with the full retention ban, but “mindful that the two-year time horizon is wholly inadequate for rebuilding this depleted and still declining population.”

“We will keep fighting to extend the ban long-term to give the makos the break they need to recover,” Fordham told Mongabay in an email, “while also pressing for additional measures to maximize the survival of makos caught incidentally and released.”

Banner image caption: Mako shark. Image by Steve de Neef for WCS.

Correction (11/26/2021): A previous version of this article contained a slight inaccuracy regarding the rules around the landing of mako sharks after the lapse of the ban. The article has been modified to say that fishing nations will only be able to land mako sharks if the total mako bycatch from the previous year does not exceed 250 metric tons.

Elizabeth Claire Alberts is a staff writer for Mongabay. Follow her on Twitter @ECAlberts.

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