Experts stunned after spotting rare shark species off coast of major city: 'We haven't had this sighting before'

A shortfin mako shark was spotted for the first time in the urban waters of Rio de Janeiro's Ipanema Beach in late March.

The Pinnacle Gazette reported that footage was captured by Andrew Macau, a diving instructor who was on the water with a group heading to the Cagarras Islands.

"I've been scuba diving for over 10 years, working and doing many dives every week, and we haven't had this sighting before," Macau told Reuters, in translation.

Macau also told The Pinnacle Gazette that guided mako shark dives can cost up to 6,000 Brazilian reais, which is about $1,030. This was a rare and valuable experience, bringing joy to researchers and everyday citizens alike.

Sources conflict regarding the classification of shortfin mako sharks as an endangered species. The National Oceanic and Atmospheric Administration Fisheries determined in November 2022 that the species should not be listed under the Endangered Species Act.

Shortfin mako sharks are, however, on the International Union for Conservation of Nature's endangered list, according to Nova Southeastern University Newsroom. This is because of the international demand for shortfin mako shark meat and fins.

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While U.S. legislation bars fisheries from capturing the shortfin mako shark, scientists remain concerned about its status.

Researchers at the Save Our Seas Foundation Shark Research Center and the Guy Harvey Institute at NSU looked into the sharks' genetics for a solution. They eventually sequenced entire genomes for mitochondrial DNA in Northern and Southern Atlantic shortfin mako sharks.

"Despite decades of fishing pressure, shortfin mako sharks in the Atlantic Ocean still show (relatively) high level of genetic diversity," professor Mahmood Shivji told NSU Newsroom. "Genetic diversity in a population is what allows species to adapt to environmental change, or to survive catastrophes."

As long as shortfin mako sharks continue to move around frequently, which should be possible considering their nomadic tendencies, it is highly likely that their genetic diversity will help them survive despite overfishing. Reducing overfishing will also ensure that we can fish from the ocean for as long as possible.