Divers spot sharks for science

Divers observe a reef shark on Grand Cayman’s East End. – PHOTO: STEVE BROADBELT, OCEAN FRONTIERS

Affectionate nicknames like Smudge, Scarlet and Big Bertha are not the first thing most people think of when they see a seven-foot shark cruise by.

But resident predators have become such familiar fixtures on Cayman Islands’ reefs, divers have begun to give them pet names.

“Burt and Ernie are usually found at one particular dive site. Smudge, Scarlet and Big Bertha at another area,” said John Buckley, a frequent diver at East End. “The sharks are inquisitive and will literally swim right up to you, swim amongst groups of divers, through tunnels, canyons, and come back around for more.”

Divers across the Cayman Islands are helping keep tabs on the islands’ shark population by logging sightings like these with the Department of Environment.

Since 2008, the department has partnered with Marine Conservation International to study Cayman’s sharks, and the data from divers is a useful tool for researchers.

“In 2017, the shark-loggers logged 9,615 dives and 1,880 shark sightings,” said Johanna Kohler, a marine scientist with the Department of Environment and program manager for the shark logging project.

“The information gathered complements the database from our surveys and acoustic tags,” she added.

Shark-loggers record shark sightings during a dive and note the location, time and species. The statistics show that Caribbean reef sharks and nurse sharks are the most common species spotted in Cayman waters. Other sharks spotted include tiger sharks, black tips and hammerheads, though they are rare.

Ms. Kohler said the information, from dive operators and their guests across all three Cayman Islands, was useful in determining the abundance of shark species in different areas, seasonal behavior patterns and the home ranges of individual sharks.

Steve Broadbelt, co-owner of Ocean Frontiers in East End, where reef sharks are commonly spotted, said divers enjoyed submitting photos and logging their sightings to help with the study.

He said, “Sharks top most divers’ wish lists when asked what they would like to see on a dive, and seeing one is always the highlight of their trip.”

James Dudley, of Tortuga Divers, also in East End, said divers recognized the importance of sharks to a healthy ecosystem and were keen to help.

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