Great White Shark Ironbound Returns to Florida Keys for Second Time in a Season: 'Not a Behavior We Often Track'

A great white shark known as Ironbound has returned to the waters around the Florida Keys for the second time in just a few months—a move that has puzzled researchers.

Last October, scientists from non-profit OCEARCH tagged the 12 foot, four-inch-long shark with a monitoring device in the waters off West Ironbound Island, Nova Scotia, Canada.

Since then, data indicates that the nearly-thousand-pound male has traveled more than 2,700 miles, a journey that has included two separate trips to the Florida Keys. According to OCEARCH, which collects data on shark movements, this type of behavior is not usually seen among the great whites they monitor.

"We know white sharks can be found in the Gulf of Mexico for more than six months out of the year so we know it is an important habitat for at least some white sharks in the Northwest Atlantic," Chris Fischer, OCEARCH's Founding Chairman and Expedition Leader, told Newsweek.

"We also know that white sharks can commonly be found there into April. In fact in 2018 we were tracking at least three white sharks in the Gulf of Mexico in late April. What is interesting about Ironbound's movements is that he already made it at least as far as Key West back in January, so to see him returning for a second time this season is not a behavior we often track," he said.

After spending time in the Gulf of Mexico, great white sharks in the waters surrounding North America tend to make their way to more northerly latitudes for the rest of the year, OCEARCH's data has revealed.

"The Gulf of Mexico is a highly productive area full of life that we suspect offers white sharks abundant opportunities for feeding," Fischer said. "We tend to see most of their activity focused along the edge of the continental shelf about 100 miles west of the Florida Gulf coast."

"As mentioned above, we often see white sharks hang around in the Gulf of Mexico through April. Sharks start to push north as the season changes and follow cooler water up north," he said.

According to Fischer, Ironbound was one of the trickiest sharks that the OCEARCH team has ever tried to catch and tag.

"Our Fishing Master Captain Brett McBride said that [this] was one of the toughest sharks he has seen, especially considering [its] size," Fischer previously told Newsweek. "At 12 foot, 4 inches and right about 1,000 pounds, [it] fought like some of the much bigger sharks we've encountered in places like Guadalupe Island, Mexico and South Africa that were 15 feet long or more."

ironbound great white shark
OCEARCH researchers measuring great white shark Ironbound. OCEARCH

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Aristos is a Newsweek science reporter with the London, U.K., bureau. He reports on science and health topics, including; animal, ... Read more

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