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Great White Sharks: New Findings Reveal Their Presence in the Bahamas

The waters surrounding the Bahamas are not commonly associated with sightings of great white sharks, yet a recent study published in Frontiers in Marine Science suggests these iconic predators visit more frequently than previously thought.

A research team analyzed five years of acoustic tracking data and discovered that at least 10 tagged great white sharks made nocturnal excursions into the deep waters of the region. These findings indicate a pattern of migration that has often gone unnoticed.

“The absence of sightings doesn’t imply they are not present,” noted Simon Dedman, a marine scientist with Florida International University and a co-author of the study. “The habitats that humans frequent may not coincide with those used by white sharks, which tend to explore deeper waters during the night as they move through the area.”

Great white sharks are vital apex predators that maintain ecological balance in marine environments. Although their numbers have significantly dwindled due to overfishing and bycatch, emerging research points to a promising recovery trend for white shark populations in the northwest Atlantic.

Notably, regions like Southeast Florida and the Gulf of Mexico act as crucial wintering habitats for maturing white sharks. Interestingly, despite the geographic closeness to Florida, a sweeping survey covering the years 1800 to 2010 recorded only a single sighting of a white shark in the Bahamas.

The researchers focused on acoustic tracking data from the years 2020 to 2024, monitoring these 10 sharks along the western boundary of the Tongue of the Ocean, a significant deep-sea basin near Central Andros Island. These creatures were primarily detected at the edge of the reef, approximately 25 meters deep, exclusively from dusk until dawn.

Out of the 10 sharks, seven were detected only once, while the remaining three were observed over several days. These sharks were initially tagged off the U.S. and Canadian coasts and were found in Bahamian waters mainly during the winter and spring seasons. The data suggests that these sightings represent transient movements rather than established residency.

The Bahamas has taken significant steps to protect shark populations, having prohibited commercial longlining and gillnetting since 1993 and designating its waters as a shark sanctuary in 2011. While these actions have made the region an essential haven for various shark species, data concerning the white shark remains sparse. The findings from this latest study contribute valuable insights into the distribution of white sharks along the Atlantic coast and underscore the need for joint conservation efforts to support the recovery of this species.

More information: T. L. Guttridge et al, First evidence of white sharks, Carcharodon carcharias, in the tongue of the ocean, central Bahamas, Frontiers in Marine Science (2024). DOI: 10.3389/fmars.2024.1451808

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phys.org