Two current shark assaults on a seashore in Florida led to a flood of social media rumors linking the instances to the presence of orcas within the Gulf of Mexico. However this “does not make any sense,” marine biologist Jesús Erick Higuera-Rivas, instructed Stay Science.
On June 7, three people were injured in two shark attacks off the coast of Walton County, between Destin and Panama Metropolis Seashore. Victims included a 45-year-old girl who was bitten close to Watersound Seashore, in addition to two youngsters who have been injured later the identical day, round 4 miles east of the primary assault.
The identical bull shark (Carcharhinus leucas) was probably answerable for all three assaults, Walton County Sheriff’s Workplace consultant Corey Dobridnia told USA Today.
Latest sightings of orcas (Orcinus orca) in the identical area led some folks to take a position that the killer whales have been driving bull sharks nearer to the shore, the place they have been attacking folks. Orcas had been seen on June 4 just south of Destin, about 75 miles (120 kilometers) from the place the shark assaults occurred.
Nevertheless, Higuera-Rivas says that the 2 occasions are “not related.” Higuera-Rivas research orca conduct on the Pelagic Safety and Conservation Civil Affiliation in Mexico, together with their interactions with sharks and rays.
Associated: Orcas are learning terrifying new behaviors. Are they getting smarter?
Regardless of observations of some orcas hunting great white sharks (Carcharodon carcharias) off the coast of South Africa and pursuing bull sharks within the Gulf of California, Higuera-Rivas says that the newest assaults are extra probably as a result of improve in human exercise close to the place bull sharks feed close to shore.
Get the world’s most fascinating discoveries delivered straight to your inbox.
Equally, the sightings of orcas within the area are additionally as a result of rise in eco-tourism. “You see extra pictures on-line about orcas being in [the Gulf of Mexico], however it’s not as a result of the orcas are showing increasingly more usually,” he stated. Reasonably, they’re simply being observed extra.
As a result of orcas have most likely at all times been within the area, however are solely now being photographed extra, Higuera-Rivas believes the Florida assaults are unlikely attributable to their presence.
Gavin Naylor, the Director of the Florida Program for Shark Analysis on the College of Florida, additionally agrees.
Naylor instructed Stay Science that orcas typically goal sharks, however this tends to occur fairly far off-shore. “There are such a lot of locations for sharks to cover away from orcas alongside the coast,” he stated, including that it is unclear why the sharks could be pushed to human-populated coasts, particularly. It appears particularly unlikely that bull sharks would accumulate close to the shore attributable to orca exercise as a result of the sharks even have the flexibility to cover in freshwater ecosystems.
As a substitute, Naylor means that the bull shark attacks are probably as a result of bait fish transferring nearer to the shore, thus drawing the sharks in.
Latest sizzling, dry climate in Florida might imply that freshwater output from estuaries has fallen. “When there’s much less estuarine output, then the saltwater can come nearer to the shore than it might usually do, and that brings with it the plankton and the bait fish that eat them,” he stated.
With the bait fish come the bull sharks, Naylor stated.