In an extraordinary discovery that challenges scientific expectations, marine biologists have confirmed the first known case of a whale shark not only surviving but thriving with a severe spinal deformity. The remarkable 20-foot animal continues to exhibit normal behavioural patterns despite its significant physical impairment.
A Rare Encounter in the Gulf
The unique whale shark was first sighted by researchers back in 2010 at Ewing Bank, off the Louisiana coast in the Gulf of Mexico. The team, led by Eric Hoffmayer, a 50-year-old research fisheries biologist with the National Marine Fisheries Service, recently encountered the same individual again, prompting a deeper investigation into its survival.
'To see such a large animal surviving with a spinal deformity like that is extremely rare,' Hoffmayer stated. 'Typically, those types of deformities are not compatible with life. Usually, you see more examples of it in embryonic animals.'
Unlocking Secrets with Satellite Technology
Intrigued by the double sighting, the scientists decided to fit the shark with a satellite tag to monitor its movements. 'We actually put a satellite tag on it and figured, well, let’s learn more about this animal since it’s unique that we’ve encountered it twice now,' Hoffmayer explained.
The data collected revealed astonishing insights. Despite its obvious swimming difficulties, the shark's daily routines were largely unaffected. Its swimming speeds, preferred water temperatures, and depth choices all aligned with those of healthy, non-deformed whale sharks tagged in the same region.
'What was really interesting was... everything seemed to fall in line with the other sharks that we tagged in the region that didn’t have the spinal deformity,' Hoffmayer noted.
The Key to Survival: A Gentle Diet
Researchers believe the whale shark's specific feeding strategy is the crucial factor behind its unlikely survival. Unlike predatory sharks that must chase agile prey, whale sharks are gentle filter feeders. They swim slowly with their vast mouths open, consuming plankton and small fish from the water.
'Watching the animal swim, it obviously impacted its swimming, but because these animals feed on plankton, it still could maintain a certain swimming motion and speed,' Hoffmayer added. He emphasised that if it were a predator needing to catch fast prey, it would have struggled and likely not survived.
The evidence suggests the deformity was congenital (present from birth) rather than caused by an injury such as a boat strike. This makes its long-term survival even more remarkable. 'This animal’s got this deformity, but it’s been able to overcome it and still maintain its normal behaviour and feeding habits,' Hoffmayer concluded. 'It’s been able to overcome this spinal deformity and still do the everyday things that whale sharks do, which is really remarkable.'
