Aggressive Seals Brain Damaged From Toxic Fish Keep Attacking Bathers on Popular Beach

“Keep your distance, don’t go near it, don’t engage it.”

Experts believe the aggressive seals attacking people on Cape Town beaches are suffering from brain damage caused by consuming fish laced with toxic algae. Earlier this month, a crazed seal mauled a young boy before attacking an HBO actress who ended up in hospital with her injuries. Another woman was the victim of an unprovoked seal attack at a different beach, while a spear fisherman on the Cape Peninsula says a rabid seal tried to drag him into deep water.

"The animals that survive domoic acid poisoning suffer neurological damage and we suspect that is what has led to us seeing an increase in the number of attacks around Cape Town," Brett Glasby, from Cape Town's Two Oceans Aquarium, tells the UK Times. Here's what experts think is to blame.

No Fear

Cape Town Wild/YouTube

Video footage shows a seal attacking a boy at Clifton, Cape Town, utterly unafraid of the humans around it—one of the symptoms of brain damage. "The seal kept coming back… it came in and out the water, attacking the people on the beach. Eventually the lifeguards formed a circle around the seal to stop people from getting too close. After about 20 minutes, it swam out and we didn't see it again," eyewitness Biase De Gregorio told Daily Maverick. "It was kind of scary. It started off quite cute, but then turned a little bit hectic."


Cape Town Wild/YouTube

Officials at Hout Bay Seal Rescue Centre believe the seal was provoked by the beachgoers surrounding it. "Any predator that is surrounded and harassed like the seal was would have reacted the same way, but of course, the video doesn't show the part where the seal is being stressed by a crowd of people surrounding it," Dune Spence-Ross told News24.

"Yesterday, the beachgoers were lucky… it was only a yearling approximately 12 months old, weighing no more than 10kg (22lbs) by the looks of it. If that was a fully grown seal, the headlines would have been very different."

It's Poisoning


Glasby believes the seals are not deliberately being aggressive. "It's not aggressive behavior… it's defensive behavior. Last year, we had a mass die-off on our coastlines that was attributed to domoic acid poisoning from red tide algae bloom. The seals consume fish and crustaceans that have algae bloom domoic poisoning… one of the symptoms is a swelling of the brain.

The animals that survive domoic acid poisoning suffer neurological damage and we suspect that is what has led to us seeing an increase in the number of attacks around Cape Town."

Keep Away


Glasby warns beachgoers to stay away from seals, deranged or otherwise. "Everyone needs to know that seals are wild animals. Keep your distance, don't go near it, don't engage it, and contact the experts."

Official Warning


"Residents are reminded to keep their distance from marine mammals and to not interfere with them," says Alderman Eddie Andrews, Cape Town City's Deputy Mayor and Mayoral Committee Member for Spatial Planning and Environment. "Residents and visitors are encouraged to treat all marine and coastal wildlife with respect and to remove their pets from areas where wildlife may be present. In the interest of the safety of beach users, as well as the animals, I want to kindly request residents and visitors to keep a safe and respectful distance from these animals."

Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more
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