WATCH | Seal pup attacks swimmers at Clifton Beach in Cape Town

An aggressive seal pup attacked two swimmers at Clifton Beach on Tuesday, the latest in a spate of similar incidents that have prompted the City of Cape Town to caution beachgoers about marine wildlife.

A video of the latest incident circulating on social media shows the seal lunging at a swimmer, who was subsequently treated by lifeguards. In the video beachgoers express delight at the sight of the seal in the surf with bathers, but the voice-over quickly changes to horrified screams as the seal begins to bite people in the shallows. Lifeguards can be seen rushing to swimmers' assistance and trying to clear the water.

City coastal manager Gregg Oelofse confirmed the incident and said lifeguards are monitoring the situation in case the seal returns, in which case it may be removed. 

“It is unusual behaviour, to see it target people in the water. But it could be that the seal is under stress and pressure,” he said, adding that the beach was crowded at the time.

“Mostly seals will avoid conflict so the incident is a bit unusual, but we are not sure how much pressure it was under.”

He warned beachgoers to give otters and seals a wide berth. An otter recently also made headlines for playfully nipping several swimmers at Dalebrook tidal pool in Kalk Bay. The bites were not aggressive but had to be treated and caused concern. 

Two people were injured under similar circumstances at Fish Hoek Beach late last year.

The incidents have prompted widespread debate about the possible impact of a biotoxin linked to algal blooms in the water. Marine mammals are known to have suffered neurological damage due to exposure to these algal blooms which contaminate sea life that form part of seals’ diet. An increase in algal blooms has been linked to increased sewage run-off.  

However, Oelofse said it was too soon to say whether the latest incidents were linked to the biotoxin, known as domoic acid. Various possible other factors could be at play, he said.

Last year TimesLIVE reported on evidence presented by Dr Tess Gridley, founding director of Cape Town research group Sea Search, who said seal aggression could be linked to an increase in domoic acid linked to algal blooms.

To date domoic acid has been found in one or more seals from 13 different locations — from Lamberts Bay on the West Coast to Muizenberg in Cape Town, Gridley said.

The toxin was found in seals all ages and both sexes of animals tested. “It is one potential explanation for this sudden change in behaviour. We obviously want to check this line of inquiry,” she said, adding that reports of seals chasing people on land were highly unusual.

A video circulating on social media showing one of last weekend’s attacks shows the seal pursing a startled woman across Fish Hoek Beach and then pouncing on her. “It is very unusual for an animal to come out of the water and purposely chase a person — it is very unusual and doesn’t make sense,” Gridley told TimesLIVE.

The National Sea Rescue Institute (NSRI) on Wednesday said other seal incidents had been reported in Hout Bay and Yzerfontein earlier this week.

“We appeal to bathers and paddlers to stay clear of seals and avoid marine animals in their environment,” it said.

NSRI CEO Cleeve Robertson advised people bitten by a seal to seek immediate medical attention at their doctor or a hospital emergency room.

Bite wounds from seals become severely infected and require thorough cleaning. Wounds of this nature should not immediately be stitched and the patient should be prescribed broad-spectrum antibiotics.

TimesLIVE

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