NEWS AND COMMENT-CAPE TOWN: As I understand this, this is a disturbing example of humankind’s effect on wild animal behaviour through their behaviour. That is not how the story is presented but it is how I read the story.
Along the coast off Cape Town, South Africa, historically the toxic algal bloom lasts only a few weeks. Under those circumstances, I believe, nothing much happens because it comes and goes.
The video comes from the thesicilianwifey on TikTok [link]. The video is downloadable and I have shortened it to make it more manageable. The message is clear: extremely abnormal behavior.
However, it is believed that the waters have been warmed by climate change and pollution which has resulted in the rust-coloured toxic blooms known as red tide becoming much bigger and lasting for much longer. Scientists have confirmed that global warming is due to human activity although the point is still debated.
And because this toxic algae is in the water for much longer than normal, it is having a severely detrimental effect upon marine life including seals.
It is further believed that these unprovoked aggressive attacks by what we consider normally to be fairly benign sea creatures, are due to a neurotoxin produced by marine algae accumulating in crustaceans, small fish and squid which are then eaten by predators.
And once inside predators like the seal, it causes severe brain damage which dramatically affects their personality and which in turn drives them to attack beachgoers on the seashore as we see in the video.
Normally, seals are not dangerous to humans, and neither are they friendly to humans. They are nervous of humans as I understand their normal behaviour. So, this is a great departure from the norm.
It is also of course very disturbing. Incidentally, I don’t like the way a macho man shows off their prowess to the women when he grabs the seal by a flipper and chucks it back into the sea after hanging onto it for a considerable time. That to me it is distasteful. After all, it is humans who indirectly are the cause of this abnormal behaviour although of course he probably didn’t know it at the time.
The attacks have been against several people one of which occurred at a different beach on the Cape Peninsula. Another attack was against a spear fisherman who said that the seal tried to drag him into the sea.
These attacks have increased since a large number of seals died along the coast due, it is believed, to poisoning by domoic acid. As I understand it, this is the same chemical which causes brain damage and which is also produced by marine algae.
The seals that have attacks people are the ones who survived this neurotoxin.
Below are some more articles on marine wildlife.