Local communities in the Eastern Cape have been left dumbfounded for the best part of the month, after scores of unusual fish species – ranging from sharks to manta rays – washed up on coastlines including Morgan’s Bay and Kidd’s Beach.
Photo: SAAMBR
Exotic fish washing up in the Eastern Cape – but why?
Plenty of creatures, ranging from the great and small to the wonderful and weird, have sadly been beached and left to die. In an unfortunate turn of events, something of a ‘feeding frenzy’ has taken place on a few shorelines, as fishermen and market traders rush to secure the easiest catches they’ll ever make.
But those buying from their favoured outlets might notice something different on the menu: The lesser-spotted Carcharhinus, certain species of catfish, and even the odd pufferfish have all been reported on the sands. So, what exactly is causing this strange phenomenon? The SA Association for Marine Biological Research (SAAMBR) gave us the answers.
Photo: SAAMBR
Cause of deaths revealed
According to the marine experts, A massive drop in temperature reported just last week off the Wild Coast is to blame. This so-called ‘sea shock’ saw water temperatures plummet by a whopping 12°C in one day – catching many of these exotic fish off-guard. Strong winds and significant changes to weather patterns are the main drivers of these conditions.
“Many people are asking why so many fish and sharks died along the Wild Coast. It would appear that they died from temperature shock as the sea temperature dropped from 26°C to 14°C overnight, Well, the coastline is generally not straight, and the numerous headlands and bays cause further changes in inshore water movement patterns.”
“In cases of prolonged strong north-easterly winds (as was experienced last week), the ‘thermocline’ – a steep temperature gradient between two bodies of water with warmer water above and cooler water below – comes to the surface and causes a sudden drop in surface water temperature and in severe cases can stun and even kill fish.”
As revealed by marine analysts at the East London Museum, these are the latest species washing up on shore:
– A number of sharks were investigated this past weekend.
– A 3.1m Dusky Shark from Gulu has since washed up on shore.
– Also, a 2.1 m Carcharhinus species from Kidd’s Beach soon followed.
– A live manta ray was reported from Haga-Haga last week, as was a slightly smaller ray.
– Many of the fish that were killed are known as ‘local catches’ – but the high number of exotic fish raised concerns.
– They showed no signs of physical trauma and the deaths are associated with the recent sea temperature drop.
Photo: SAAMBR
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