It was the Shark Spotters, on their mountain vantage points, who first noticed that something was up. Or rather, down. A few years ago, they would regularly spot Great Whites and alert local bathing beaches. After all, there were several hundred known to be in the area and although humans were not their regular prey, there had been occasional attacks. But from 2019 no sharks were seen. And carcasses began washing up on-shore, intact but for the removal of their livers.
So... what was happening?
It was time to consider the possibility that False Bay's apex predator had been ousted by a bigger beast. Enter a pair of Orcas, or Killer Whales, seen cruising the waters. These ocean heavyweights (6 -10 tonners versus the 2.5 tons of Great Whites) have a particular love for liver, according to scientists. To sate their appetite, they are known to attack Great Whites via their pectoral fin and excise the nutritious liver. The pair in False Bay are now so notorious that they have been christened by locals as Port and Starboard, due to the particular slant of their dorsal fins. The appearance of the Orcas, the disappearance of the Great Whites and the shake-up of the food chain has left locals mystified; and is being studied by scientists to understand what it means for the seals (Great Whites' favourite prey) and those beneath them in the marine menu.
But are the Orcas entirely responsible for the disappearance of the Great Whites?
One theory is that the rise of small shark fishing in the bay has removed another of the Great Whites' target prey, and that this may have pushed them to move on to less contested waters. And why did the Orcas arrive in the first place? Did changing temperature and sea conditions bring them to False Bay where they just happened to stumble across convenient prey? And will they move on now that the source of tasty liver has disappeared?
Watch this watery space...
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