Horse mackerel trapped in rocky reef at Mile 8 – Ministry provides an explanation

Floris Steenkamp

The Ministry of Fisheries says the recent incident where horse mackerel (Trachurus capensis) washed ashore at Mile 8 was not caused by any environmental conditions. Predator fish and seals are believed to have pushed the shoal of horse mackerel into the shallow water causing the fish to be trapped in tidal pools and washing out on the beach.
In addition, the Ministry says in a statement the fact that people scooped up the fish for own consumption can-not make any dent in the country’s current horse mackerel biomass that is estimated at 36 billion individual fish. Putting the number into perspective, the press statement ex-plains the country’s current horse mackerel total allow-able catch (TAC) of 350 000 tons represents 7 billion individual fish.
“Before results from observatory scientific findings were concluded, we suspected that the following may have been the possible cause [of the fish washing ashore at Mile].
Environmental conditions, fish behaviours or local changes in the chemistry of the sea-water”, reads the statement.
Results from these observatory scientific findings eliminated environmental- and negative seawater conditions. Not even sulphur eruptions occurred in the area that deplete oxygen levels and forcing marine life into the shallows and even onto the beaches.
Satellite imagery sup-ported this finding and that prompted marine scientists to look for the possible cause in fish behaviours and providing a scenario as the possible solving to the riddle.
“It is therefore possible that fish behaviour led to the circumstance where-by a shoal of horse mackerel may have swum close to the shore during high tide, from where it was forced onto the rocks by marine predators. Some predator or predators, for example a group of seals or predatory fish, approaching from the deep may have chased the fish into the very shallows. The only possible escape route for the fish would have been in the direction of the shore causing them to end up where they were found when the tide dropped”, further reads the statement.
With regard to people then swarming the beaches to pick up fish and scoop fish from the water with any-thing that can hold fish, including shop-ping baskets, the ministry said there cannot be negative impact on the total horse mackerel bio-mass found in Namibia’s exclusive economic zone (EEZ).
The ministry further said there is no scientific basis to support the current believe and perspective on social media that the significant volumes of fish washed ashore. Not even a video clip, where the person filming the event says “fish as far as the eye can see”, can really serve as a basis to support the perception that the horse mackerel biomass was hurt by this event, it was explained.
The Ministry made it also clear though that it also finds event like this unfortunate, as it unpleasant to see any event of this kind occurring as fish is one of the pillars of our economy and we want to see our fish resources protected for posterity.