Washed-ashore fishes: Regular ocean monitoring programme must be established – UG Marine Dep’t

The Department of Marine and Fisheries Sciences, University of Ghana, has called for the establishment of an ocean monitoring programme in the country to urgently study trends in sea surface temperature across Ghana’s coast.

In a preliminary assessment of the recent dead fishes and dolphins at some beaches along the coast of Ghana, the Department observed that Chemical Oxygen Demand (COD) in the sea was significantly higher than expected.

“This oxygen demand would most likely create a condition of stress on living organisms that depend on dissolved oxygen in the water body,” part of a release dated Sunday, April 11, 2021.

Sea surface temperature

The press release added that sea surface temperature over the coast from Côte d’Ivoire to Togo dropped in few days to the fish kills.

They, however, could not indicate the factors that caused such incidents.

“This is most likely an indication of upwelled water from the bottom of the ocean, probably carrying low oxygen concentration. At this stage, we do not have any data on what triggered these incidents."

“It requires that an ocean monitoring programme is established as a matter of urgency,” they suggested.

Possibility of Phytoplankton abundance

The preliminary assessment did not observe any possibility of incidence of harmful bloom in the sea.

This is because there was no phytoplankton abundance needed to cause a bloom.

Though species of phytoplankton are said to be present in waters, “their higher than normal levels could lead to a situation of harmful bloom.”

<>Identification of marine mammals and fish species

The University of Ghana’s Department of Marine and Fisheries Sciences identified the dead marine mammals as the melon-headed whale (Peponocephala electrica), a dolphin belonging to the Cetacean order.

Meanwhile, “the fish species that were killed were both demersal (bottom-dwellers), and pelagic (above bottom-dwellers); of both small and large

sizes.”

Impact of global climate change on coastal states

The researchers have highlighted the need for Ghana to get research vessels that can help to embark on regular monitoring of coastal waters.

They also want urgent attention to be paid to marine living and non-living resources to augment the country’s national wealth.

“The impact of global climate change and its vulnerability is real and coastal states are the worst to be affected,” the release noted.