Almost as soon as the fishermen arrive with their haul, it disappears. The fish market in Epe, at the edge of Lagos, now runs like a kind of seafood cabal, with demand so high that many miss out. The major buyers are served as a priority – the big Lagos restaurants, a few cold room owners, then the rest. Sometimes smaller fishermen will sell to favoured market-stall holders. There is simply not enough to go around.

“When I couldn’t find red snappers in Victoria Island, a friend suggested I go to the Epe market. But the snappers were not there either, says Enita Aderemi, a local freelance writer. “The freshwater catfish I found cost three times the price I bought them for three months ago, a price that was already high.

The one-hour drive from her home to Epe is now a regular fixture in Aderemi’s life as she searches for seafood amid the rising prices and demand for fish in Nigeria’s largest city.

Nigeria is Africa’s largest importer of foreign fish, with a demand for more than 3m metric tonnes each year. Despite having an Atlantic coastline of 853km (530 miles), the country is unable to provide fish for a population that is predicted to double by 2050.

In Lagos, and particularly in Epe, fishermen and farmers are having to travel further to get fish. The Lekki lagoon, previously a fisherman’s paradise, is being slowly depleted by various megacity projects, the biggest of which is an oil refinery owned by Africa’s richest man, Aliko Dangote.

The Dangote refinery in the Lekki free trade zone, which is partially on the lagoon, lies on roughly 2,500 hectares (6,177 acres) of swampland. It is hoped that it will process 650,000 barrels of oil a day when completed, becoming Africa’s biggest such installation.

Nigeria currently exports all its oil as crude and then reimports refined petroleum products for use inside the country. The $12bn (£9.3bn) refinery is expected to eliminate Nigeria’s dependence on imported petroleum products, in turn lowering demand for foreign exchange, which the government says is a contributor to economic problems.

However, nearby coastal towns and communities are seeing a change in their local ecosystems. “The dredging of the coast to sand fill the lagoon for the construction of the refinery made the fish in the area disappear. We had to travel far into the ocean to get fish, but even that became dangerous because the waves became unpredictable, explains former fisherman Ayo Falade.

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