Ecosystems of great biodiversity, the coral reefs of Fernando de Noronha and the archipelago of São Pedro and São Paulo, two sets of Brazilian oceanic islands, face the threat of plastic waste and abandoned fishing gear. A study published in July this year revealed that these two reef environments are among those with the highest amount of trash, alongside reefs in Comoros (West Africa) and the Philippines.
“We dived in these places, thinking we were going to explore a completely unknown environment, but, in fact, there was already evidence of human impact in these regions, with a lot of trash and fishing material”, revealed researcher Hudson Pinheiro, from the University of São Paulo. (USP) and the Network of Nature Conservation Specialists (RECN), maintained by Fundação Boticário.
According to the researcher, both plastic and abandoned fishing material are risks to marine life. In the case of plastic, for example, animals can mistake it for food and suffocate or become poisoned by the material.
In the case of fishing waste, such as lines, nets and hooks, even at the bottom of the ocean, they continue to trap and kill marine animals. “It’s what we call ghost fishing. These equipment continue fishing for a while, causing an impact on the community. And, when a longline or a rope gets stuck in a reef, they pull and break the corals”, explains Pinheiro.
The researcher argues that it is necessary to rethink the use of plastic by society and also the use of biodegradable material by fishermen, so that this equipment, if abandoned at the bottom of the sea, does not continue to cause impacts on wildlife.
But it’s not just waste that threatens biodiversity in corals. According to Pinheiro, the discovery of this fishing trash in these reefs, far from the coast, reveals that there is great fishing activity in these areas.
“There is this tendency for fishing to go further and further to try to maintain the profit and profitability that they had. It exhausts the nearest resources [da costa] and they move away”, highlights Pinheiro. “There is a very common fishing characteristic in these environments. When fishermen find these areas [recifais, com grande riqueza de peixes]they manage to exhaust all commercial species.”
Hudson Pinheiro cites as an example some marine species that were common in Fernando de Noronha and São Pedro and São Paulo, but which were driven almost to extinction by fishing.
In Noronha, for example, in the 60s and 70s, there was overfishing of sea bream (Lutjanus purpureus), causing its disappearance in the area. Only recently have researchers found individuals of the species again.
In São Pedro and São Paulo, the fishermen’s targets were sharks. “In the 70s and early 80s, there was a very abundant population of local reef sharks there in São Pedro and São Paulo. And these sharks are no longer seen as they were. It seems like they are now recovering after the last 10 years. They banned shark fishing,” he said.
According to Hudson Pinheiro, these reefs are located far from the Brazilian continental coast. In the case of coastal reefs, which stretch from Bahia to Rio Grande do Norte, the impact of this trash is probably even greater. At the end of October, the Brazil Agency published a series of reports on the threats to coral reefs and the importance of these ecosystems for Brazilian cities and for the preservation of biodiversity.