Saving endangered freshwater species by retrieving ghost nets and industrial waste in Gabon
In the Nyanga Basin area (the Ramsar site of Setté Cama), National park rangers (ANPN), Fisheries brigade (DGPA) NGO staff (WWF) and Nyanga Basin area local community work to protect the habitat of endangered freshwater species.
From 1970 to 2012, about one third of all animal populations were reported to be threatened according to WWF’s Living Planet Index. Over half of these populations are declining. The most common threat to declining populations is the loss and degradation of habitat. Freshwater habitats – such as lakes, rivers and wetlands – are immensely important for life on Earth. Freshwater accounts for only 0.01 per cent of the world’s water and covers approximately 0.8 per cent of the Earth’s surface but provides a habitat for almost 10 per cent of the world’s known species. Several studies have found that species living in freshwater habitats are doing worse than land species.
The freshwater Living Planet Index substantiates this finding, showing that the abundance of populations monitored in the freshwater system has declined overall by 81 per cent between 1970 and 2012, with an average annual decline of 3.9 per cent.
Crocodiles, pythons, turtles and manatees threatened by ghost nets
In the Nyanga Basin area in Gabon, there are several threatened freshwater species such as African crocodiles (slender snouted crocodile, Nile crocodile and dwarf crocodile), African rock python, soft shell turtles (Nile soft shell turtle, Aubry’s soft shell turtle) and the West African manatee. These species can frequently be seen in Lake Mandza, Mbissi River and Nyanga River.
These freshwater species, which contribute to maintaining aquatic ecosystem, are threatened by ghost nets (abandoned gillnets) and water pollution (industrial waste). Annually, this freshwater ecosystem provides at least 1, 195, 950,000 XAF (about USD 2 M) by small fisheries and 797.3 tons of fish for more than 10’000 inhabitants.
These nets, which hang like walls in the water and catch all freshwater life, are still being used to supply fish to Gabon’s markets. In addition to these active nets, there are also countless lost or abandoned gillnets called "ghost nets” in the habitat of endangered species. An average of 200 by-catches are observed annually in these small-scale fisheries with an important catch of slender snouted crocodile. Moreover preliminary analysis of a recent study has indicated water pollution in the lake Mandza.
As part of WWF’s ongoing wetland conservation efforts we are cooperating in an effort to retrieve ghost nets from the habitat of threatened freshwater species alongside partners like the National Agency of National Parks, the Gamba Fisheries Brigade and local communities including local fishermen.
Knowing the lake Mandza, Mbissi River and Nyanga rivers, local communities support to locate and retrieve abandoned nets in the water. In some of the abandoned gillnets that were retrieved, 30 by-catches of catfish, three Tilapia and one Nile soft shell turtle have been found. Moreover industrial waste has also been retrieved from the water. A total of 5078.741 acres of rivers and lake have been successfully cleaned up during two days of river cleanup from November 8 to 9 2017.
This first river cleanup campaign has mobilized more than 20 people in the Nyanga Basin (in the Ramsar site of Setté Cama). Kema Kema, Freshwater and Marine Officer at WWF Gabon, said: ”It is necessary to repeat this river cleanup and lake campaign once a year to improve the ecological integrity of these rivers and contribute to stopping the degradation of the Ramsar site of Setté Cama” .