Cape Town - On World Fisheries Day, the World Wildlife Fund highlighted whale entanglements, which it says can be greatly reduced if trap fisheries, often used for catching rock lobster and octopus, implemented rope-less fishing techniques.
The WWF-funded study by UCT researcher Michael Daniel and associate professor Colin Attwood put a number of techniques to the test which showed the ropeless fishing technique was a viable solution to reducing whale entanglements in South Africa.
”Whales often get entangled in the rope-based fishing gear of rock lobster and the experimental octopus fisheries. About R10 000 is spent on waste management services for every whale that dies from an entanglement and an average of 14 whale entanglements from various types of fishing gear was recorded every year for the past five years,” said WWF South Africa marine scientist Monica Stassen.
The UCT researchers said the ropeless fishing devices allowed for traps to be deployed in waters without a surface buoy indicating their position, the buoy was instead only released when the time came for harvesting, avoiding the risk of ropes floating in the water for long periods of time.
“In South African waters, Bryde’s whales are particularly vulnerable to entanglement in trap fishing ropes as they dive deep and fast to catch their food. Other species at risk include Southern Right and Humpback whales due to their natural tendencies to investigate floating objects like rope and kelp,” said Stassen.
Looking at the changes fishers would have to make to employ this technique, the researchers found that the appropriate ropeless fishing techniques would be economically feasible for all trap fisheries in South Africa and estimated an increase in costs of less than 5%.
Attesting to the success of ropeless fishing, Stassen said following concerns over entanglements which resulted in whale deaths in 2019, the Department of Forestry, Fisheries and Environment placed a temporary ban on the experimental octopus fishery in False Bay, after which the fishery started using ropeless fishing techniques and has not had a whale entanglement since.
With World Fisheries Day drawing attention to the importance of healthy oceans ecosystems and ensuring sustainable stocks of fisheries, CapeNature appealed to the public to practice responsible and safe fishing this summer.
“Legal and responsible fishing is everyone’s responsibility. Angling licences are a way in which fishers can assist in giving back to their favourite natural places and support the continuation of important conservation work.
“They further allow for the protection of our fish stocks and fisheries by regulating the industry,” said CapeNature chief executive officer Razeena Omar.