/ 22 November 2021

Ropeless fishing reduces whale entanglements, UCT study finds

Continued pressure on fish stocks caused by poor law enforcement
File photo

The use of ropeless techniques by fisheries greatly reduces the risk of whales getting entangled, a new study conducted by researchers at the University of Cape Town (UCT) has found.

Bryde’s whales, which can be found in South African waters, are particularly vulnerable to entanglements in trap fishing ropes because of their ability to dive deep and fast to catch their food. Such entanglements can sometimes result in drowning, but new technology could prevent them from occurring.

The World-Wide Fund for Nature (WWF)-funded study, the first of its kind in South Africa, examined the use of ropeless fishing devices, which remove the need for floating ropes between the water surface and ocean floor. These devices allow traps to be deployed in waters without a surface buoy indicating their position. 

“We specifically looked at the whales because they are the ones that get trapped in these ropes,” said Colin Attwood, an associate professor at UCT. The researchers found that the appropriate ropeless fishing techniques would increase costs by less than 5%, making them economically feasible for fisheries. However, the researchers will continue to focus on the technology’s financial viability. 

“Future research will look at the financial viability of the equipment because it is quite expensive. There might be some resistance from the fishing industry so it will be important for us to work with them [the fishing industry] so that we can save the whales.”

Other whale species that face the risk of being entangled include the southern right and humpback whales because of their natural tendency to investigate floating objects like rope and kelp.

An octopus fishery in False Bay has been using ropeless technology since the beginning of 2020 and has not had any whale entanglements since then.