Bycatch – can a WWF competition solve one of global fishing’s biggest problems?
Bycatch, if you’ve never come across the term, relates to the marine life (usually fish, birds and mammals but some include corals, sea stars and even jellyfish) inadvertently caught by fishing boats who are targeting sellable fish.
Within the basic principles of the quota system, a commercial fishing operator with a license to catch 20 tonnes of pilchards would not be able to haul in and keep 1 tonne of mackerel – so they have to throw back the unwanted catch, which are mostly dead. This obviously depends on the laws of their country and/or their ship’s flagged country – which is a whole other kettle of fish…
World Wildlife Fund for Nature lists some of the damage caused by commercial fisheries when it comes to bycatch. I’ve seen arguments disputing the types of numbers below but no one can say that it still isn’t a huge issue for governments, environmental bodies and fisheries to do something about:
- Over 300,000 small whales, dolphins, and porpoises die from entanglement in fishing nets each year, making bycatch the single largest cause of mortality for small cetaceans and pushing several species to the verge of extinction.
- 89% of hammerhead sharks and 80 per cent of thresher and white sharks have disappeared from the Northeast Atlantic Ocean in the last 18 years, largely due to bycatch.
Scary. WWF must then be congratulated for putting money into a competition for tools to help eliminate bycatch and some of the winning designs so far have been impressive at least in concept stage:
- A net designed to reduce the bycatch of cod while still allowing for the capture of species such as haddock
- “Underwater baited hooks” designed to reduce the capture of seabirds on longlines
- A concept that used magnets to repel sharks from longline areas, as many sharks are sensitive to magnetic fields
- A mechanism to set hooks below 100m to reduce the catch of turtles and other non-target species
Convincing large commercial operations to invest in these devices is the hard part. Seeing as the website doesn’t seem to have been updated since late 2011 – possibly due to the next competition not being held until 2013 for some reason – it’s hard to gauge whether any of the winning devices have been successfully introduced into commercial fisheries.
But then, turtle excluder devices were probably seen as unnecessary by the industry early in their development and now they are a common fixture worldwide in the prawn industry. And that device was invented in the 1970s by a US fisherman….