How does waste feature in the world’s fishing industry? Wasted fish, in the fish industry, is called by-catch. By-catch is the term used to describe fish that are caught and often discarded (but not always). It is fish that harvesters are not allowed to catch for licencing reasons, or fish that cannot be sold for a high price. By-catch is widely regarded as an environmental crisis as it depletes ocean resources and destroys marine habitats.
The global shrimp industry has been one of the biggest culprits of by-catch. In some parts of the world it is estimated that 9 pounds of fish are caught and then discarded for every 1 pound of shrimp that is retained. While the shrimp industry is often cited as the most serious offender when it comes to by-catch, it is also the industry that has developed the most innovative devices to reduce by-catch through what are called ‘excluder devices’. These pieces of technology are added to existing trawl systems and allow fish and other animals to escape the nets before being captured. The development of the technology usually involves extensive experimentation and collaborative work between harvesters and fisheries scientists. In some cases the devices have reduced by-catch to negligible levels. Harvesters that use excluder devices have often found it easier to have their industries certified as sustainable, which is an added incentive to use this technology.
The wasted fish project is just underway, and the focus now is on what is probably the most famous of all excluder devices, the Nordmore grid. This excluder device was developed in Norway and then exported to Newfoundland, Nova Scotia, the Gulf of Maine and other parts of the world. There is a fully funded MA position associated with this project – if you are interested, please contact me (firstname.lastname@example.org).
NEW: There’s been an interesting breakthrough in excluder devices developed for Oregon’s pink shrimp fishery. By lighting up the excluder device, they’ve been able to further improve the efficiency of the device.