Through the large mesh openings of conventional trawls, big amounts of bycatch and fish of unwanted size reach the ship, these are usually thrown dead overboard. The selection is a challenge. Inaccurate information of bycatch and catch quota complicate the calculation to make precise catch quotas. This puts fish stocks at further risk. It raises the question: How much fish can be caught and how much fish is still in the sea? A genetic modification (Fisheries-Induced Evolution) is caused by the fishing out of large individuals. The fish have gotten smaller and produce less spawn.
The Concept "Glaucus" is the result of my master's thesis, it has the potential for further development to avoid overfishing of fish stocks in the future.
Glaucus, an autonomous net, sustainably manages fish stocks, controlled by and connected with a monitoring system. It is equipped with the latest sonar and sensor technology and so it selectively catches fish. During the fishing process it is decided which fish are allowed to be caught. The special feature of Glaucus is the selection of the different sizes of fish using variable mesh openings. If the by-catch is too large or the fish do not have the appropriate size, the process is interrupted and the fish are released. Sustainable management of fish stocks is achieved by networking with the monitoring system, it determines stock size. This allows fishing quotas to be calculated precisely and overfishing is avoided.