Blowfly larvae in stockfish

Blowflies cause considerable damage on stockfish produced in Lofoten. The insects infest 5-10% of the production each year. This results in reduced quality and reduced prices. The amount of stockfish produced is large, and the product is very important as an export goods. Each year, the producers in Lofoten loose 7-20 million NOK due to blowflies. Despite the large loss, there have been few attempts to research and solve this problem. The blowflies lay eggs on fish in early spring while they are still mo ist. The larvae develop inside the fish, and then leave their food source to pupate in the ground. We will develop and test methods to attract and trap adult blowflies and larvae. We will also investigate the life cycle and the population growth potential of the major destructive blowfly species. The trapping program will be carried out in the production areas and it will be continuously refined and improved as the project proceeds. Fly density and stockfish damage will be monitored throughout the project period. The stockfish production creates a foundation for unnatural large populations of blowflies, and we expect the largest damage reduction to occur in the last year of the project when the local fly populations are reduced through the continuous trap ping effort. This project will be important for the stockfish producers. It may ensure a higher quality in their products, increase profit and stimulate growth in the industry. There is a direct economical gain as well as a long-term effect through stabi lity in income and improved reputation among customers. We will perform a large part of the work at the production sites to ensure active participation from the producers. Information about results and control programs will reach all involved parties thro ugh international scientific publications and Tørfiskforums already established information channels, which include newsletters, workshops, seminars, magazines, internet and contacts in the local press.