Summary: | In the summer of 2006 Föglö was investigated as the second survey area in the long term project of fish stock survey on Åland. Seining for juvenile fish and adult smallsized fish species were performed on Föglö and in responding areas of Geta and Eckerö. Test-fishing for larger adult fish species were performed on Föglö and in the responding areas of Finbo and Kumlinge. Seining for juvenile flounder and turbot were done across the mainland of Åland. The purpose was to investigate the status and recruitment ability of the fish stock on Föglö in comparison to reference areas. Perch was the most common species in the test-fishing and occurred frequently on all depth strata, although the recruitment of perch on Föglö seems poorer than in the reference areas. Cyprinids were also common in the test-fishing, which might indicate eutrofication. Diminishing pike populations on Föglö have previously been of great concern. The pike catches in this investigation were however no lesser than in the reference areas. In the seinings for warm water species mostly three-spined stickleback and nine-spined stickleback were caught on Föglö and three-spined stickleback and goby in the responding areas. In the seinings for flounder and turbot juveniles only few individuals were caught on Föglö in contrast to the responding areas where they were caught more frequently. Cladophora spp. was exctensively present on Föglö and probably affected negatively both perch, pike, flounder and turbot juveniles. Both the high number of perch and cyprinides and the overgrown bottoms indicate eutrofication on Föglö. Generally species of commersal interest were caught in low numbers on Föglö in the test-fishing, except for perch, and the recruitment of theese species were also poorer on Föglö than in the responding areas.
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