The abundance of juvenile flounder and turbot was surveyed in the VELMU and MARMONI-projects in years 2010-2014 in the Finnish SW-coast at altogether 103 sampling sites, almost all being located on sandy-bottom shores. Surveyes were conducted both on spring (for overwintered 1+ juveniles) and autumn (for young-of-the-year 0+ juveniles). Beach seine was the main survey method, but in year 2010 also a pushnet was tested. As by-catch also information of the occurrence of e.g. cyprinids, gobies and sticklebacks was gathered. Survey data has been used for developing an indicator describing the ecological status of the northern Baltic Sea and it is suitable for coastal spatial planning. ## Method description The abundance of juvenile flounder and turbot was surveyed in the VELMU and MARMONI-projects in years 2010-2014 in the Finnish SW-coast at altogether 103 sampling sites, almost all being located on sandy-bottom shores. Surveyes wereconducted both on spring (for overwintered 1+ juveniles) and autumn (for young-of-the-year 0+ juveniles). Beach seine was the main survey method, but in year 2010 also a pushnet was tested. As by-catch also information of the occurrence of e.g. cyprinids, gobies and sticklebacks was gathered.

2022