Rapport nr 123: Uppföljning av kräftbestånden i fyra Åländska sjöar 2008
PERSSON, J (2009)
PERSSON, J
Åbo Akademi, Husö biologiska station
2009
Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden.
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
Julkaisun pysyvä osoite on
https://urn.fi/URN:ISBN:978-952-12-2248-1
https://urn.fi/URN:ISBN:978-952-12-2248-1
Tiivistelmä
A follow up study in order to monitor the crayfish populations was carried out throughout the summer of 2008 in the lakes Markusbölefjärden, Långsjön, Östra Kyrksundet and Västra Kyrksundet in the Åland Islands. The Lakes Markusbölefjärden and Långsjön had a high catch per unit effort, and the crayfishes were also fairly large. Östra Kyrksundet and Västra Kyrksundet had a much lower catch per unit effort and also a much lower average length of the crayfishes. The highest number of crayfish caught was in the month of September. Markusbölefjärden, Långsjön and Västra Kyrksundet had a higher catch per unit effort 2008 compared to 2007, but the crayfishes were on average smaller. The opposite pattern was found in Östra Kyrksundet with fewer but larger crayfishes 2008 compared to 2007. The overall results of the crayfish monitoring 2008 coincide with what was expected according to the crayfish monitoring conducted in 2007.