Rapport nr 113: Förekomst av adult fisk i grunda havsvikar på Åland
JÄRVINEN, M (2005)
JÄRVINEN, M
Åbo Akademi, Husö biologiska station
2005
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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:952-12-1638-7
https://urn.fi/URN:ISBN:952-12-1638-7
Tiivistelmä
Six shallow bays in the archipe/ago of NW and East Atand were studied on fish and fish migratory parameters on five occasions during late spring and summer (4-9.5, 23-28.5, 18-22. 7, 2-8.8 , 16- 19.8, 2004). The results showed, that the freshwater species were more abundant inside than outside the bays than the salt water species. B/eak and roach species showed high abundancy inside the bays, whilst the salt water herring was natura/ly found more outside the bays.
The studied migratory parameters showed indications of regulatory effects on fish migration between the interior and exterior of the bay. The temperature during the major spawning season, may, were c/ear/y higher inside the bays than outside, which in tum can be stated to be advantegous for the spawning for several species. Also, the turbidity was found to be higher inside the bays than outside. The Oxygen condition inside the bays was poorer than outside the bays. However, the oxygen conditions in the water was high/y varying between the bays .. The leve/ of salinity inside the bays was often /ower than outside the bays, especially during may when the meltwater mixed with the water inside the bays.
The studied migratory parameters showed indications of regulatory effects on fish migration between the interior and exterior of the bay. The temperature during the major spawning season, may, were c/ear/y higher inside the bays than outside, which in tum can be stated to be advantegous for the spawning for several species. Also, the turbidity was found to be higher inside the bays than outside. The Oxygen condition inside the bays was poorer than outside the bays. However, the oxygen conditions in the water was high/y varying between the bays .. The leve/ of salinity inside the bays was often /ower than outside the bays, especially during may when the meltwater mixed with the water inside the bays.