Fish

In Kvarken, there are many shallow bays and coves, which are important habitats for several species of fish. In total there are about 40-50 species of fish in the area. Flades and gloes act as "nurseries" for perch, roach and northern pike. The houting thrive a bit further out from the coast in colder water; the same applies to the sea trout. Baltic herring is the most common marine species, and smelt is one of the most important food sources for other fish species. More southern species as the common rudd (Scardinius erythrophtalanus) and the European chub (Squalis cephallus) are rare or absent in Kvarken. Others have their most northern distribution areas here, such as the broad-nosed pipefish and the greater sand eel.

Image 1: Perch (Perca Fluviatilis) in a flad

Image 2: Northern pike (Esox lucius)

But the greatest rarity in Kvarken is probably the critically endangered sea-spawning grayling. The grayling generally thrive in clear, oxygen-rich rivers, streams and lakes, but the grayling found in Kvarken spawn in the brackish seawater. As far as we know, sea-pawning grayling are found nowhere else in the world. It is an endemic species of the area. Today there are very few grayling left in Kvarken. A possible reason is the deteriorating water quality in the area.

The fourhorn sculpin live in deeper and colder water and is one of the relic species of Kvarken. Relic species originate from other seas but have been isolated in the Baltic Sea after the ice age due to the land uplift. The fourhorn sculpin is a bottom-dwelling fish that can live in both freshwater and saltwater. It eats mainly Saduria entomon, another relic species of Kvarken.

Image 3: Fourhorn sculpin (Myoxocephalus quadricornis)

Sources

Hietikko-Hautala T. 2010. Jääkauden jälkinäytös – Merenkurkun saariston maailmanperintö. Waasa Graphics, Vasa

Ollqvist S. 2005. Skötsel- och användningsplan för Mickelsörarna-Rödgrynnorna. Västra Finlands miljöcentrals duplikat 121/2005. Forststyrelsen, Vasa

Rassi P., Hyväringen E., Juslén A., Mannerkoski l. 2010. Suomen lajien uhanalaisuus – Punainen kirja 2010. Miljöministeriet och Finlands miljöcentral, Helsingfors

Rinkineva L., Bader P. 1998. Kvarkens natur. Kvarkenrådets publikationer 10, Vasa

Ruotsalainen E. 2011. Utredning gällande behovet av skötselplan för havslekande harr i Kvarken. Fiskgruppen, Österbottens närings-, trafik- och miljöcentral.

Skau T., Berglund J., Hudd R. 2007. Harrleken. (www-dokument). www.harrleken.nu (besöksdatum 19.10.2012)