Wildlife at Bothnian Bay - fishes and other animals
Bottomfauna
|
|
One of the biggest differences between the Bothnian Bay and the Bothnian Sea is the lack of mussels in the northern basin due to the low salinity. The number of macroscopic bottom dwelling animal species is far lower in the Bothnian Bay than in the Baltic proper. There are crustaceans such as Monoporeia affinis and Saduria entomon in the Bothnian Bay, but their number is lower than in the Bothnian Sea. Monoporeia affinis stands, though, for a considerable part of the soft bottom zoobenthos in the Bothnian Bay. |
Fishes
Cold water species like Baltic herring (Clupea harengus L.), vendace (Coregonus albula L.), whitefish (Coregonus lavaretus) and four-horned sculpin (Myoxocephalus quadricornis L.) dominate in the Bothnian Bay, whereas warm water species like perch (Perca fluviatilis) and roach (Rutilus rutilus L.) increase in importance towards the south. The number of marine fish species is lower in the Bothnian Bay than in the Bothnian Sea. Many species breed in river mouths since these warm up earlier and provide more food than the archipelago. This means that the conditions of the rivers strongly affect the fish populations in the area.
|
The number of vendace in the Bothnian Bay, for example, has drastically dropped since the 1970's and it is only in recent years that the population has started to recover. Fishing is regarded as the main factor that affects the vendace population in the Bothnian Bay, but also biotic as well as abiotic factors can be involved. |
|
Updated 04.12.2009