Fresh Water Clams?

[gozzer]

I've always thought that the Swan Mussel was a native to British waters and that the swan mussels filter the water and can help keep the water healthy.

Certainly they can be found in a lot of good waters that hold a healthy stock of quality fish.

 

Does anyone out there know if this is true?

 

They are indeed native to Britain BB, but less common in Scotland.

 

They are also among several native species under threat from the introduced zebra mussel, (a native of Russia, I think).

 

A fishing lake in Lancashire has experienced increased water clarity and reduced fish biomass coincidental with the arrival of zebra mussels, while a newly recorded population in Barden Lake, Kent, appears to be having a deleterious impact on native unionid mussels, particularly the swan mussel (Anodonta cygnea) and, more, recently the painter's mussel (Unio pictorum). Repeated surveys in the River Thames, River Great Ouse and Barden Lake showed that the proportion of unionid mussels infested by zebra mussels had increased significantly in all sites studied during the past one to five years.

 

John.