Poland; Orconectes limosus; Decapoda; crayfish; distribution

Orconectes limosus introduction to European waters started in Germany in 1880. Its range extended then to Poland and France. Now the species occurs widely in Europe, including also Lithuania, Austria, the Netherlands, Switzerland, and newly also in Czech Republic. A recent survey on Polish rivers in 1996-1998 allowed to evaluate the recent distribution of O. limosus in Poland. In a result, crayfish were found in 17 from 38 localities. Only Orconectes limosus was recorded. Its occurrence are more frequent at northern part of Poland - in the down parts of the drainage areas of the Odra and Wistula rivers, and in rivers with smaller watersheds mouthing directly to the Baltic Sea. The wide crayfish range extension has been possible by high density of drainage channels and water ways for ships joining rivers and lakes throughout the whole northern half of Poland.

Orconectes limosus introduction to European waters started in Germany in 1880. Its range extended then to Poland and France. Now the species occurs widely in Europe, including also Lithuania, Austria, the Netherlands, Switzerland, and newly also in Czech Republic. A recent survey on Polish rivers in 1996-1998 allowed to evaluate the recent distribution of O. limosus in Poland. In a result, crayfish were found in 17 from 38 localities. Only Orconectes limosus was recorded. Its occurrence are more frequent at northern part of Poland - in the down parts of the drainage areas of the Odra and Wistula rivers, and in rivers with smaller watersheds mouthing directly to the Baltic Sea. The wide crayfish range extension has been possible by high density of drainage channels and water ways for ships joining rivers and lakes throughout the whole northern half of Poland.