Body weight, condition, and carapace width and length in the Chinese mitten crab (Eriocheir sinensis H. Milne-Edwards, 1853) collected from the Szczecin Lagoon (NW Poland) in spring and autumn 2001

A newcomer to the Baltic Sea, the Chinese mitten crab is especially abundant in the Szczecin Lagoon (NW Poland), where it was first reported in 1927. Body weight, and carapace width and length, were studied in 647 individuals collected with fyke nets in the Szczecin Lagoon from 30 March – 18 April2001 and from 5–21 November 2001. 51.01% of the 543 autumn specimens were males, but only 30.97% of the 113 spring specimens were males. Body weight varied from 45.1 to 306.5 g, carapace length from 41.07 to 81.02 mm and carapace width from 46.68 to 88.85 mm. The autumn crabs were significantly heavier than the spring specimens.