Location of Spawning Shore Crabs, Carcinus Maenas (L., 1758) (Decapoda, Brachyura)

Several authors have described the common shore crab Carcinus maenas as a migratory species, leaving the sublittoral zone during the coldest winter months. Adult crabs in general and ovigerous females in particular migrate to deeper and more stable water conditions during the cold season. Ovigerous females may seek deeper water to find stable conditions according to salinity and temperature. However some crabs are found close to the low water level. No large sample of females has been reported during the winter. Female shore crabs, all > 25 mm carapace width, were collected at the island Herdla, north of Bergen on the western coast of Norway and 202 in early October 1986. No females were found below six m. Another 117 females had been caught by creels in Sep of the same year and kept in the bay. None had external eggs.