European Invasion

The Chinese mitten crab was first identified as a nonindigenous species in Germany in 1912. In the 1930's the mitten crab population exploded, literally over-running stream banks; swarming through city streets; and causing extensive physical damage to dams, levees and river banks (Slack 1996). Migrating up many of Germany's major rivers, hordes of crabs devastated fisheries and spread throughout most of Western Europe, eventually reaching the Atlantic Ocean having crossed a system of freshwater canals into France (Cohen and Carlton 1997). The staggering populations seen in the 1930's have never returned and the reason for this population explosion remains unknown.


created 5/4/98