In the coastal waters of several European countries there is a notable loss of crayfish populations (A Pallipes, A.
Astacus, A. Torrentium) due to pollution, habitat loss, overfishing and the introduction of alien species (mainly N.
American). Services lost include food (domestic varieties fetch twice the price of non-native varieties), regulating
services (trophic effects on prey and predators), recreation and cultural services. Although estimates of the loss
have not been made, estimates of the costs of restoration have. They indicate modest costs (around €225,000 per
stream over 5 years in France) that would be well below the value of the recovered crayfish populations