A brief history of aquatic resource use in medieval Europe

Humans have exploited European aquatic resources since at least the Palaeolithic, but during the Middle Ages rising human populations and demand initiated great changes in many fisheries. To help understand the past and present of the Wadden Sea, this paper sets the main developments of medieval fisheries in the context of changing larger European social and aquatic environments ca. 500-1500 A.D. Anthropogenic influences on fish populations and aquatic habitats interacted with natural environmental variations. Both nutritional and cultural needs shaped human consumption of aquatic organisms. Many fisheries met the demand for food by economic reorientation from subsistence to artisanal and then even fully commercial purposes. Exploitation slowly shifted from limited or deteriorating local inland and inshore fish populations to frontier, commonly marine, and increasingly pelagic resources. Some inland regions developed aquaculture to enhance local supplies of fresh fish. General processes are illustrated by case studies of selected indicator species from freshwater and marine habitats generally pertinent to the region surrounding the Wadden Sea. Anadromous salmon (Salmo salar) and sturgeon (Acipenser sturio) were negatively affected by overfishing and by unintentional human alteration of critical habitat. Habitat preferences of catadromous eel (Anguilla anguilla) and exotic carp (Cyprinus carpio) let these species gain from medieval human activities. In the case of herring (Clupea harengus), Europes largest early commercial marine fishery, technological innovations which raised production and consumption played off against long-term consequences of intensely exploiting sensitive natural systems.