Fish Introductions into North America: Patterns and Ecological Impact

Abstract

The transplantation of fishes has a long history in Western culture, beginning with the Romans, who brought carp (Cyprinus carpio) from the Danube River to Italy (Balon 1975). As Christianity spread throughout Europe, carp entered local fish communities, initially as escapees from monastery ponds. More deliberate colonizations were made in Scandinavia, where the introduction of indigenous salmonids into alpine lakes was apparently a regular practice by the 12th century A.D. (Nilsson 1972). Small-scale introductions continued until the 1840s, when the discovery, in France, of artificial propagation techniques for fish made introductions possible on a much larger scale (Regier and Applegate 1972). The idea of enhancing wild fish populations through the introduction of hatchery-reared fish quickly spread to North America and by the 1870s private, state, and federal fish hatcheries were common. The most important species reared at this time was the carp, which by 1890 was found throughout North America, thanks to the development of railroads and fish transport cars. Other species were raised as well, however, so that by 1873 a railroad car containing 300,000 fish of 10 species was on its way to California (Sheeley 1917). Such cars usually carried Pacific coast salmonids back to the eastern seaboard on the return trip. This practice of taxon redistribution (Regier and Applegate 1972) continues to the present time, not only with fish but with other aquatic organisms as well (e.g., Carlton 1974).