Population Decline
Though the American paddlefish was once common throughout the Midwest, overfishing and habitat changes have caused major population declines; both the meat and roe of Polyodon spathula are desirable as food. Dams and other barriers can prevent the fish from recolonizing places where they once occurred and can deny them access to important critical habitats such as spawning areas. Until about 1900, the species was also found in Lake Erie and in river systems tributary thereto in the U.S. and Canada. Invasive species such as zebra mussels have reduced the number of zooplankton in the Great Lakes to such low levels that any hypothetical reintroduction program would seem likely to fail. Recently, paddlefish were spotted in the Danube river. It has not been determined whether these fished escaped from Romanian or Bulgarian fish farms during the 2006 European floods, or whether they were let into the Danube earlier and matured in the river.
Read more about this topic: American Paddlefish
Famous quotes containing the words population and/or decline:
“In our large cities, the population is godless, materialized,—no bond, no fellow-feeling, no enthusiasm. These are not men, but hungers, thirsts, fevers, and appetites walking. How is it people manage to live on,—so aimless as they are? After their peppercorn aims are gained, it seems as if the lime in their bones alone held them together, and not any worthy purpose.”
—Ralph Waldo Emerson (1803–1882)
“We can recognize the dawn and the decline of love by the uneasiness we feel when alone together.”
—Jean De La Bruyère (1645–1696)