Biodiversity of Freshwaters - Freshwater Ecology: Concepts and Environmental Applications - page 197

Invaders of the North American Great Lakes a TABLE 10.1

Year

Organism detected Source How introduced Effects

Sea lamprey, 1830 Atlantic Shipping canals Decreases native lake trout

Petromyzon marinus
Purple loosestrife, 1869 Europe Released with solid see Sidebar 8.4

Lythrum salicaria ship ballast

Alewife, Alosa 1873 Atlantic Shipping canals Suppresses native fish species;

pseudoharengus new prey for salmon

Chinook salmon, 1873 Pacific Intentional New piscivore; important

Oncorhynchus sport fish

tshawytscha
Common carp, 1879 Europe Intentional Destroys habitat for

Cyprinus carpio waterfowl and fish

Brown trout, Salmo trutta 1883 Europe Intentional New piscivore; important

sport fish

Coho salmon, 1933 Pacific Intentional New piscivore, important

Oncorhynchus kisutch sport fish

White perch, 1950 Atlantic Shipping canals Competes with native fish

Morone Americana
Eurasian watermilfoil, 1952 Eurasia Spread from intentional Competes with native plants

Myriophyllum spicatum introduction in

Washington, DC

European ruffe, 1986 Europe Ballast water Competes with native fish

Gymnocephalus cernuus and eats eggs

Zebra mussel, 1988 Europe Ballast water Biofouling; competes with

Dreisena polymorpha native species

Round goby, 1990 Eurasia Ballast water Competes with native benthic

Neogobius fish; more direct transfer of

melanostomus pollutants to sports fish;

eats zebra mussels

a From Mills et al. (1994) and other sources.

during the past 12,000 years (Johnson et al., 1996), one of the highest known
rates of species evolution ever documented. Many of these species have dis-
appeared during the past two decades from overfishing, introduction of non-
native predators, and eutrophication (Barel et al., 1985; Kaufman, 1992; See-
hausen et al., 1997). About 200 of these species disappeared in a single
decade, primarily because of introduction of the predatory Nile perch (Gold-
schmidt et al., 1993). The Victoria fishes may represent one of the most rapid
speciation events, but species accrued 500 times more slowly than humans
destroyed them.
Researchers generally assume that endemic species are most likely to
go extinct and deserve the most attention for conservation. However, some
cosmopolitan species also could go extinct because they generally rely on
habitats that are temporarily available for colonization and act as fugitives
that move across the landscape from one habitat to another. The massive
alteration of habitats associated with human activities may cause extinc-
tion of such species, and this may have a broader geographic effect on com-
munity formation and ecosystem function than extinction of localized en-
demics (Cairns, 1993).