8231

• UCREFRP Catalog Number: 8231
• Author: Maddux, H. R.
• Title: Draft Environmental Assessment For Procedures For Stocking Of Nonnative Fish Species In The Upper Colorado River Basin.
• USFW Year: 1996.
• USFW - Doc Type: Grand Junction, CO.
• Copyright Material: NO

11. Fathead minnow: Their native distribution is in Central North
America, from the east slope of the Rocky mountains east to the
Appalachian mountains. Commonly introduced as a food source for sport
fish and spread though use as a baitfish in the Colorado River Basin.
Found in a variety of habitats including rivers. lakes. reservoirs. and
ponds. Has been shown to eat larvae of other species. and is also
considered a competitor with young endangered fishes. Fathead minnow
were tied for 5th on the list of 28 nonnative fish species considered to
adversely impact the native fishes in the Colorado River Basin (Hawkins
and Nesler 1991).
12. Common carp: Their native distribution is the temperate regions of
Europe and Asia. Introduced into the Colorado River drainage in the
late 1800's as a food fish. Found in a variety of habitats including
rivers, lakes, reservoirs, and ponds. Eat larvae of other fishes
including Colorado squawfish and razorback sucker. Also competes with
other fishes for food and other resources. Common carp were ranked 4th
on the list--of 28 nonnative fish species considered to adversely impact
the native fishes in the Colorado River Basin (Hawkins and Nesler 1991).
13. Smallmouth bass: Their native distribution is in the United States
from the Great Lakes south to the Tennessee River system in Alabama and
west to eastern Oklahoma. This fish has been introduced into the Upper
Colorado River as a sport fish. Escapement from reservoirs in the Yampa
and Green rivers and establishment of a reproducing population in the
Duchesne River has greatly increased the abundance of this species. Its
diet includes other fish. Smallmouth bass were ranked 10th on the list
of 28 nonnative fish species considered to adversely impact the native
fishes in the Colorado River Basin (Hawkins and Nesler 1991).
14. Northern pike: Their native distribution in the United States is
primarily from Nebraska east to the Appalachian Mountains, but also
includes parts of Alaska. This fish was first introduced in the Upper
Colorado River Basin (Elkhead Reservoir, Colorado) in 1977 as a sport
fish. Their habitat ranges from lakes to rivers. Their diet is
primarily other fish. Impacts include predation on and competition with
native fishes. Northern pike were ranked 3rd on the list of 28
nonnative fish species considered to adversely impact the native fishes
in the Colorado River Basin (Hawkins and Nesler 1991).
15. Tiger muskie: Tiger muskie are a hybrid cross between northern pike
and muskellunge. Known as a top predator and introduced as a sport
fish. Diet consists primarily of other fishes. Recently introduced in
the Upper Colorado River Basin in Harvey Gap Reservoir in Colorado (as a
sport fish) and Forsyth and Mill Meadow reservoirs in Utah (as part of a
whirling disease control study: to be removed in 1996). This species
does not reproduce and therefore must be maintained by stocking.
Because this species is a recent introduction to the Basin, it was not
included in Hawkins and Nesler (1991).
16. Green sunfish: The native distribution of this species is in North
America east of the Continental Divide and west of the Appalachian
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