Recovery of upper Colorado River basin fish (Continued)

Designated 'critical habitat' Under the Endangered Species Act, the U.S. Fish and Wildlife Service has primary responsibility to preserve not only threatened and endangered species, but also the natural resources on which they depend. In fulfilling this responsibility, in March 1994, the Department of the Interior designated 1,980 miles of the Colorado River as "critical habitat" for Colorado pikeminnow, razorback sucker, bonytail and humpback chub.

The areas are primarily federal lands and to a lesser extent tribal, state and private lands in portions of Colorado, Utah, New Mexico, Arizona, Nevada and California. The action was the outcome of a lawsuit by the Sierra Club Legal Defense Fund and a subsequent court order. Under certain circumstances the U.S. Fish and Wildlife Service now has more authority to protect the waters and land that are considered critical to the fishes' recovery. In making the critical habitat designation, the Service considered economic and other relevant impacts as required by section 4 of the Endangered Species Act. After reviewing available information, no areas were excluded from the proposed designation based upon economic or other relevant impacts, although some river reaches were adjusted based on biological information received during the public comment period.

These fish have similar habitat requirements and historically lived in the same rivers. Therefore, the areas designated for each of the four fish overlap. The 1,980 miles of designated critical habitat includes 1,724 miles of river reaches for the razorback sucker, which is 49 percent of its historical range; 1,148 miles for the Colorado pikeminnow, which is 29 percent of its historical range; 379 miles for the humpback chub, which comes to 28 percent of its historical range; and 312 miles for the bonytail, which amounts to only 14 percent of its historical range.

In Colorado and Utah, critical habitat for endangered Colorado River fish covers the following stretches of river:

• Colorado River from Rifle, Colo., to Lake Powell.
• Gunnison River from Delta, Colo., to Grand Junction.
• Yampa River from Craig, Colo., to the Green River.
• White River from Rio Blanco Dam to the Green River.
• Green River from Dinosaur National Monument to Lake Powell.

(There is no critical habitat in Wyoming.)

For critical habitat rules to apply, there must be some type of federal involvement. Private landowners could be affected by critical habitat rules when their planned action requires federal authorization, such as a permit or license, or when they are receiving federal funding, including federal loans or Soil Conservation Service money for constructing a pond. For example, section 404 of the Clean Water Act generally requires landowners to obtain permits from the U.S. Army Corps of Engineers when planning to stabilize a riverbank, excavate an area near waters in the 100-year flood plain or place "fill material" in the water or in a wetland. These types of action include dredging, filling in wetlands, mining for sand and gravel, constructing boat ramps and placing rocks in the river to build riprap, jetties or small dams.

For these species of fish, critical habitat is defined as all areas within the 100-year flood plain that provide the following three characteristics:

• A sufficient quality and quantity of water needed by the fish at each life stage.
• Physical characteristics such as side channels, backwaters, flood plains and bottom lands, which are used by the fish as spawning, nursery, feeding and rearing sites.
• An adequate food supply and other biological characteristics.