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stage of the species. Predation and competition, although considered normal components of this environment, may be out of balance due to nonnative fish species in many areas. Habitat requirements of the fish species included in this designation vary, and what comprises a constituent element for one species may vary from what comprises the same constituent element for the other species. Where an area is proposed for designation for more than one species, the Service has assessed the area against all constituent elements that apply. Additional specific information on primary constituent elements for each of the fish species is given in the next section. Primary Constituent Elements: Species specific definitions Woundfm Adult and juvenile woundfin select runs and quiet waters adjacent to riffles that have sand and sand/gravel substrates. Adults are generally found in habitats with water depths between 0.15 and 0.43 meters (m) [0.5 and 1.4 feet (ft)] with velocities between 0.24 and 0.49 meters per second (m/s) [0.8 and 1.6 feet per second (ft/s)]. Juveniles select areas with slower and deeper water, while fry aze more likely found in backwaters, stream margins or other slow velocity areas, often associated with growths of filamentous algae. Water quality is characterized by seasonally variable temperature, turbidity, and conductivity. Spawning takes place during the period of declining spring flows. Virgin River Chub Adult and juvenile Virgin River chub select deep runs or pools with slow to moderate velocities containing boulders or other instream cover over a sand substrate. Generally, larger fish occupy deeper habitats; however, there is no apparent correlation with velocity. Chub aze generally found in velocities up to 0.76 m/s {2.5 ft/s). Virgin Spinedace Virgin spinedace aze found most often in runs or pools in .clear streams. The presence of cover, in the form of vegetation, boulders, debris, or undercut banks is also characteristic. Substrates in occupied habitats include rubble/cobble, gravel, sand, and silt. Spinedace are most often found in depths of 0.1 to 0.9 m (0.3 to 2.7 ft) and velocities of between 0.1 and 1.0 m/s (0.3 to 3.0 ft/s). Areas Proposed for Designation The critical habitat areas proposed aze those that the Service believes are required for the survival and recovery of each species. Figures 2, 3, and 4 display the proposed critical habitat for the three species. 7