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and perhaps other endangered fishes were inventoried, classified, and prioritized using 5 criteria during 1993 (Irving and Burdick 1995). Bottomland Habitat Sites in the Green River Subbasin. The top ranked bottomland habitat sites in the Green River (32) were located between Pariette Draw and Escalante Ranch (Irving and Burdick 1995; RM 238-310 [RK 383-499]; 6,093 acres [2,466 ha]). Six sites on the Ouray National Wildlife Refuge (RM 249-265 [RK 401-427]; 2,265 acres [917 ha]) were ranked either as 1 or 2. Floodplain terraces comprised the vast majority (n = 99 or 75%) of bottomland habitat types in the Green River Subbasin while floodplain depressions comprised the remaining 25% of bottomland sites. Four percent of the 132 potential bottomland sites along the Green River were separated from the river by natural levees while 11% were separated by levees constructed by humans. Approximately 20 miles of the Green River consisted of natural and human-constructed levees at 20 sites. Bottomland Habitat Sites in the Colorado River Subbasin. The top ranked bottomland habitat sites along the Colorado and Gunnison rivers were scattered in four general areas (I rvi ng and Burd i ck 1995): (l) Colorado River between Debeque and Rifle, Colorado (RM 203-240 [RK 327-386]); Grand Valley reach of the Colorado River between Loma and Palisade, Colorado (RM 152-185 [RK 245-298]); Colorado River between McGraw/Hotel Bottoms and the Cisco boat landing (RM 99-110 [RK 159-177]); and the Gunnison River near Delta, Colorado (RM 50.2-54.2 [RK 81- 87]). Bottomland habitat sites in the Colorado River Subbasin consisted of 37% floodplain terraces, 21% gravel-pit ponds, and 20% side channels. Natural levees separated 14.6 miles (23.6 kilometers) of the 158 bottomland habitat sites along the Colorado and Gunn i son ri vers wh il e 34.9 mil es (56.3 kilometers) were separated by levees constructed by humans. Federal agencies own most (75%) of the bottomlands in the vicinity of Brown's Park and a high percentage (58%) of the bottomlands between Escalante Ranch and Brennan Bottom on the Green River (Irving and Burdick 1995). All of the bottomlands on the Ouray National Wildlife Refuge and the majority of bottomlands between Desert Spring and the confluence of the Green and Colorado rivers are in federal ownership. A smaller percentage of the bottomland habitat along the Colorado (15%) and Gunnison (22%) rivers were in public (i.e., federal and state) ownership. The largest proportion of bottomland habitat along the Colorado River in federal ownership (83%) was within Canyonlands National Park. Obviously, sufficient bottomland habitat is in public ownership along the Colorado and Green rivers so that experimental removal of levees can be evaluated as to zooplankton and benthic invertebrate production and responses by endangered as well as nonnative fishes. Levee removal should be confined to low floodplain terraces in public ownership where thorough evaluations can be made of these efforts. Experiments on public property would preclude high streamflow releases from upstream dams that would cause sociological problems associating with the flooding of private agricultural lands and the production of mosquitoes that could pose human health problems. Leasing of bottomlands in private ownership can be explored if field experiments of floodplain enhancement or restoration are successful on public properties. 17