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sunfish (0.4). For Hotspot Pond, largemouth bass (2.0), western mosquitofish (2.1), black crappie (1.2), green sunfish (0.4), and black bullhead (0.1). The following conclusions from this research were: 1) the species composition of both ponds was predominantly nonnative during all three sampling periods, 2) native fishes used the two connected ponds mostly during runoff, 3) five species of sub-adult and adult nonnative fishes moved between the two ponds that were connected to the river; white sucker and largemouth bass migrated the most between the two ponds, 4) within four months following draining of Gardner Pond, removal of nonnative fishes, and construction of a connection channel, nonnative fishes invaded and recolonized the pond, and within eight months, five species of nonnative fishes had successfully reproduced in Gardner Pond. Ponds in the 10-,50-, and 100-year floodplain that have bottoms shaped and contoured as depressions are havens that 'provide perennial, off-channel habitats for nonnative fishes to grow and reproduce. Ponds that are depressions and that are connected to the river allow sub-adult and adult fish uninhibited access to the river ,and to other off-channel habitats connected to the river. Ponds with depressions provide a constant supply source of nonnative fish that can potentially escape to the mainstem river. While depressions benefit native fishes for a period only during runoff, nonnative fishes appear to benefit more from such perennial, lentic habitats. Recommendations were to: 1) avoid connecting isolated ponds to the river that are irregular-shaped depressions because such habitats provide perennial havens for nonnative fishes; 2) reconnect former floodplain habitat to the river to provide off-channel habitats that will benefit native fishes and at the same time reduce proliferation of nonnative fishes. Whenever floodplain habitats are connected to the river, hydrological acces~ for fish should be by surface connection and underground culverts and pipes should be avoided because some fish might be shy and will not use such structures; 3) coordinate with gravel mining companies to implement new reclamation procedures to restore-gravel pits as sloped terraces. Gravel-pit ponds that are relatively shallow could be back. filled, sloped to drain as the river subsides, reconnected to the river, and allowed to function as an 'ephemeral wetland. Such modifications may be more cost-effective and practical for managing and controlling nonnative fishes than long-term control measures such as screening, chemical treatment, or mechanical pumping and removal of nonnative fish species; 4) notch or remove portions of levees and dikes that protected former gravel-mining operations at strategic locations to permit the river to reclaim the former floodplain and recreate new in-channel habitats such as flow-through side channels. Restoration projects should include modifying man-made gravel pits to as sloped, terrace habitats. This would include eradicating nonnative fishes from the depression habitats pri or to thei r bei ng back - fi 11 ed, s 1 opi ng them toward the ri ver to allow seasonal flooding and draining, and reconnecting them with the river. Such modifications would provide access and habitat for various life stages of native and endangered fishes. Some level of protection from flooding (i. e., set-back dikes) to agricultural land, and residential and recreational structures should be provided; 5) pursue acquisition of Hotspot Pond from Mr. Van Wagner and develop a Memorandum of Understanding with the Colorado Department of Natural Resources, Division of Parks and Outdoor Recreation, to recontour Pickup Pond. These two former gravel-pits presently connected to the mainstem Colorado River are important off-channel habitats that are used during spring runoff by adult x