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family lots until they can be PIT-tagged and are stocked into the river. In hatchery ponds, the larvae and juveniles feed strictly on zooplankton whereas, in grow-out ponds, they become acquainted with macroinvertebrates so that they may become better foragers following stocking. These grow-out ponds should not be connected to the river by a surface channel or underground outlet pipe, should be predator- free, and secure from flooding to prevent premature escape of endangered fish into river. If a hydrological connection between the pond and river is required, the outlet should be screened. Virginia Acres Pond, immediately north of Pickup Pond, is one such pond that is currently being examined by the Recovery Program to determine its suitability as a grow-out pond for juvenile razorback sucker. RECOMMENDATIONS Major recommendations (underscored print) from this study are: L Avoid Connecting Isolated Ponds to the River That are Deep Depressions. Floodplain habitat should not contain irregular -shaped, deep depression ponds. These type of habitats are perennial havens for nonnative fishes and provide potential sources for nonnative fishes to escape to the mainstem river. If deep depression habitats cannot be rehabilitated by recontouring and reshaping to provide seasonal, ephemeral habitat, they should be sufficiently diked to prevent escapement of nonnative fishes such as centrarchids and ictalurids. 2. Back - Fill Gravel - Pit Ponds and Reconnect them to the Mainstem River to Flood and Drain Seasonally to Benefit Native Fishes and to Control Nonnative Fishes. As a part of restoration, where feasible and practical, gravel-pit ponds that are relatively shallow could be reclaimed by back-filling, sloped to drain as the river subsides, and allowed to function as an ephemeral wetland. Reconnecting former floodplain habitat to the river to provide off-channel habitats will benefit native fishes. This action would include eradicating nonnative fishes from depression habitats such as former gravel-pit ponds prior to their being back-filled and the pond bottom recontoured so that they steeply slope toward the river to allow seasonal flooding and draining, even during high-water years. The bottom of shallow gravel-pits could be back-filled and recontoured to create stepped terraces leading to the river so that they slope toward the river. These features would then be reconnected to the river to allow fish access during high-flow periods. Modifying these man-made gravel-pit ponds to function as historical terraces may be more cost-effective and practical for managing and controlling nonnative fishes than long- term control measures such as screening ponds, chemical treatment, or mechanical pumping and removal. 27