Field studies emphasize quantitative estimates of population size and determination of basic life history and habitat requirements. Populations estimates of Colorado pikeminnow and humpback chub are being conducted to determine if these two species are progressing to where downlisting can occur. Because these species declined prior to any knowledge of their life history, basic questions on early life history are being answered, particularly with razorback sucker and bonytail and the role of floodplains as nursery areas for these species.
Update from the Green River:
Pikeminnow have been collected from the Green River in Utah. The Utah Division of Wildlife Resources report seeing several mid-size fish (400 mm) of which many are not tagged. Also collected are smaller pikeminnows from 2009 (150 mm) which indicate signs that populations are increasing.