"Razorbacks spawn upstream. As the larval fish emerge from their eggs, they're swept downstream. If they manage to be swept into a natural backwater, like those now re-exposed by one of our breached levees, their chance of survival goes way up."

Another project, a larval drift project, used colorful beads to track drifting patterns. "We looked at how something small, like a fish larva, would drift in the river," Hedrick said. "This study has helped us learn how drift behaves in the river at different water levels. This information will help us fine tune releases from Flaming Gorge dam to increase the number of fish that survive."

Hedrick said the program has also stocked 1- and 2-year-old razorback suckers into the Stirrup flood plain. Fish were stocked there to learn which age classes tend to move back into the river after being in the flood plain for most of their young life.

"We know the larval fish drift into the calmer flood plain habitats shortly after they swim up from their eggs," she said. "Early in the year, these calm-water flood plain habitats are much more productive than the river, and the larval fish grow much more quickly in them. One study even showed that the young razorbacks that don't make it to the flood plain but stay in the river will probably starve to death due to a lack of food in the early spring.

"However, we really don't know how long these fish need to stay in the flood plain before they move back out into the river," Hedrick said." We're really trying to understand the whole life history of the razorback sucker. Hopefully this new study will help us draw some conclusions about their movement out of the flood plain."