OutdoorNebraska

44 2023 Annual Report • Conservation Research studies native fish movement, northern pearl dace survival Barriers to fish movement and changes to habitat availability due to stream channelization may be affecting native fish populations' abundance and distribution in Nebraska. New research by Nebraska Game and Parks explored fish movement through barriers on channelized headwater streams, with a specific focus on northern pearl dace survival, a species of conservation need and one whose population status is limited in Nebraska. Native fish movement was studied over a two-year period on three stream sections with varying severities of culvert drops. Fish were marked both upstream and downstream of the culvert to monitor movement. Year one was considered baseline data, determining where and which native fish species were present in the stream and where they moved over time. In year two, a fish ladder was installed in each of the culverts from May through October, and fish were monitored again. Early analysis shows fish movement where there were ladders. During the study, northern pearl dace survival also was compared in channelized and non-channelized stretches of four headwater streams in the Sandhills. The fish were marked with unique identification tags so researchers could estimate their survival. Results showed northern pearl dace survival was greatly affected by habitat change through channelization practices. Future research may explore stream restoration and the monitoring of channelized headwater streams with a focus on boosting native fish communities, including the northern pearl dace, over time. Missouri River program monitors endangered pallid sturgeon As part of the federal Missouri River Recovery Program, Nebraska Game and Parks monitors the movement and spawning activity of the federally endangered pallid sturgeon in the lower Missouri River. Reproductively ready pallid sturgeon, mostly females, are captured between Gavins Point Dam and the confluence with the Mississippi River and surgically implanted with acoustic telemetry tags. These fish are tracked daily, their spawning behavior documented, and then recaptured to determine their spawning success. In 2023, the agency and partners tracked 11 reproductive female pallid sturgeon. The fish migrated upstream more than 200 river miles and moved up to 18 miles per day. Nine fish successfully spawned in the Missouri River in the study area, with a spawning aggregation located near Ponca State Park. One fish spawned in the Platte River, and one fish didn't spawn. The research will continue in 2024. Partners on the research include the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, the U.S. Geological Survey, the University of Nebraska- Lincoln and the Missouri Department of Conservation. Commission biologist Randy Stutheit helps with pallid sturgeon sampling.

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