Images

A US Geological Survey hydroacoustic survey boat measures velocity profiles on the Upper Missouri River.

Research hydrologist Dr. Susannah Erwin and hydrologic technician Brian Anderson inspect ADCP data on the Upper Missouri River.

Student Contractor Garrett Cook processes a drift sample collected on June 27 shortly after the free embryos and beads were released. Note the small cluster of pallid sturgeon free embryos and green beads in the lower portion of the sorting tray. These embryos and beads were elements of the Upper Missouri River drift experiment.

Pre-deployment briefing for the Upper Missouri River Pallid Sturgeon Drift Study. Fish biologists and physical scientists from Montana Fish Wildlife and Parks, US Geological Survey, U.S. Fish and Wildlife Service, University of Montana, Nebraska Game and Parks Commission, and US Army Corps of Engineers go over the sample design and assignments.

Distribution of free embryos to boats in preparation for mass release.

Simultaneous mass release of 700,000 free embryos from boats distributed across the channel of the Upper Missouri River.

The rhodamine-WT dye was injected in the river uniformly across the channel.

USGS scientists prepare to mix rhodamine-WT dye for the dye trace experiment.  The suits are to keep the harmless dye off of clothing.

USGS scientists conducted a dye-tracer study in June 2016 on the Missouri River about 10 miles downstream of Fort Peck Dam, Montana. The public can expect to see the Yellowstone River turn a similar color in the vicinity of the injection site when scientists conduct a dye study near Glendive, Montana in late June, 2017.

Developing pallid sturgeon embryo.

Macro photo of a developing pallid sturgeon embryo. Developing embryo appears light gray

Biologists at Columbia Environmental Research Center drawdown and seine a pond to collect reproductive pallid sturgeon.  The pond has been specially designed to provide turbid, flowing water that pallid sturgeon need to thrive.

Hoffstadt Creek is one of the salmon release sights after being radio tagged. This picture is taken just downstream from the release sight after a fish release.

These juvenile bighead carps are used to find potential physical, biological or chemical controls as part of an integrated pest management approach for natural resource managers.

Asian carp are invasive species that could pose substantial environmental risks and economic impacts if they become established.

These juvenile silver carps are used to find potential physical, biological or chemical controls as part of an integrated pest management approach for natural resource managers.

Asian carp are invasive species that could pose substantial environmental risks and economic impacts if they become established.

A USGS scientist operates a Petite Ponar substrate sampler to sample bed material in an area identified as a pallid sturgeon spawning location on the Yellowstone River, North Dakota.

A close-up image of lignite-dominated gravel sampled from a spawning area with Petite Ponar sampler.

Collecting and storing substrate samples using a Petite Ponar sampler (top right) for later analysis. 

USGS research vessel outfitted with a compact multibeam sonar echosounder system with an inertial motion unit and real time kinematic positioning global positioning system (RTK GPS) surveys the Yellowstone River near Fairview, North Dakota.

Pallid sturgeon eggs become adhesive minutes after fertilization.  Scientists are working to understand the factors that influence the adhesiveness of sturgeon eggs.

Acoustic telemetry transmitter used to monitor shovelnose sturgeon and pallid sturgeon during spawning in specially constructed ponds at the Columbia Environmental Research Center.