Skip to main content
U.S. flag

An official website of the United States government

Comprehensive Sturgeon Research Project Blog - 2018

The USGS Comprehensive Sturgeon Research Project is a multi-year, interdisciplinary research study to determine factors leading to spawning and survival of the endangered pallid sturgeon and the closely related shovelnose sturgeon. 

Click here to see the previous year's blog or Click here to return to the 2021 blog


Local researchers taking their science to AGU

December 7, 2018


With the 2018 American Geophysical Union fall conference just around the corner, Comprehensive Sturgeon Research Project scientists are proud to announce they have once again been given the opportunity to share their recent research and accomplishments with attendees. Scientists from around the world will convene in Washington, D.C. on December 10th for the four-day conference. Dr. Susannah Erwin will lead the CSRP sessions with oral presentations on the following:

Laboratory experiments to evaluate hydraulic factors mediating dispersal of an endangered sturgeon

By: Susannah O. Erwin, Kimberly A. Chjonacki, Jeffery D.G. Marr, Maura O. Roberts, Jessica L. Kozarek, Aaron J. DeLonay


Interception-rearing complexes: An explicit experiment in large-river restoration to promote survival of larvae of the endangered pallid sturgeon (Presented for Dr. Robert Jacobson)

By: Robert B. Jacobson, David Marmorek, Carl Schwarz, Brian Ma, Susannah Erwin, Nathan Gosch, Todd Gemeinhardt, Joseph Bonneau


Hydrologist Carrie Elliott will also be in attendance with a poster titled “Characterization of a gravel to sand transition on the Lower Yellowstone River, Montana”


For a copy of the presentation material or poster, please contact the associated authors.



Tomorrow’s Scientists Today

By Aaron DeLonay

August 31, 2018


A critical part of a scientist’s job is to share what they learn with stakeholders and the general public.  Sharing knowledge and expertise increases awareness and helps to educate the public about issues that affect the management of the Missouri River and the species that live there.  Scientists from the Comprehensive Sturgeon Research Project participate in numerous outreach and education events throughout the year, but one of the most exciting events is the “Missouri River Days” program sponsored by Missouri River Relief ( in cooperation with Columbia (Missouri) Public Schools.  During the last week in August, more than 250 4th grade students left their classrooms to investigate the Missouri River.  Participating scientists, river experts, and local artists from Missouri River Relief, Universities, and State and Federal Agencies met busloads of enthusiastic students on the banks of the Missouri River at Eagle Bluffs Conservation Area near Columbia, Missouri.  Students got the chance to talk to scientists from the U.S. Geological Survey, U.S. Fish and Wildlife Service, and the Missouri Department of Conservation about the tools they use to study the river and fish that live in it.  They also got the chance to take a ride on the river in boats similar to those used by scientists.  Students also spent time investigating plant communities along the river and using watercolors to translate their scientific experience on the river into art in much the same way explorers Lewis and Clark did more than 200 years ago.  USGS Scientists look forward each spring and fall to the opportunity to reach out and educate the next generation of citizens and scientists.

Biologists from the USGS teach 4th grade students about how scientists capture and study newly hatched pallid sturgeon
Figure 1. Biologists from the USGS teach 4th grade students about how scientists capture and study newly hatched pallid sturgeon in the Missouri River. (Credit: Aaron DeLonay, U.S. Geological Survey. Public domain.)
USGS Fish Biologist, David Combs teaches 4th grade students about the four different species of invasive carps
Figure 2. USGS Fish Biologist, David Combs teaches 4th grade students about the four different species of invasive carps that are present in the Mississippi and Missouri Rivers.  (Credit: Aaron DeLonay, U.S. Geological Survey. Public domain.)
USGS Hydrologist, Carrie Elliott shows 4th grade students the research vessels and survey tools that scientists use to map
Figure 3. USGS Hydrologist, Carrie Elliott shows 4th grade students the research vessels and survey tools that scientists use to map and characterize the habitats used by the endangered pallid sturgeon on the bottom of the muddy Missouri River.(Credit: Aaron DeLonay, U.S. Geological Survey. Public domain.)


Here We Glow

By Kimberly Chojnacki and Aaron DeLonay

August 1, 2018


The fate of pallid sturgeon once they begin to transition from drifting free embryos to benthic larvae is poorly understood.  Scientists believe that during this critical time young sturgeon must move out of the main-stem river and be intercepted and retained in supportive habitats where they begin to feed.  It is critical for scientists to have tools to be able to determine if pallid sturgeon can grow and survive in the habitats where they settle and if improvements in these habitats can aid the young sturgeon.  Scientists can measure growth and survival of sturgeon by marking, releasing, and monitoring them over time.  The small size of sturgeon at this stage makes marking them challenging.  One way to mark very young sturgeon is the use of chemical marks (such as dyes/pigments or fluorescent compounds) by immersion or ingestion.  The chemical binds to or is incorporated into parts of the sturgeon (for example, skeleton, otoliths, mouth parts, fin rays, or scutes) that are hardening through the process of mineralization.  During the spring and summer of 2018, Comprehensive Sturgeon Research Project (CSRP) biologists initiated trials to determine if fluorescent compounds could be used to mark pallid sturgeon free embryos (at 10 days post hatch) and larvae (at 40 days post hatch).  Sturgeon treated with short-term (minutes to hours) immersion in fluorescent compounds were examined in the darkened laboratory using a microscope with a special fluorescence adapter and with a special flashlight and filter that can be used on live specimens in the field.  Early results show that sturgeon can be marked with these compounds and the marks can be detected in the field with minimal effort.  Immersion in a solution of a fluorescent compound, calcein, produced marks visible under blue light in free embryos at 10 days post-hatch (figure 1) and larvae at 40 days post-hatch (figure 2).  Scientists will continue to conduct trials to determine how long the marks will remain detectable in young sturgeon.

Pallid sturgeon immersed in calcein at 10 days after hatching.  Photo taken 20 days after treatment.
Figure 1. Pallid sturgeon immersed in calcein at 10 days after hatching.  Photo taken 20 days after treatment.(Public domain.)
Pallid sturgeon immersed in calcein at 40 days after hatching.  Photo taken 10 days after treatment.
Figure 2. Pallid sturgeon immersed in calcein at 40 days after hatching.  Photo taken 10 days after treatment.(Public domain.)


R/V Lucien M. Brush surveys the Missouri River
R/V Lucien M. Brush surveys the Missouri River(Public domain.)

Theory and practice of habitat assessments in large rivers

By Robert Jacobson, Ph.D.

July 27, 2018


Scientists with the Comprehensive Sturgeon Research Project have agreed to present an 8-hour workshop on habitat assessment methods at the 2018 Annual Meeting of North American Sturgeon and Paddlefish Society. The meeting will be held in Columbia, Missouri, October 21-25, 2018. The objective of this workshop is to acquaint participants with theoretical and practical aspects of evaluating aquatic habitats in large rivers. The presenters are members of the habitat dynamics team in the River Studies Branch, USGS, Columbia, Missouri. The team has two decades of experience collecting and evaluating habitat data on large rivers, with emphasis on the Missouri River and application to the endangered pallid sturgeon.


Visual depiction of the bathymetry of a stretch of the Missouri River
Visual depiction of the bathymetry of a stretch of the Missouri River(Public domain.)



The workshop will cover objectives and sample design, instrumentation basics, instrumentation deployments, and data management, reduction, and analysis. The deployments discussed will include a range of complexity (and cost) from consumer grade depth finders and sidescan to complex hydroacoustic mapping using acoustic Doppler current profilers, multibeam echosounders, and high-resolution sidescan. Analytical methods will include data reduction for GIS visualizations, data feeds to support multidimensional hydrodynamic modeling, and statistical assessments of habitat selection. The all-day workshop will include a short trip to the Missouri River to view hydroacoustic data collection in action.


Contact: Robert Jacobson, Ph.D.





Going with the flow

By Kimberly Chojnacki, Susannah Erwin, Ph.D., and Aaron DeLonay

June 27, 2018


Laboratory studies of the Comprehensive Sturgeon Research Project (CSRP) are designed to examine environmental conditions that control development, behavior, and survival of pallid sturgeon. To date, laboratory experiments have been conducted in facilities capable of simulating a limited range of physical conditions. To bridge the gap between laboratory environments and actual river conditions more effectively, the next generation of experimental work requires facilities that better approximate the real river.

In mid-June 2018, CSRP researchers began a series of trials with recently hatched pallid sturgeon in a flume located at the University of Minnesota, Saint Anthony Falls Laboratory (SAFL) in Minneapolis, Minnesota. Each trial has a different stage of development from newly hatched, drifting free embryos to larvae at the onset of active feeding (What is a free embryo? See previous blog entry “A Change is Gonna Come”). In contrast to the challenges of working in a deep, muddy, and unpredictable river, the flume provides an experimental channel where scientists can control and manipulate conditions like water velocity, water quality, sediment transport, and substrate. The SAFL flume is a continuously flowing oval; 7.5 meters in length and 1.8 meters wide. The flume uses a motor-driven paddlewheel for moving water and is capable of maintaining hydraulic conditions that are appropriately scaled for young sturgeon and other river fishes. The flume is also equipped with an acoustic Doppler velocimeter (ADV) that is moved through the flume on a computer-driven carriage to map velocity and other hydraulic metrics with high-resolution.

In the experimental trials at SAFL, researchers are evaluating movement, behavior, and survival of the free embryos or early larvae as velocities range from 10 to 25 centimeters per second. The performance of each life stage will be analyzed in relation to flume configuration and velocity fields. This collaboration between USGS and SAFL scientists and engineers will produce data to improve understanding of drift rates of larval pallid sturgeon and to design a new flume to be built at the USGS – Columbia Environmental Research Center.

Researchers examine ADV data
Susannah Erwin, Ph.D. (USGS) and Jeff Marr (University of Minnesota) examine high resolution velocity data collected using an acoustic Doppler velocimeter (ADV) at the University of Minnesota, Saint Anthony Falls Laboratory (SAFL).(Public domain.)


Deploying to Montana

By Kimberly Chojnacki

June 6, 2018


Scientists from the River Studies Branch, CERC, began their annual migration to eastern Montana this week to continue critical research on factors that limit populations of the endangered pallid sturgeon. The first wave of six scientists, two trucks, two jet boats, and mountains of instrumentation left Columbia, Missouri on Sunday morning, June 3, and started deployment on the Upper Missouri River near Wolf Point, Montana on June 5. The first wave is concentrating on hydroacoustic surveys to compile multidimensional hydraulic and particle drift models that will be applied to estimates of downstream dispersal of pallid sturgeon larvae. The second wave of 3 scientists will arrive in Sidney, Montana on June 8 to help with tracking and recaptures of reproductive pallid sturgeon in the Yellowstone and Upper Missouri Rivers. After June 15, two additional waves of 6-9 scientists and boats will arrive to carry out a comprehensive evaluation of pallid sturgeon spawning, spawning habitats, sediment transport, and larval drift in the Yellowstone River. The effort will continue through the pallid sturgeon spawning season, at least until the first week of July.

The annual effort is part of the USGS-U.S. Army Corps of Engineers collaboration under the Missouri River Recovery Program. The research is part of the CERC Comprehensive Sturgeon Research Project (Aaron DeLonay, project chief), in partnership with Montana Fish Wildlife and Parks and Southern Illinois University. This year the CERC team will be joined by a crew from the North Dakota Water Science Center who will be providing sampling of near-bed suspended sediment.

USGS Survey Boat on the Missouri River
One of two USGS-CERC hydroacoustic survey boats collecting hydroacoustic data downstream from Wolf Point, Montana.(Public domain.)


Scouting for Science

By Kimberly Chojnacki

April 18, 2018


This month, the USGS Columbia Environmental Research Center (CERC) hosted a tour for a troop of Girl Scouts.  Approximately 12 girls in 4th through 6th grades gathered at CERC to learn about various research at the center and types of jobs available in science.  Female scientists from the branches of biochemistry, ecology, river studies, and toxicology spoke to the group on an array of topics including environmental DNA, invasive species, habitat mapping, fish behavior, and microscopy.  Additionally, scientists were available to discuss educational opportunities and other science topics of interest to the scouts in a ‘cookies and questions’ session following the tour.

Geologist, Carrie Elliott, explains how scientists map the riverine habitats of the endangered pallid sturgeon
Geologist, Carrie Elliott, explains how scientists map the riverine habitats of the endangered pallid sturgeon using a multibeam echosounder.(Public domain.)



Project Update: Temperature, Time, and Thousands of Specimens

By Kimberly Chojnacki and Aaron DeLonay

March 8, 2018


Water temperature is the most important environmental factor influencing the development of sturgeon early life stages.  Unhatched embryos developing in the substrate and hatched free embryos dispersing downstream in the current of the Missouri River and its tributaries may experience a wide range of temperature variation.  During 2016, CSRP biologists began a study to document the effects of temperature on the development of pallid sturgeon free embryos (from the time of hatch to the initiation of active feeding).  Eggs from four adult female pallid sturgeon of Upper Missouri River origin were fertilized with milt from six males in the laboratory.  The resulting fertilized eggs and free embryos were reared separately under controlled conditions in the laboratory at temperatures ranging from 14 to 26 degrees Celsius.

Beginning on the day of hatch, biologists collected and preserved free embryos from each female and temperature treatment at four hour intervals around the clock until the developing sturgeon expelled their yolk plug and transitioned into exogenously feeding larvae.  These preserved specimens were then measured, microscopically examined and their development characterized using a suite of morphological traits.  During January 2018, after hundreds of hours of laboratory work, biologists finished the thorough microscopic examination of the approximately 7,150 specimens that were collected during 2016.  Soon, the data analysis and report writing will begin. This work will provide a high-resolution understanding of the effect of temperature on developing free embryos.  Understanding how the rate of sturgeon development and time needed to reach important developmental milestones changes with temperature will allow biologists to correlate stages of development with critical behavioral endpoints (orientation to light or the current, swimming capacity, or settling to the bottom).  Understanding this “developmental map”, and knowing where spawning occurs and the temperature regime experienced by dispersing free embryos within a segment of river, scientists will be better able to refine critical dispersal models to guide management actions.

USGS lab technician examines a sturgeon specimen
Biological science technician, Killian Kelly, examines specimens collected to examine the effects of temperature on development of pallid sturgeon free embryos at the Columbia Environmental Research Center.(Public domain.)


Improving lab capabilities at CERC

March 6, 2018


When it comes to science within the Comprehensive Sturgeon Research Project, it often seems that each study provides information that opens more avenues of scientific inquiry. While this is simply the nature of scientific research, the expanding range of studies often leaves scientists short on time and resources to pursue all of the unknowns. While we can’t add extra hours in a day, we can do something about the resources offered to scientists so their time and efforts are as productive as possible.

The 2017-2018 renovations currently underway at the Columbia Environmental Research Center (CERC) aim to do just that.

Expected to be fully functional in late spring or early summer 2018, the CERC is repurposing 3,400 square feet of existing infrastructure into a biosecure wetlab to support endangered species and invasive species studies. By providing state of the art water treatment and environmental control within a large new dedicated space, scientists will greatly increase the capacity for culture of adults and early life stages.  The facility will also provide for the ability to conduct multiple, concurrent studies—a huge asset when dealing with fish like the pallid sturgeon where early life stages are available only for a short time each year.

In an effort to create an efficient, comprehensive space, the building will be generally divide into four sections: behavioral research space, culture and rearing space, a flexible, adaptive research space, and facilities to treat incoming and effluent water. This means everything involved in a study from the water to the fish to the environment can be controlled from start to finish within the single building isolated from the outside environment. Studies with Asian carps are expected commence in the new building in summer of 2018, while sturgeon studies will begin in later 2018–early 2019.

Planned layout for upcoming construction
Planned layout for upcoming construction in the Columbia Environmental Research Center's new wetlab. (Public domain.)


Sharing Science at the Missouri River Natural Resource Committee's Missouri River Conference

March 8, 2018


When working on complex problems with ecosystems as expansive and diverse as the Missouri River, it quickly becomes evident that information sharing and collaboration are necessary for scientific advancement. A number of events each year bring together scientists, managers, and concerned citizens to discuss the science, and further the understanding of challenges facing Missouri River management. One such event, the Missouri River Natural Resource Committee’s Missouri River Conference from March 20-22nd in Nebraska City, Nebraska, serves as an opportunity for scientists from the Columbia Environmental Research Center to present results from ongoing studies and discuss future research initiatives under the Comprehensive Sturgeon Research Project (CSRP) to more than 100 conference attendees from across the Missouri River basin.


Presentations by CSRP scientists included six oral presentations and a poster on the following topics:


Oral Presentations:

Pallid Sturgeon Use, Migration, and Spawning in the Yellowstone and Missouri Rivers During 2017 by Dr. Pat Braaten

Downstream Dispersal and Retention of Pallid Sturgeon and Shovelnose Sturgeon in an Experimental Mesocosm by Aaron DeLonay

Lower Missouri River Bend-scale Classification: Application to Understanding and Management of Pallid Sturgeon Habitats by Dr. Robert Jacobson

Comparative Development of Pallid Sturgeon and Shovelnose Sturgeon Free Embryos Reared in the Laboratory by Kim Chojnacki

Update on What We Know About Pallid Sturgeon Spawning Habitat: Implications for Restoration, Design, and Monitoring on the Lower Missouri River by Carrie Elliott

Improving Hydraulic Models and Exploring Uncertainty Using Dye-Trace Experiments in the Upper Missouri and Yellowstone Rivers by Dr. Susannah Erwin

For more information or to read the presentation abstracts, please see the MRNRC presentation abstracts page at



Research Framework to Support Missouri River Adaptive Management: Comprehensive Sturgeon Research Project 2018–2020 by Aaron DeLonay

For more information or to read the poster abstract, please see the MRNRC poster abstracts page at




To revisit what happened in 2017 at the Comprehensive Sturgeon Research Project, click here!

To return to the Comprehensive Sturgeon Research Project Overview, click here!

To return to River Studies, click here!