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Comprehensive Sturgeon Research Project Blog - 2023

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. 


Areas of Enhanced Catch Part II

By: Tyrell Helmuth and Caroline Elliott

September 8, 2023

Interception of larval pallid sturgeon drifting downstream in the Missouri River into shallower, slower velocity, off-channel habitats is hypothesized to be critical for growth and survival of early life stages. In the summer of 2022, the U.S. Geological Survey (USGS) collaborated with biologists from the United States Army Corps of Engineers (USACE) to begin focused surveys to determine why larval sturgeon can be reliably captured some areas of the Missouri River (see previous blog, Areas of Enhanced Catchment). These sites are known as Areas of Enhanced Catch (AEC).  In the Lower Missouri River, these areas are often found just downstream of wing dikes.  As part of these surveys, the USGS, is measuring physical and hydraulic characteristics of the areas just upstream and downstream wing dikes associated with AECs.

image of the the Missouri State Capitol
A view of the Missouri State Capitol building on the right bank of the Missouri River from the bow of the U.S. Geological Survey Research Vessel, Lucien M. Brush.  A multibeam sonar unit, with its sound velocity probe can be seen in the foreground mounted on an aluminum mast that is lowered into the river during surveys.

A hierarchical statistical sampling model was developed in 2022.  We used the results from larval catch efforts during 2022 to refine the model to predict catch of larval fish for this year’s efforts (2023). The refined model uses data describing river channel characteristics and wing dike geometry to predict catch of larval sturgeon.  Wing dikes on the Lower Missouri River between the Kansas and Osage Rivers (788 total dikes) were randomly sampled to create a set of wing dikes within a five-mile radius of eight boat ramps, including Jefferson City, Hartsburg, Franklin Island, Glasgow, Miami, Waverly, Lexington, and La Benite . Biologists sampled these areas in 2022 and 2023 for larval sturgeon using benthic trawls (nets) that they pulled along the bottom. The path of the trawl was recorded using precise GPS to ensure that physical data were collected directly over the area that the trawls sampled. Biologists sampled with trawls along three paths per wing dike. The day after each area was trawled, USGS scientists surveyed the area with an acoustic Doppler current profiler (ADCP) and a multibeam sonar to map velocity, depth, and bedforms. Each of the eight sites were sampled and surveyed twice during for a total of sixteen surveys.  Flow during 2023 on the Missouri River was lower than last year during the same period, exposing the tops of many wing dikes and sand bars, resulting in challenging survey conditions on the river. 

Data from these surveys will be processed in the coming months and compiled with data from 2022.  Analyses of physical and hydraulic characteristics associated with larval sturgeon catches will provide an improved understanding of the mechanics of downstream dispersal and interception. Ultimately the results will be used to explain why some places along the river are AECs.

figure showing trawl paths
Trawl paths (in black) with intersecting ADCP transects and an underlying multibeam sonar map, showing bedforms, at the Hartsburg, Missouri site on June 6, 2023.    


Scientists Map Substrates on the Bottom of the Upper Missouri and Yellowstone Rivers

By: Tyrell Helmuth and Caroline Elliott

picture of Upper Missouri River badlands
A view of the Upper Missouri River badlands as seen from a USGS research vessel using sidescan sonar to map bed substrates in search of spawning habitat for the pallid sturgeon.

September 7, 2023

Scientists from the U.S. Geological Survey (USGS) Columbia Environmental Research Center (CERC) spent two weeks at the end of June mapping the dominant substrates on the bed of the Upper Missouri, Yellowstone, and Tongue Rivers in Montana and North Dakota. The mapping was conducted to locate habitat that may attract spawning pallid sturgeon. On the Upper Missouri River, substrates were mapped from the Fort Peck Reservoir spillway 189 miles downstream to the river’s confluence with the Yellowstone River. The Yellowstone River was mapped from Miles City, Montana 112 miles downstream to the Intake Fishing Access Site. In 2018, USGS scientists mapped substrates on the Yellowstone River from the Intake Fishing Access Site 73 miles downstream to the confluence of the Upper Missouri and Yellowstone Rivers. The maps completed this year provide scientists with 189 miles of substrate data for the entire Upper Missouri River downstream of Fort Peck Reservoir and the lower 185 miles Yellowstone River downstream from Miles City, Montana. This adds an important physical dataset to complement the large amount of pallid sturgeon telemetry tracking data that has been compiled over the years by state and federal scientists on both the Upper Missouri and Yellowstone Rivers.

photo of the Yellowstone River
Yellowstone River near the Kinsey Bridge upstream of the Fishing Access at Fallon, Montana.

This year, telemetry tagged pallid sturgeon were tracked, by both Montana Fish Wildlife & Parks (MTFWP), the Bureau of Reclamation, and USGS biologists using watercraft and an extensive passive receiver station network. For the first time, pallid sturgeon were detected moving up the Yellowstone River and into the Tongue River. USGS scientists, mapped riverbed substrates in the lower twenty-two miles of the Tongue River. Working with MTFWP biologists allowed the USGS scientists to map water depth and velocity transects in a one-mile reach where sturgeon were aggregating and potentially spawning. Biologists verified spawning through recapture of the female pallid sturgeon and larval sampling was conducted downstream of the suspected spawn site. Habitat mapping on the Tongue River provides a better understanding of the habitat that pallid sturgeon use during spawning.   

sonar image of Missouri River sand dunes
Humminbird Solix 10 side imaging sonar unit showing sand dunes on the bottom of the Missouri River near Wolfpoint, Montana.
image of sediment sample
Sediment sample collected from the Tongue River utilizing a pipe dredge.


Bedform mapping on the Missouri, Yellowstone and Tongue Rivers was accomplished using a Humminbird Solix 10 unit with a sidescan transducer. Nearly 400 miles of sidescan data were collected during the two weeks of mapping. A pipe dredge was used by USGS scientists in the Tongue River to sample the composition of the substrate in several places throughout the mapped spawning reach as a method of confirming the sidescan sonar data collected the day before. Substrate maps will give an idea of where pallid sturgeon may aggregate for future spawning events in the Upper Missouri, Yellowstone, and Tongue Rivers.







Experiments Begin in New Eco-flume at CERC

By: Brandon Samson, Kimberly Chojnacki, Robert Jacobson, Aaron DeLonay

May 26, 2023

This week marked a milestone in the development of laboratory capabilities to study the effects of flow and hydraulic variation on early-life-stage sturgeon at the USGS. For the past three years the USGS has worked with the Saint Anthony Fall Hydraulics Laboratory (SAFL), University of Minnesota on the design and construction of an advanced eco-flume (see previous blog, Eco-flume Arrives at CERC). The CERC Eco-flume was completed in early Spring 2023 and the first experiments began this week.

picture of the CERC ecoflume
The CERC Eco-flume in action, showing the low-turbulence paddle propulsion system and integrated turning veins that also function as heat exchangers to heat and cool the water.

On Wednesday, May 24 CERC scientists added 5,000 1 day-post-hatch (dph) free embryos into the flume (see previous blog post, Laboratory Studies Begin with Spawning). The downstream dispersal behavior of free embryos was studied with a range of water velocities provided by novel, low-turbulence paddles designed by SAFL engineers. The paddles are designed specifically to move water so free embryos and larvae can swim normally while preventing injury to these fragile early life stages. Mortality during the initial experiment was extremely low (0.2%), indicating that the flume is operating as designed. CERC scientists are using high-speed digital cameras to monitor downstream velocity of dispersing free embryos, document their swimming behaviors, and record their distribution with depth. Analysis of video data will use machine-learning techniques developed in collaboration with the University of Missouri, Department of Civil and Environmental Engineering.

picture of CERC Eco-flume paddle
Drifting one day-old pallid sturgeon free embryos swimming through the CERC Eco-flume as the paddle propulsion creates water current simulating the Missouri River.

Experiments with pallid sturgeon free embryos and larvae will continue through June 2023 with 5-, 8-, 11-, and 14-dph larvae. Studies will evaluate their swimming capability and innate behaviors and provide understanding on the effects of development on early life-stage dispersal. Later in 2023, CERC scientists will experiment with older larval and juvenile life stages, and with bedforms placed on the bottom of the flume to evaluate how natural roughness elements may slow dispersal.

picture of scientists watching video
Columbia Environmental Research Center and University of Missouri scientists evaluate video imagery of pallid sturgeon free embryo dispersing with the current during Eco-flume studies.

The motivating research questions driving the development of the Eco-flume at CERC have been linked with transport and fate of free embryos and larvae of the endangered pallid sturgeon. How far free embryos and larvae drift before they can hold themselves in the current and start feeding is a key variable in management decisions for the Missouri River supporting recovery of the species. In addition to studies with sturgeon, the flume will provide experimental capacity to study numerous species in flowing water, including other imperiled fluvial fish species, invasive carps, and native mussels.




Laboratory Studies Begin with Spawning   

By: Kimberly Chojnacki, Killian Kelly, Parker Golliglee, and Aaron DeLonay

photo of collecting ovulated eggs from a female pallid sturgeon
USGS scientists collect ovulated eggs from a female pallid sturgeon induced to spawn in the laboratory using artificial hormones.

May 18, 2023

The Comprehensive Sturgeon Research Project performs many studies each year with early life stage sturgeons. These include studies of genetics, development, biomechanics, behavior, and the development of new marking and tagging strategies. This requires CERC scientists and their partners at the USFWS Gavin’s Point National Fish Hatchery (GPNFH) to consistently spawn adult sturgeon in captivity to produce tens of thousands of sturgeon eggs, newly hatched free embryos, and larvae for planned research studies each year.

Both CERC and GPNFH maintain captive broodstock that are used to produce young sturgeon for research. On May 18, 2023 scientists at CERC artificially spawned adult pallid sturgeon broodstock to produce the young sturgeon needed to begin dispersal experiments in the new Eco-flume (see previous blog, Eco-flume Arrives at CERC). Three male and five female pallid sturgeon from the CERC captive broodstock were injected with hormones in the days preceding spawning. The injections were precisely timed so that the female sturgeon ovulate or release eggs early in the morning on the day of spawning.  Eggs were “stripped” by hand from the females at intervals of approximately one hour by applying gentle pressure to their abdomens and pushing downward toward their tail. The eggs were collected in shallow bowls and mixed with milt (sperm) collected from the males to fertilize the eggs. Fertilization was done in the dark. Fertilized eggs (embryos) were maintained in the dark for several hours before being transferred into hatching jars where they incubate for about 5 days before hatching.

photo of newly fertilized pallid sturgeon eggs
Newly fertilized pallid sturgeon eggs (embryos) are held in the dark in screened boxes floating in large tanks of temperature-controlled water until they are ready to be transferred to hatching jars for incubation.

Spawning on May 18 was unusually successful. The five females each produced between 45,000 to 63,000 eggs, for a total of about 260,000 eggs. The total weight of eggs produced by adult female sturgeon ranged from 11 to 17 percent of their bodyweight.  Fertilization rates determined within hours of spawning exceeded 95 percent. Scientists will monitor the development and hatch of the fertilized embryos for the next five days while preparing to begin experiments in the Eco-flume with 1-, 5-, 8-, 11-, and 14-day old pallid sturgeon.



photo of a scientist looking through a microscope
USGS scientist, Kimberly Chojnacki, examines newly fertilized eggs under a microscope to observe early development and estimate rates of fertilization.



CERC Scientists Facilitate Pallid Sturgeon Data Integration    

By: Kimberly ChojnackiParker Golliglee, and Chad Vishy

April 26, 2023

Informed management decisions to support recovery of the endangered pallid sturgeon in the Upper Missouri River Basin have been challenged by data integration. Multiple State, Federal, and University partners hold key information on capture locations, tagging, genetics, migrations, habitat use, and spawning. Each partner employs a range of different data collection, management, and reporting strategies. A team of scientists and data specialists from the USGS Comprehensive Sturgeon Research Project at CERC was funded by the Western Area Power Administration to assist in developing standardized data collection and submission processes to ensure that all partners are collecting a minimal set of compatible data to contribute to common research and monitoring needs.


The USGS Sturgeon Data Team met with State and Federal partners from the Upper Missouri and Lower Yellowstone Rivers in Williston, North Dakota, April 25–26, 2023, to determine data infrastructure and processes to facilitate rapid reporting of critical data for Pallid Sturgeon monitoring. Kimberly Chojnacki, Chad Vishy, and Parker Golliglee discussed potential areas for data enrichment, appropriate relational database architecture, and data sharing.  Based on input from partners within the basin, the Sturgeon Data Team analyzed the existing data streams and outlined critical data to develop a unified relational database architecture and to facilitate reporting of essential data to all partners The team used these data to demonstrate data-driven tools designed to assist in decision making, both in the office and in the field. 

photo of people around a table
USGS Biologist, Kimberly Chojnacki leads discussions on terminology and standardization of data collection.




Sediment Burial Reduces Sturgeon Embryo Survival and Hatch   

By: Kimberly Chojnacki, Killian Kelly, Parker Golliglee, and Aaron DeLonay

January 15, 2023

Researchers from the U.S. Geological Survey, Columbia Environmental Research Center (CERC) recently published the scientific article, “Effects of Substrate and Sediment Burial on Survival of Developing Pallid Sturgeon (Scaphirhynchus albus) and Shovelnose Sturgeon (S. platorynchus) Embryos” in the journal, Environmental Biology of Fishes. The endangered pallid sturgeon and common shovelnose sturgeon both spawn in flowing water, depositing their adhesive eggs on the river bottom, near or over coarse substrate (typically gravel and cobbles). Surveys have shown that the habitats where sturgeon spawn in the Missouri and Yellowstone Rivers are dynamic and that coarse substrates in these areas may be episodically buried by finer, mobile sediments, such as sand and silt (see previous blog, USGS Scientists Assess Pallid Sturgeon Spawning Habitat). Fine sediment can dislodge adhesive eggs of riverine species or bury them and deprive them of oxygen during incubation.

In this controlled laboratory study, researchers evaluated the survival of both pallid sturgeon and shovelnose sturgeon embryos (fertilized eggs) in various substrate conditions designed to simulate possible fates in a sand-bedded river. Newly fertilized embryos were allowed to develop on substrates of clean glass (control), gravel, medium-coarse sand, or fine sand-silt in aquaria for 10 days (5 days beyond expected onset of hatching). Embryos in aquaria with medium-coarse sand and fine sand-silt were tested with three different burial scenarios; unburied, partially buried, and fully buried. Embryos in partial burial treatments were uniformly covered by sediment without being fully buried. Embryos in the full burial treatments were completely covered to a depth of approximately 1–2 mm. For both species, hatch of normally developed free embryos was significantly reduced by burial in fine sediments. Results from this study indicate that these sturgeon species are intolerant of burial by even small amounts of mobile, fine sediment. Suitability of spawning and incubation habitats for endangered pallid sturgeon and shovelnose sturgeon may be dependent on river conditions that result in persistent patches of clean, coarse substrate.

photo of equipment in a laboratory
Photographs of (a) an array of experimental aquaria where fertilized embryos are developing with different types of sediment, and (b) view of embryos developing on medium-coarse sand and (c) fine sand-silt.





Revisit what happened in 2022 at the Comprehensive Sturgeon Research project.

Return to the Comprehensive Sturgeon Research Project Overview.

Return to River Studies.