Comprehensive Sturgeon Research Project Blog - 2019

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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. 

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New Genetic Technique to Identify Sturgeon Eggs

By Aaron DeLonay

December 20, 2019

 

Researchers from the U.S. Geological Survey, Comprehensive Sturgeon Research Project recently published the results of a study conducted in collaboration with scientists at Southern Illinois University.  The scientific journal article, "Improved Genetic Identification of Acipenseriform Embryos with Application to the Endangered Pallid Sturgeon Scaphirhynchus albus," authored by Dr. Tom Kashiwagi and others, was published in the Journal of Fish Biology.  The principal study investigators are from Dr. Edward Heist's laboratory at the Center for Fisheries Aquaculture and Aquatic Sciences at Southern Illinois University Carbondale.  The results of this study describe techniques to genetically identify developing acipenseriform embryos (sturgeons and paddlefish) before they hatch.  Researchers at SIU were able to genetically identify pallid sturgeon embryos to species and assign parentage within about 24 hours after egg fertilization (developmental stage 14).  The techniques described are important advances for the conservation of all sturgeon, including the endangered pallid sturgeon.  Researchers are now better able to define and monitor spawning of imperiled sturgeons in response to habitat conditions, environmental cues, and management actions.

Select developmental stages of pallid sturgeon (Scaphirhynchus albus) embryos reared in the laboratory

Select developmental stages of pallid sturgeon (Scaphirhynchus albus) embryos reared in the laboratory at a mean temperature of 18.2 degrees Celsius.  New genetic techniques can identify pallid sturgeon as early as Stage 14; about 24 hours after spawning and fertilization.

(Credit: Marlene Dodson, U.S. Geological Survey. Public domain.)

The genetic analyses for this study were funded by the Western Area Power Administration (WAPA) through the Upper Basin Pallid Sturgeon Workgroup.  The USGS provided the laboratory production and staging of pallid sturgeon embryos, and the field collection of Acipenseriform embryos through the Comprehensive Sturgeon Research Project funded by the U.S. Army Corps of Engineers, Missouri River Recovery–Integrated Science Program.

 

Citation:  Kashiwagi, T., DeLonay, A.J., Braaten, P.J., Chojnacki, K.A., Gocker, R.M. and Heist, E.J. (2019), Improved genetic identification of acipenseriform embryos with application to the endangered pallid sturgeon Scaphirhynchus albus. J Fish Biol. http://dx.doi.org/10.1111/jfb.14230

 

 

Remotely Monitoring Pallid Sturgeon Movement in Real Time

By Aaron DeLonay and Chad Vishy

December 17, 2019

 

Radio telemetry station hardware enhancement configured to insert into existing environmental enclosure

Radio telemetry station hardware enhancement configured to insert into existing
environmental enclosure, including radio receiver, antenna switch, cellular modem 
signal booster, and Windows-based mini-computer. (Public domain.)

During the summer of 2019, scientists at the Columbia Environmental Research Center developed hardware and software solutions to enhance the communication capability of data-logging radio receivers used to detect pallid sturgeon implanted with transmitters in the Lower Yellowstone and Upper Missouri Rivers.  The new remote communication capabilities developed for passive radio-telemetry receiver stations were installed and tested at a single location on the Lower Yellowstone River immediately downstream from a known spawning location (see previous blog entry A Spawning Recorded in the Yellowstone River). 

Radio telemetry receiver station with enhanced communication capability installed with sealed 12-volt batteries and solar panel

Radio telemetry receiver station with enhanced communication
capability installed with sealed 12-volt batteries and solar panel
charge controller. (Public domain.)

The new equipment was designed to be installed within the environmental enclosure of existing telemetry stations.  The improved telemetry stations can use cellular or satellite-based technology to upload data from the receiver to a remote server twice per day.  The receiver station can also be remotely queried hourly to receive updates on fish detection and movement.  The technology is ready for broad application at designated telemetry network sites as needed in 2020 to provide near real-time fish movement data to study migration and spawning in response to environmental cues and management actions.

Solar-powered radio telemetry station installed on the bank of the Lower Yellowstone River with two Yagi antennas

Solar-powered radio telemetry station installed on the bank of the Lower Yellowstone River with
two Yagi antennas monitoring upstream and downstream movement of pallid sturgeon.
(Public domain.)

 

Nebraska Game and Parks Biologist, Christine Bender samples blood from adult pallid sturgeon to assess fish condition

Nebraska Game and Parks Biologist, Christine Bender samples blood from adult pallid sturgeon to assess fish condition during telemetry tagging efforts at the USFWS Gavins Point National Fish Hatchery.

(Credit: Ross Burlbaw, U.S. Geological Survey. Public domain.)

A Good Start to Renewed Telemetry Efforts on the Lower Missouri River

By Marlene Dodson, Killian Kelly, and Aaron DeLonay

November 4, 2019

 

The USGS in collaboration with the Nebraska Game and Parks Commission (NGPC) and the U.S. Fish and Wildlife Service (USFWS) assisted in the tagging and transfer of adult pallid sturgeon collected for broodstock and held at USFWS Neosho National Fish Hatchery and USFWS Gavins Point National Fish Hatchery back to the Lower Missouri River on Thursday and Friday, October 24th and 25th, 2019. USGS biologists and a fish transport truck retrieved two pallid sturgeon and one pallid x shovelnose sturgeon hybrid on Thursday morning from the USFWS Neosho National Fish Hatchery and returned them with transmitters to the nearest boat ramp to the point of original capture (Waverly and Cooley Lake, Missouri).  On Friday morning at 8:00 AM, USGS biologists met NGPC biologists with two fish transport trucks at the USFWS Gavins Point National Fish Hatchery to implant 12 additional pallid sturgeon with transmitters.  Surgical procedures included the implantation of acoustic transmitters, visual identification of sex and reproductive stage, blood collection for sex and reproductive stage, and egg biopsies, for reproductive females.  In addition, reproductively cycling sturgeon of known sex weighing greater than 3.0 kilograms received an archival data storage tag (DST) programmed to record depth (as pressure) and temperature.  Blood was also taken in cooperation with fish condition studies by Montana State University and Bozeman Fish Technical Center.  Surgeries were completed by noon.  The three trucks returned all fish to the Missouri River at the boat ramp nearest to their point of original capture by 8:00 pm.

Pallid sturgeon used in the propagation program and subsequently conditioned before release at participating hatcheries are extremely valuable fish for the evaluation of spawning success and response to environmental cues, such as flows or temperature.  A total of 12 of the 15 implanted sturgeon are of known sex and are reproductively cycling with known recent spawning histories.  Six of the pallid sturgeon implanted at Gavins Point National Fish Hatchery were early stage IV, black egg females.  There is now a total of seven possible reproductive females for 2020 with transmitters, including a hatchery-origin female implanted earlier in the fall by NGPC biologists.  The seven females are spread through the river between St. Joseph, Missouri and Yankton, South Dakota.   Several of the males will likely be reproductive as well, though male readiness is more difficult to determine this far out from spawning season.  In comparison to previous years’ studies, this is a substantial early surge in the number of fish available to respond to environmental cues for spring of 2020.

Nebraska Game and Parks Biologist, Ryan Ruskamp examines an adult pallid sturgeon to determine sex and reproductive condition

Nebraska Game and Parks Biologist, Ryan Ruskamp examines an adult pallid sturgeon to determine sex and reproductive condition during telemetry tagging efforts at the USFWS Gavins Point National Fish Hatchery

(Credit: Ross Burlbaw, U.S. Geological Survey. Public domain.)

 

 

Eat or Be Eaten

By Marlene Dodson

October 28, 2019

 

Adult pallid sturgeon are large river predators and an important portion of their diet consists of other small fishes.  Few other fish pose a threat to adult pallid sturgeon.  Newly hatched pallid sturgeon, on the other hand, are at risk of being eaten by most all other fishes.  Predation is one of many factors that affects survival of young fishes.  Although it is a normal process, some species may be more vulnerable to predators when habitats are altered.  Large mainstem dams have reduced the turbidity in many segments of the pallid sturgeon’s former habitat.  For a species, like the pallid sturgeon, that evolved to drift long distances downstream as a free embryo, a less turbid, clearer river might allow predators to prey on them easier.

Adult emerald shiners are shown feeding on shovelnose sturgeon free embryos during preliminary predation experiments

Adult emerald shiners are shown feeding on shovelnose sturgeon free embryos during preliminary
predation experiments conducted at the Columbia Environmental Research Center. (Public domain.)

In the spring of 2019, Comprehensive Sturgeon Research Project scientists conducted preliminary studies to determine if the emerald shiner, a sight-feeding predator that often increases in rivers when turbidity declines, could effectively eat young sturgeon.  Predation trials were conducted with 0–7 days post-hatch shovelnose sturgeon and adult emerald shiners.  Shovelnose sturgeon are used as a surrogate for pallid sturgeon in some of our studies since the two species are similar during the free-embryo and larvae stages.  A minimum of 25 shovelnose sturgeon free embryos were placed in a tank daily with seven emerald shiners beginning on the day of hatch up until the emerald shiners failed to show interest in eating the young sturgeon.  Predation attempts by emerald shiners were recorded using a video camera placed in front of the tank.  Adult emerald shiners were able to effectively capture and ingest young sturgeon until they reached about eight days post hatch.  The video shown above is of shovelnose sturgeon at three days post hatch.

 

 

Training Sturgeon Surgeons

By Aaron DeLonay and Casey Hickcox

October 17, 2019

 

With the implementation of the new Missouri River Science and Adaptive Management Plan many of the telemetry research activities developed by the Comprehensive Sturgeon Research Project (CSRP) on the Lower Missouri River will be expanded and included in the revised Pallid Sturgeon Population Assessment Program (PSPAP 2.0).  The technologies and techniques used to capture, assess, tag, and track sturgeon will be transferred to other participating state and federal agencies.  Disseminating this technology requires not only equipment but training as well.

USGS biologist demonstrates surgical techniques for pallid sturgeon during training

USGS biologist demonstrates surgical techniques for pallid sturgeon during
training at the Columbia Environmental Research Center.
(Credit: Aaron DeLonay, U.S. Geological Survey. Public domain.)

In total, more than 20 biologists from the U.S. Army Corps of Engineers, Nebraska Game and Parks Commission, Missouri Department of Conservation, and the U.S. Fish and Wildlife Service came to the USGS Columbia Environmental Research Center for two intensive days of classroom instruction and on-the-water training. The participants spent a day in the classroom focusing on telemetry essentials, surgical transmitter implantation techniques, reproductive assessment of sturgeon, collection of blood for sex steroid profiles, and minimally invasive biopsy techniques to collect eggs from reproductive females.  The second day was spent on USGS research tracking boats on the Missouri River becoming familiar with new acoustic telemetry receivers, hydrophones, and transmitters.  The river was higher than usual during training and the muddy, turbulent water flowing through the complex habitats of Searcys Bend illustrated to students the unique challenges of telemetry in the Lower Missouri River.  River levels will drop eventually and telemetry will get a bit easier but these times when equipment and techniques are pushed to their limits provide an excellent training opportunity.  We thank all those who joined us for this training and anticipate more training in the year ahead as all agencies implement telemetry technologies to monitor pallid sturgeon populations.

Biologists from the Missouri Department of Conservation learn to identify the sex of pallid sturgeon using ultrasound

Biologists from the Missouri Department of Conservation
learn to identify the sex of pallid sturgeon using ultrasound
during training at the USGS Columbia Environmental Research
Center.
(Credit: Aaron DeLonay, U.S. Geological Survey. Public domain.)

 

 

A Nine Week Search for Baby Pallid Sturgeon

By Colt Holley

September 3, 2019

Biologist Dr. Pat Braaten and Habitat technician Jared Hintz lower a beam trawl into the Upper Missouri River

USGS Biologist Pat Braaten, Ph.D., and Jared Hintz, Habitat technician, lower a beam
trawl into the Missouri River to sample for settled pallid sturgeon larvae.
(Credit: Colt Holley, U.S. Geological Survey. Public domain.)

The USGS recently collaborated with Montana Fish, Wildlife and Parks, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service personnel in a trawling effort to search for settled pallid sturgeon larvae after nearly 1,000,000 free embryos were released 150 miles upstream. This effort was part of the 2019 larvae drift experiment which began July 1st (see previous blog Unprecedented Pallid Sturgeon Larval Drift Experiment) on the Missouri River from river mile 1701 near Wolf Point, MT downstream to the headwaters of Lake Sakakawea at river mile 1550 near Williston, ND. The trawling followed an intensive 8-day nearly around-the-clock sampling effort to capture drifting free embryos that were released upstream (See previous blog Down to the Bottom, and Back Again…and Again).

A 37-mm larval sturgeon captured in the Missouri River near Fort Buford, Montana.

A 37-mm sturgeon larva captured in the Missouri River near Fort Buford, Montana.

(Credit: Colt Holley, U.S. Geological Survey. Public domain.)

From July 16 through September 11, a beam trawl was used to sample benthic habitats for settled pallid sturgeon larvae. The setup consists of a pair of tapered nets (outer coarse net, inner fine-meshed net) attached to a steel beam and frame. The beam trawl is lowered over the bow before the boat reverses downstream, dragging the net along the substrate. This process agitates the substrate and is used to target young-of-year benthic fishes. Sampling occurred at several river bends of the Missouri River upstream and downstream from the confluence of the Yellowstone River in western North Dakota and eastern Montana. At each bend, the trawl was deployed in various macrohabitats and at various depths to determine locations where settled pallid sturgeon larvae were present.

A presumed shovelnose sturgeon (left) and presumed pallid sturgeon (right), pending genetic analysis.

A presumed shovelnose sturgeon (left) and presumed pallid
sturgeon (right), pending genetic analysis, that were collected
during trawling. (Credit: Tyler Haddix, Montana Fish, Wildlife
and Parks. Public domain.)

More than 700 sturgeon larvae were sampled over the 9-week sampling period. At very small sizes, pallid sturgeon and shovelnose sturgeon are visually indistinguishable. As the larvae grow, some characteristics such as the length and positioning of the barbels start to differ between young pallid and shovelnose sturgeon.  Given the similarity between larvae of the two sturgeon species, genetic analysis is conducted on tissue from all collected specimen to differentiate them as pallid or shovelnose sturgeon. 

 

This experiment is part of an ongoing study on the federally endangered pallid sturgeon to determine factors associated with decades of recruitment failure. It is hypothesized that pallid sturgeon free embryos (the first life stage after hatching) disperse in the river currents for several days and require many miles of free-flowing river habitat prior to developing into benthic-oriented larvae.

 

 

Tracking Down the Wide Missouri

By Aaron DeLonay and Casey Hickcox

August 2, 2019

 

This week, biologists and technicians from the USGS Columbia Environmental Research Center joined with colleagues at the Nebraska Game and Parks Commission to complete an intensive telemetry tracking effort of the entire 811-mile stretch of the Lower Missouri River from Gavins Point Dam at Yankton, South Dakota to the confluence of the Missouri and Mississippi Rivers, near St Louis, Missouri.  Pallid sturgeon can move long distances.  Both agencies simultaneously and methodically searching the length of Lower Missouri River provided the biologists the best chance at detecting fish before they could move into previously-tracked reaches and escape detection.  The mission was to locate all telemetry tagged sturgeon with active transmitters in the Lower Missouri River.  In total, the collaborative effort took approximately two weeks to complete.

A USGS research vessel testing acoustic telemetry equipment on the Lower Missouri River

A USGS research vessel testing acoustic telemetry equipment on the Lower Missouri River with biologists from the Nebraska Game and Parks Commission.  These research vessels track telemetry-tagged pallid sturgeon in the 811 miles of the Lower Missouri River from Gavins Point Dam, South Dakota to the confluence with the Mississippi River at St. Louis, Missouri.

(Public domain.)

The USGS tracking boats searched the lower 425 miles from Atchison, Kansas downstream to St. Louis, Missouri.  The river is wider downstream and the flows were higher than usual.  Under these conditions the river is searched using two pairs of tracking boats.  Each pair of boats searches a segment of river 25 to 40 miles long with the boats tracking in tandem (one boat along each river bank).  Tracking boats looking for pallid sturgeon tagged with acoustic transmitters search downstream at about 6 miles per hour with hydrophones in the water listening for transmitters. 

Despite the high water, biologists were able to locate 28 pallid sturgeon.  Most tagged sturgeon were located in the upstream 400 miles of river.  While some tags have expired since intensive tracking was last conducted on the Lower Missouri River, scientists now have a river-wide perspective of the number of pallid sturgeon with active transmitters and where those pallid sturgeon were during the high water of late summer 2019.  More sturgeon will be implanted with transmitters in the fall of 2019 and the spring of 2020.  Many of the sturgeon with active transmitters that biologists found during this search will be located again and recaptured to replace tags and assess their reproductive condition.  Knowing where these sturgeon are now will help give scientists a head start on spring recapture attempts.

 

 

Down to the Bottom, and Back Again…and Again.

July 20, 2019

A larval sampling crew photographed from an accompanying sampling boat through the fog just after dawn

A larval sampling crew photographed from an accompanying sampling boat through the fog just after dawn on the Upper Missouri River. (Public domain.)

When the sturgeon larvae went into the water on July 1st, the drift experiment was underway. There was no undo button, do-overs, or alternate endings. Each step in the experiment needed to be executed with precision.  The results were dependent upon the ability of sampling crews comprised of university, and state and federal agency biologists to track and then sample those groups of free embryo pallid sturgeon as they moved downstream through 150 miles of river. Drift models that had been in development for years were dependent upon it – and the crews were up to the task.

A biological technician retrieves a sample from one of two, paired fine-mesh (1000 micron) ichthyoplankton nets

A biological technician retrieves a sample from one of two, paired fine-mesh (1000 micron)
ichthyoplankton nets weighted with 100-pound lead weights to sample pallid sturgeon
free-embryos as they drift downstream near the bottom. (Public domain.)

Through cold rainy nights and hot sunny days, crews spent 8 days sampling the Upper Missouri River from the release point near Wolf Point, Montana, to the headwaters of Lake Sakakawea near Williston, North Dakota. Working in 12-hour shifts, multiple alternating crews provided round-the-clock sampling to map the movement of the sturgeon larvae as they traversed the stretches of river. Using water velocities and hydraulic models developed from previous drift studies (See previous blog post, 700,000 Baby Fish), Comprehensive Sturgeon Research Project (CSRP) scientists provided projections of drift times to guide the deployment of larval sampling boats to track the mass of sturgeon as they moved downriver. Those models were crucial to ensure that sampling crews were in place and sampling before the sturgeon free embryos passed each of the six designated sampling sites along the 150-mile trek. Boats were in their designated sampling locations before the first larvae were projected to arrive and left only after sturgeon free embryos were no longer detected.  Sampling before arrival allows scientist to estimate any background natural reproduction of shovelnose sturgeon or paddlefish.  Sampling after the mass of sturgeon passed allows scientists to model how the mass of free embryos spreads out through time (dispersion).

Biological technicians with the USGS sort through ichthyoplankton net samples searching for free-embryo pallid sturgeon

Biological technicians with the USGS sort through ichthyoplankton net samples searching for free-embryo pallid sturgeon from the experimental larvae release shortly after midnight. (Credit: Chad Vishy, U.S. Geological Survey. Public domain.)

Boats sampled for the drifting free embryos using fine-mesh ichthyoplankton nets suspended just above the river bottom where most pallid sturgeon are believed to drift. Biologists also sampled at the surface and in the middle of the water column each hour to validate that assumption. The objective was to collect as many samples as possible during the 12-hour shift.  All boats were equipped with a pair of nets; one suspended off either side. Biologists would lower their nets with lead weights using a winch near the bottom, allow them to sample for a designated period, then retrieve the nets and sift through the nets’ contents using forceps. Free-embryo sturgeon are only about 6 to 20 millimeters.  Biologists needed to maintain focus during the long hours to give the painstaking attention needed to every leaf and twig to ensure each specimen was counted and preserved.

USGS larval sampling boats wait out a fast approaching thunderstorm before deploying nets in the Upper Missouri River

USGS larval sampling boats wait out a fast approaching thunderstorm before deploying nets in the Upper Missouri River to collect drifting pallid sturgeon free embryos. (Credit: Chad Vishy, U.S. Geological Survey. Public domain.)

The preserved free embryos will be sent back to CERC to be measured and their developmental stages determined. Then they will be prepared for genetic analyses to verify species and to confirm that the parentage of each specimen can be traced back to the adult broodstock parents spawned for this experiment in the hatchery. Scientists expect the data from this experiment to be invaluable to efforts to continue advancing their knowledge and understanding of larval drift and refining critical multi-dimensional hydraulic models to test hypotheses and guide management actions (see previous blog post, Fine-scale Mapping of the Complex Upper Missouri River - Phase Two).

 

An Improved Space for Better Science

By Marlene Dodson

July 18, 2019

 

In our 2018 Blog post “Improving lab capabilities at CERC” we previewed renovations in a new space that would greatly benefit the studies we do with pallid sturgeon early life stages. After demolition, construction, plumbing and wiring, things have come together quite well.  

In the spring of 2019, Comprehensive Sturgeon Research Project scientists hatched the first pallid sturgeon in the new rearing facilities in the new space.  A batch of approximately 124,000 pallid sturgeon free embryos from six different family crosses were incubated and hatched in three new, partially recirculating incubation systems. These free embryos became the foundation for our laboratory studies that were conducted this spring.  

A set of 6 three-foot tanks used for larval and juvenile sturgeon, and one of our new incubation systems

A set of 6 three-foot tanks used for larval and juvenile sturgeon, and one of our
new incubation systems in the new research space. (Public domain.)

This new space allows us to conduct multiple concurrent studies (including our mass marking study) by increasing our ability to propagate, incubate, hatch, and hold sturgeon.  While the new and improved incubation systems provided a great start to life for newly hatched sturgeon, a new battery of tanks provided greater capacity to support feeding larvae and juveniles, and larger eight-foot and ten-foot holding tanks allowed us to bring our adult broodstock from outside ponds closer for better environmental control before spawning.  The building is also a bio-secure facility where access to fish is restricted and all water leaving the facility is treated to prevent the release of organisms or diseases into the surrounding environment.

Shovelnose sturgeon eggs incubating in hatching jars for spring 2019 genetic studies.

Shovelnose sturgeon eggs incubating in hatching jars for spring 2019 genetic studies.
(Public domain.)

The ability to work with the earliest stages of pallid sturgeon is critical to resolving many of the science information needs of managers and stakeholders working to improve survival and growth of populations in the river.  This capability is key to the success of studies planned for a newly constructed hydraulic flume at CERC intended to study early life stage sturgeon under simulated river conditions set to be completed in 2021.

 

 

An Eggcellent Spawning Season

Eggs in 10% neutral buffered formalin showing the germinal vesicle

Eggs preserved in 10% neutral buffered formalin showing the germinal vesicle close to the animal pole. This fish was ready to spawn.

(Public domain.)

By Marlene Dodson, Aaron DeLonay, and Killian Kelly

July 8, 2019

 

Spring has sprung and the eggs are on their way.

We maintain a small population of adult pallid sturgeon here at the Columbia Environmental Research Center for use in laboratory studies.  The start of the spring laboratory season begins with checking reproductive female sturgeon to determine if they are ready to spawn. This includes collecting eggs from female pallid sturgeon through a small incision or using a special syringe during a minimally invasive procedure or biopsy.  The eggs from this biopsy are preserved in 10 percent neutral buffered formalin for 24 hours to harden before they can be examined for maturity.  Once hardened, we delicately slice the preserved eggs in half to determine a polarity index. The polarity index is the ratio of the distance of the germinal vesicle to the animal pole (one end of the egg) to the total diameter of the egg. As the germinal vesicle nears the animal pole, the polarity index falls below 0.1 and the biologists know that the eggs are mature, and the female is ready to spawn.

Developing pallid sturgeon embryos rolling in a McDonald hatching jar.

Developing pallid sturgeon embryos rolling in a McDonald hatching jar.

(Public domain.)

When the eggs are mature and the female is ready to spawn, she is injected with luteinizing hormone-releasing hormone(LHRH) and white sturgeon pituitary extract in two injections 12 hours apart.  The hormones  cause the eggs to ovulate and release from the female’s ovaries.  The ovulated eggs can be expressed from the female’s body by hand at hourly intervals using light brushing strokes along her abdomen, or the biologist can make a small incision and remove all the eggs at once.  The male sturgeon were also injected with LHRH to cause them to produce milt the day before the females ovulate.  The milt was collected from the males using a syringe with flexible tubing inserted a small distance into the male’s vent.  The milt is examined and graded under a microscope the day before spawning is scheduled in the laboratory to make sure that it is viable before it is used to fertilize eggs.   The milt is stored in refrigerated oxygenated bags overnight.

During artificial spawning in the laboratory, eggs collected from the female are immediately fertilized with milt from multiple reproductive male fish.  Eggs and milt are artificially collected and combined in a bowl, and water is added to activate the sperm cells in the milt.  The magic of fertilization is complete within minutes. The fertilized eggs are water hardened in a temperature-controlled pool before being transferred to McDonald-type hatching jars and incubated until hatch. This year the embryos, fertilized eggs, and hatched free embryos were used for studies investigating the effects of sand abrasion on egg and larva survival, the development of methods to mass mark free embryo and sturgeon larva for field studies of transport, retention and survival, and for use in studies of sturgeon genetics.

 

 

Unprecedented Pallid Sturgeon Larval Drift Experiment

By Robb Jacobson, Aaron DeLonay, and Casey Hickcox

July 1

USGS Biologist Pat Braaten, Ph.D., briefs crews prior to the release of larval pallid sturgeon on the Upper Missouri River.

USGS Biologist Pat Braaten, Ph.D., briefs crews prior to the release of pallid
sturgeon larvae on the Upper Missouri River. (Public domain.)

Scientists with the Columbia Environmental Research Center (CERC) collaborated with the U.S. Army Corps of Engineers; U.S. Fish and Wildlife Service; Montana Fish, Wildlife and Parks; and Southern Illinois University scientists in early July to carry out a larval drift experiment of unprecedented scale and complexity.  The experiment involved the release of over 1 million, genetically distinct larval pallid sturgeon, ranging 1 to 5 days old.  The experimental results are fundamental for calibrating biological-hydraulic models of drift and dispersal of pallid sturgeon larvae on the Upper Missouri River, Montana. The dominant hypothesis for recruitment failure of the critically endangered pallid sturgeon on the Upper Missouri River is insufficient drift distance between Fort Peck Dam and Lake Sakakawea.

Biologists unload coolers full of larval pallid sturgeon after transport from the hatchery

Biologists unload coolers full of pallid sturgeon larvae after transport from the
Garrison National Fish Hatchery. (Public domain.)

The planning for the 2019 Upper Missouri River study was several years in the making.  Data collection began in 2018 and continued through 2019 as USGS scientists spent weeks intensively mapping the depth, water velocity, and elevation of the sand bars and river banks along a 36 kilometer reach of the braided river between Wolf Point and Poplar, Montana where the experiment was to happen.  The survey data will be used to create high-resolution hydrodynamic and particle-tracking models to understand how downstream dispersing free embryo sturgeon are distributed through the reach, and how far and how fast they are expected to travel.

A USGS biologist tests water temperatures to ensure proper acclimation for larval pallid sturgeon

A USGS biologist tests water temperatures to ensure proper acclimation for 
pallid sturgeon larvae before their release into the Upper Missouri River.  (Public domain.)

A year of planning meetings, data collection, broodstock collection, and hatchery efforts culminated in an early afternoon congregation on the north bank of the Missouri River near a boat ramp in Wolf Point, Montana.  A half dozen boats and two dozen biologists received their final instructions while awaiting the truck from Garrison National Fish Hatchery laden with coolers packed with 80 bags of oxygenated water carrying free-embryo pallid sturgeon for the experiment.  Upon arrival, coolers were loaded into boats, the boats moved out into the water and anchored across the width of the river.  The fish in the coolers were slowly acclimated to the river temperature and when the signal was given all the boats simultaneously released the young sturgeon.  In the end, the event went off without a hitch. Approximately 850,000 day-old and 225,000 five-day-old pallid sturgeon larvae were released into the waters. 

Biologists from the U.S. Geological Survey, U.S. Fish and Wildlfie Service, Montana Fish Wildlife and Parks and SIU

Biologists from the U.S. Geological Survey; U.S. Fish and Wildlfie Service; Montana
Fish, Wildlife and Parks; and Southern Illinois University anchor their boats across
the channel of the Missouri River waiting for the signal to release more than 1
million pallid sturgeon larvae. (Public domain.)

Over the next week, 8 boats and as many as 2 dozen scientists and technicians will work around the clock exhaustively sampling to track the downstream transport and fate of the larvae to the headwaters of Lake Sakakawea near Williston, ND.

 

 

Fine-scale Mapping of the Complex Upper Missouri River - Phase Two

June 25, 2019

 

When it comes to a river like the Mighty Missouri, only sometimes does the river reveal its complexity above the surface. While some areas will be littered with visible sandbars, they often hide below calm water undiscernible from the four-meter-deep channel that might run alongside. These are important details for scientists trying to navigate and study the river (for more on those hazards, see previous blog post Boating the Upper Missouri River is not for the faint of heart) but also crucial when trying to understand how, where, and why the newly hatched pallid sturgeon larvae utilize the dynamic conditions present throughout the dispersal stages of their development.

To better understand these complexities, hydrologists are completing the second half of an intensive mapping campaign that began with two weeks of hydroacoustic data collection in early June 2018. This year’s mapping effort just downstream from the Wolf Point, Montana, boat ramp will terminate at the upstream end of the 22 kilometers they mapped in 2018 near Poplar, MT. In total, high-resolution mapping will be completed over 36 kilometers and the upstream boundary will coincide with the location where free embryos are released for the 2019 Drift and Dispersal study.

River depths of the Upper Missouri River as mapped by CSRP hydrologist

River depths of the Upper Missouri River as mapped by CSRP hydrologists in support of the 2019 larval drift study.

(Public domain.)

Crews will continue to mimic the 2018 work by driving transects at 15-meter intervals using acoustic Doppler current profilers and single-beam echosounders to comprehensively map the braided riverway. In addition to the bathymetric data, the crew will be surveying river banks with a portable LiDAR system (See previous blog post, Mapping the river with lasers). Side channels, backwater pools, and other areas of potential stagnation are being given special attention as it is believed they could be important factors in drifting larvae survival. 

A digital elevation model of the Upper Missouri River

A digital elevation model of the Upper Missouri River as mapped by CSRP hydrologists in support of the 2019 larval drift study. 

(Public domain.)

The data collected will be used to extend and refine high-resolution particle tracking models to better understand how free embryos interact with the complex riverine environment.  While the fish and environment of the Missouri River may be difficult to study, these models can prove invaluable in informing future efforts and identifying existing knowledge gaps.

 

 

Growing and Still Glowing

By Killian Kelly

May 21, 2019

Young pallid sturgeon marked with calcein at 7 to 10 days post hatch shown under natural light and with marked structures

Young pallid sturgeon marked with calcein at 7 to 10 days post hatch shown under natural light and with
marked structures fluorescing under a UV light 5 to 25 days after marking. (Public domain.)

In the spring and summer of 2018, Comprehensive Sturgeon Research Project (CSRP) biologists developed methods to mark very young sturgeon to monitor dispersal, growth and survival in the river (See previous blog post, Here we glow!).  The challenge for biologists is that the free-embryos and sturgeon larvae are too small for traditional marking methods used in mark and recapture events.  One way to mark very young sturgeon is to use a chemical mark which would bind with calcified structures such as mouth parts, fin rays, or scutes and then fluoresce, or glow, when exposed to a special ultraviolet (UV) light.  Following successful 2018 studies with calcein showing that young sturgeon can be effectively chemically marked, researchers wanted to know the earliest age that a pallid sturgeon could be marked and how long they would retain a mark that could be detected by biologists in the field.

Biological science technician, Marlene Dodson, collects water quality data while marking pallid sturgeon free embryos.

Biological science technician, Marlene Dodson,
collects water quality data while marking pallid
sturgeon free embryos with calcein. (Public domain.)

This year (2019) CSRP biologists marked free-embryo pallid sturgeon by immersing them in a dilute calcein solution (0.5%) for 3 to 6 minutes.  To determine how early young sturgeon would retain a chemical mark, young sturgeon were marked in batches starting at 7 days post hatch (DPH).  New groups were marked daily until the sturgeon reached the age of 12 DPH, or approximately the age when they first begin to feed.  Biologists examined the sturgeon for a fluorescent chemical mark 5 days after treatment in the laboratory using a microscope equipped with a UV light source, and with a UV flashlight and special glasses that biologists can use in the field.  To determine how long the free-embryo sturgeon retained the fluorescent mark biologists immersed groups of sturgeon at 10 DPH in the calcein solution and monitored them for chemical marks every 5 days until the fish reached the age of 35 DPH.  Results of this study will be used to provide a way for biologists studying very young sturgeon in natural and constructed habitats in the Missouri River to monitor and track their dispersal, retention, growth and survival.

 

All Hands On Deck

May 12, 2019

Biologists from the Comprehensive Sturgeon Research Project (CSRP) from the Columbia Environmental Research Center (CERC) in Columbia, Missouri traveled to North Dakota in early May to assist in intensive pallid sturgeon broodstock recapture efforts in the Upper Missouri and Lower Yellowstone River.  Crews from USGS CERC added to the combined efforts of the USGS Fort Peck Project Office, U.S. Fish and Wildlife Service, and Montana Fish, Wildlife and Parks to attempt to recapture up to ten large gravid (ready to reproduce) females known to inhabit the Upper Missouri River and its tributaries.  Reproductive females are very rare in this river segment and multiple agencies scout the river each spring to collect them to produce young sturgeon in hatcheries to increase population numbers.  This year the effort was different.  The adult sturgeon were needed to produce newly hatched free embryos for a large experiment designed to study downstream drift and dispersal during the first weeks after hatch.  This study, several years in planning, will be larger and more intensive than a similar previous study in 2016 (See previous blog post, 700,000 Baby Fish).

USGS biologist Colt Holley prepares to release an adult pallid sturgeon

USGS biologist Colt Holley prepares to release an adult pallid
sturgeon after capture. (Public domain.)

Many of the adult pallid sturgeon have radio transmitters and can be located as they move upstream out of Lake Sakakawea, but not all of them. The large gravid females were essential to locate if plans were to proceed as planned due to the number of free embryos needed.  The previous drift study released 750,000 free embryos in 2016. The study in 2019 is expected to release more than one million free-embryo pallid sturgeon.  While some smaller females typical of the Lower Missouri River often produce 10-20,000 eggs, the larger, older fish from the Upper Missouri and Yellowstone Rivers may produce 100-150,000 eggs each.  Once the adult sturgeon are captured there are many variables that can influence the success of artificial spawning in the hatchery and reduce the number of viable larvae hatched.  Each reproductive female was precious.

Pallid sturgeon are marked with small PIT (passive integrated transponder) tags injected under the base of the dorsal fin.

Pallid sturgeon are marked with small PIT (passive integrated
transponder) tags injected under the base of the dorsal fin.  The
tags can be read with a special electronic reader that displays the
10-digit code that uniquely identifies the sturgeon. (Public domain.)

Early broodstock collection efforts resulted in few captured fish. The Missouri River, tributaries, and reservoirs are large, the fish are often unpredictable, and water conditions sometimes unfavorable. Still, four large gravid females were captured and shipped in a large tank truck to Garrison National Fish Hatchery in the first week.  Unseasonably cold weather slowed migration of adult sturgeon upstream out of Lake Sakakawea after the first week and resulted in fewer than expected opportunities to capture sturgeon.  The Columbia CSRP biologists returned to Missouri in mid-May while combined efforts of the other partners continued.  Biologists were ultimately able to locate another large gravid female, for a total of five wild pallid sturgeon females.  Additional adult pallid sturgeon from the captive broodstock population at Gavins Point National Fish Hatchery will be used to produce the remaining needed free embryos for the experiment.  The current forecast is that participating hatcheries will be able to provide around one million one- and five-day old free embryos for the experimental release in early July.

 

 

Scientists from the Columbia Environmental Research Center have been back on the outreach trail recently with two great Missouri River Relief hosted events.

April 24, 2019

CERC Ecologist Casey Hickcox explains Missouri River science

CERC Ecologist Casey Hickcox explains Missouri River science to participants at Missouri River Relief's 2019 Washington River Festival in Washington, Missouri.

(Credit: Aaron DeLonay. Public domain.)

 

 

 

On April 13th, scientists operated an informational booth at the Washington River Festival in Washington, Missouri. The event was a river cleanup and festival that brought together many volunteers and citizens interested in learning about the Missouri River.

CERC Biologist Patrick Kroboth teaches fourth graders about invasive carps

CERC Biologist Patrick Kroboth teaches fourth graders about invasive carps at the Missouri River Days event hosted by Missouri River Relief. 

(Credit: Aaron DeLonay. Public domain.)

 

 

 

 

 

 

 

 

 

 

 

On April 22nd, the semi-annual Missouri River Days event brought out some 4th graders from Columbia Public Schools and the CSRP scientists were on hand once again to run the “Meet a Fisheries Biologist” station. Scientists got to share their science and experiences with children who often don’t get much exposure to the Missouri River and its ecosystems.

To learn more about Missouri River Relief, you can check out our recent post where they honored us as 2018 Partners of the Year.

 

 

 

 

 

 

 

 

 

 

Developing remote sensing methods for tracer studies in rivers

By Susannah Erwin, PhD

April 15, 2019

USGS scientists inject dye into a tank containing turbid water intended to mimic conditions encountered on the Missouri River.

USGS scientists inject dye into a tank containing turbid water intended to mimic conditions encountered on the Missouri River.

(Public domain.)

CERC scientists are collaborating with researchers from Missouri University of Science and Technology (Rolla, MO) and the USGS Geomorphology and Sediment Transport Laboratory in Golden, CO, part of the Water Mission Area’s Integrated Modeling and Prediction Division, to develop and test new remote sensing methods for mapping flow patterns in rivers. Tracer studies that make use of a harmless but highly visible fluorescent dye can provide insight on how the flow redistributes organisms and other materials via a process called dispersion [for more information on dye studies, see our 2016 experiment]. Typically, these studies involve deploying instruments to measure dye concentration over time at discrete locations. However, pilot studies have demonstrated that passive optical remote sensing techniques could be used to produce image-derived maps of dye concentrations that provide much more extensive and detailed spatial information on dispersion patterns. These methods, developed by USGS scientist Dr. Carl Legleiter, could become a powerful tool for evaluating the performance of channel-reconfiguration projects – for example, Interception and Rearing Complexes (IRCs) for age-0 pallid sturgeon – by allowing scientists to better characterize processes such as mixing and retention.   

A drone operator from Missouri S&T prepares for takeoff

A drone operator from Missouri S&T prepares for takeoff during hydrologic studies at the Columbia Environmental Research Center.

(Public domain.)

In April 2019, USGS scientists and colleagues from Missouri University of Science and Technology conducted experimental trials at CERC to evaluate how turbidity affects remote detection of dye from hyperspectral image data. Different combinations of dye and fine sediment were mixed in tanks and both hyperspectral images and more typical color photos were acquired using a pair of small unmanned aircraft systems (UAS). Scientists are currently evaluating the data, but the initial results from this study are encouraging, indicating the potential to incorporate a remote sensing approach into a dye tracer study planned for the Lower Missouri River at a later date in 2019.

 

 

Ready or Not–Spring is Here

March 29, 2019

Springtime is upon us here at the Columbia Environmental Research Center. With the return of sunshine and warmer temperatures comes the excitement associated with preparations for the field and laboratory season.  Preparations for laboratory studies began this week by evaluating the reproductive condition of captive pallid sturgeon broodstock maintained in the outdoor, pallid sturgeon broodstock facility.  These hatchery-origin broodstock provide the eggs, free embryos, and larvae needed for laboratory studies to improve the understanding of these early life stages. 

CERC biologists seine a broodstock pallid sturgeon holding facility

CERC biologists seine a broodstock pallid sturgeon holding facility during recapture efforts at the Columbia Environmental Research Center. The water levels were dropped to facilitate total recovery of the maintained population.

(Public domain.)

Since pallid sturgeon have a multi-year reproductive cycle, the broodstock maintained at the Center must be evaluated each spring to determine if they will spawn in the coming season.  The outdoor broodstock facility is drained over two days and the adult pallid sturgeon are seined with a net and placed in recirculating holding tanks.   Each sturgeon has a small implanted PIT (Passive Integrated Transponder) tag with a unique number that biologists can detect and read to track its individual history in a computer database.  Biologists check each sturgeon’s PIT tag and perform a general wellness check, and record its length and weight.  A non-invasive ultrasound is then used to assess the sex and reproductive condition of each sturgeon.  Pallid sturgeon found to be near reproduction are transferred to holding systems and closely monitored as spring progresses.  Sturgeon not ready this spring are returned to the broodstock facility to await next year.

A CSRP biologist recovers a broodstock pallid sturgeon from a seine net

A CSRP biologist recovers a broodstock pallid sturgeon from a seine net during recapture efforts at the Columbia Environmental Research Center. 

(Public domain.)

Information gained from laboratory studies on reproduction and the early life of pallid sturgeon would not be possible without captive adult pallid sturgeon populations at this Center, at the U.S. Fish Wildlife Service National Fish Hatchery in Gavins Point, and the Bozeman Fish Technology Center.  These studies provide invaluable insights into the details of sturgeon reproduction and early life stages that are impossible to monitor in their natural habitats.

CERC biologists record biological data of broodstock pallid sturgeon

CERC biologists record biological data of broodstock pallid sturgeon following recapture from the holding facilities. Each fish was checked for PIT tags, length, weight, and given a reproductive assessment. 

(Public domain.)

 

Mapping the river with lasers

By Brian Anderson and Susannah Erwin

March 21, 2019

 

LiDAR point cloud

LiDAR point cloud showing riparian vegetation and the river bank along the Upper Missouri River.  Elevations are in meters above sea level and increase from blue (river bank) to yellow and red (tops of trees).

(Public domain.)

USGS scientists are using laser technology to collect topographic data along the Upper Missouri River.  The laser, a lightweight and portable LiDAR (Light Detection And Ranging) system, is approximately the size of a hockey puck and transmits up to 300,000 laser pulses per second.  A sensor on the instrument precisely measures the time it takes each pulse of the laser light to be reflected back from the surrounding river bank and vegetation.  Using the speed of light (186,000 miles per second or 0.3 meters per nanosecond) and precise Global Navigation Satellite System (GNSS) positions the the LiDAR system calculates the distance and elevation of every reflective surface in the surrounding area.  These reflected pulses from the laser are processed into a point cloud (fig. 1), which provides a three-dimensional topographic map of river banks, bars, and vegetation.  The topographic data from LiDAR complements bathymetric data collected by survey boats, allowing scientists to generate detailed digital models of the entire river channel.  These data are then used to develop flow and particle tracking models to simulate downstream dispersal of pallid sturgeon free embryos. 

 

In September 2018, CERC scientists travelled to Glasgow Montana to collect LiDAR data along a 20+ kilometer section of the Upper Missouri River.  The LiDAR system was mounted in a jon boat (fig. 2) and each river bank was scanned.  Each pass was collected in a single day.  By comparison, a standard survey with handheld GNSS equipment would have taken several days to complete and collected only a small percentage of data acquired using the LiDAR system.

 

Research Hydrologist Susannah Erwin prepares to collect LiDAR data

Research Hydrologist Susannah Erwin prepares to collect LiDAR data on the Upper Missouri River.  Inset:  The Velodyne LiDAR Puck LITE unit, left, with GNSS antenna, right.

(Public domain.)

 

Missouri River Natural Resources Committee, Pierre, SD

March 3, 2019

Columbia Environmental Research Center Hydrologic Technician presents research at the Missouri River Natural Resources Committee

Columbia Environmental Research Center Hydrologic Technician presents research at the 2019 Missouri River Natural Resources Committee's meeting in Pierre, SD

(Public domain.)

A contingent of scientists from the Columbia Environmental Research Center’s River Studies Branch will be taking their science to the 2019 MRNRC Missouri River conference from March 5-7. The event is attended by State and Federal Agency scientists and managers, members of academia, and concerned parties throughout the Missouri River basin. CERC science will consist of posters and presentations on the following topics:

 

Presentations:

Laboratory experiments to evaluate hydraulic factors mediating dispersal of pallid sturgeon by Maura Roberts

Hydrodynamic modeling and particle tracking to inform understanding of pallid sturgeon dispersal in the Upper Missouri River, MT by Bruce Call

Effects of temperature on the development of pallid sturgeon free embryos reared in the laboratory by Kim Chojnacki

Long-term Catch Rate Trends for Sturgeon Chubs and Sicklefin Chubs in the Upper Missouri River by Patrick Braaten

Posters

Improved characterization of age-0 sturgeon interception from hydraulic measurements, Lower Missouri River by Ed Bulliner, Bruce Call, and Carrie Elliott

Reconnaissance Survey of Spawning Habitat Potential in the Lower Yellowstone River, Montana by Carrie Elliott, Robert Jacobson, and Ed Bulliner

The first examination of diet items consumed by wild-caught black carp (Mylopharyngodonpiceus) in the U.S. by Barry Poulton, Patrick Kroboth, Jennifer Bailey, Amy George, Steve McMurray, Scott Faiman, and Duane Chapman

 

 

It takes a village

Dr. Barry Poulton, an Ecologist at the USGS describing the importance of the macroinvertebrate community

Dr. Barry Poulton, an Ecologist at the USGS, Columbia Environment Research Center, describing the importance of the macroinvertebrate community of the Missouri River at a Big Muddy Speaker Series event sponsored by Missouri River Relief in October 2018.

(Credit: Aaron DeLonay. Public domain.)

January 29, 2019

While our schedules here at the Comprehensive Sturgeon Research Project are often busy and a bit hectic, sometimes the opportunity presents itself for our scientists to share their knowledge and experiences with the community.  When Missouri River Relief, a local not-for-profit organization dedicated to Missouri River stewardship, offers such opportunities, we really try to accommodate as we know an attentive, appreciative audience and a worthwhile cause await us.  While getting to share our work is its own reward, we were humbled and immensely grateful when Missouri River Relief named us their 2018 Partners of the Year.

The award reads:

“Partnerships are key to building an organization that reaches and includes a wide variety of individuals and organizations. When partners jump on board, they bring all of their strengths and resources. If you look at all the projects that Missouri River Relief does each year, none of those would be possible without the dedication, generosity and shared passion of our partners. Our Annual "Partner of the Year Award" honors those partners that share our mission and selflessly give of themselves to make our projects a success.

In the many years this recipient has been a partner, they have shared their expertise and knowledge with Missouri River Relief as presenters, education program instructors, and consultants.

They have contributed greatly as presenters at the Big Muddy Speaker Series, always drawing a large audience with invigorating topics such as "Probing the depths of the Big Muddy: What does the bed of the Missouri River look like?"

They have provided students with an up-close look at their research as instructors during Missouri River All Stars After-School Program and Missouri River Days, a program that takes out the entire 4th grade.

They have provided guidance and support in the development of our Missouri River Information packets, which has been downloaded 1,200 times.

We could not be more grateful for this partnership, they have served as a "compass" to guide us in furthering our knowledge of the Missouri River through their research efforts.”

Carrie Elliott, a hydrologist at the USGS, Columbia Environment Research Center teaches fourth grade elementary school children

Carrie Elliott, a hydrologist at the USGS, Columbia Environment Research Center teaches fourth grade elementary school children during Missouri River Days about how scientists use hydroacoustic technology onboard USGS research vessels to map the Missouri River and measure habitats where fishes live.

(Public domain.)

We here at the CSRP would like to thank Missouri River Relief for this great honor and send congratulations to Robert Jacobson, Ph.D., Carrie Elliott, Duane Chapman, Aaron DeLonay, Sabrina Davenport, Dave Combs, and all those working behind the scenes for their work in spreading science and helping preserve the Big Muddy.  

 

 

To revisit what happened in 2018 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!