B08_Attachment 16 - Combined_AMW 2024_Documents_Summary and Slides.pdf

Final August 21, 2024

MRRIC 2024 AM Workshop Summary - FINAL Page 1 of 16

Missouri River Recovery Implementation Committee (MRRIC) 2024 Adaptive Management (AM) Workshop

Wednesday, July 31 – Thursday, August 1, 2024

Workshop Summary

I. Action Items

Action Item Who To be Completed by

1. Post presentation slides and workshop recordings on APAN and Dropbox

RESOLVE COMPLETED

2. Share product capturing ISAP feedback from D&F

TPSN, ISAP Thurs., August 15

3. Share final Adaptive Management Compliance Report

USACE Fri., August 30

II. Objectives and Materials

On Wednesday, July 31 and Thursday, August 1, 2024, the Fish and HC Work Groups, Technical Teams, and Independent Science Advisory Panel (ISAP) gathered for the AM Workshop to: 1) explore management options building on the draft 2023 Adaptive Management Compliance Report (AMCR), lessons learned from AM implementation, and insights gained from writing the Biological Assessment; 2) define priority information to support future decision-making; and 3) discuss tradeoffs and priorities for implementation and strategic direction given current budget context.

Recordings of the workshop are available at the following link:

https://www.dropbox.com/scl/fo/sa02zvywh61kynl97epio/ALqtzxE1nUHSzdj4bUcgZkc?rlkey=hpihmr tc31mmi1qdys7cf3jtw&st=8ce3isp5&dl=0

Materials related to the meeting, including slides presented, can be found on APAN and Dropbox.

III. Key Points from Presentations and Discussions

Opening Remarks – Day 1 Greg Totzke and Paul Lepisto, Fish Work Group Co-POCs, opened the meeting by thanking organizers and participants in the pre-meeting sessions, including the Discuss and Feedback (D&F) session with the Independent Science Advisory Panel (ISAP) and the Bank Stabilization and Navigation Project (BSNP) Mitigation Program Field Trip.

Joe Bonneau, US Army Corps of Engineers (USACE), welcomed attendees to the meeting and introduced key topics for discussion, including the draft Biological Assessment, results from the Fort Peck Test Flow, and upcoming revisions to the 2018 Science and Adaptive Management Plan (SAMP), among other topics.

https://community.apan.org/wg/mrric/m/mrric---2024?folderId=73a027c6-8118-ef11-82f7-066267aa8e72&parentId=1281ea15-7618-ef11-82f7-066267aa8e72&GalleryPostSort=Subject&SortOrder=Ascending https://www.dropbox.com/work/Maya%20Breitburg-Smith/MRRIC/Shared%20Folders/2024%20AM%20Workshop https://www.dropbox.com/scl/fo/sa02zvywh61kynl97epio/ALqtzxE1nUHSzdj4bUcgZkc?rlkey=hpihmrtc31mmi1qdys7cf3jtw&st=8ce3isp5&dl=0 https://www.dropbox.com/scl/fo/sa02zvywh61kynl97epio/ALqtzxE1nUHSzdj4bUcgZkc?rlkey=hpihmrtc31mmi1qdys7cf3jtw&st=8ce3isp5&dl=0 https://community.apan.org/wg/mrric/m/mrric---2024?folderId=73a027c6-8118-ef11-82f7-066267aa8e72&parentId=1281ea15-7618-ef11-82f7-066267aa8e72&GalleryPostSort=Subject&SortOrder=Ascending https://www.dropbox.com/scl/fo/oi3w2uwsdh3k70ihy8299/AFchZuPc8tuVdOeegKzHDaM?rlkey=nyp9owem2laar8plgmv71rq62&dl=0

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Context Setting: Lessons Learned from AM Implementation The slide presented in this session is available on APAN and Dropbox [2024 AM Workshop v2.pdf, slide 3].

Presentation Dr. Bonneau shared lessons learned from adaptive management (AM) implementation thus far, including:

1. Discussions with stakeholders are most useful if they are focused on specific topics, and productive engagement requires a high level of effort from USACE and stakeholders.

2. It is important for USACE to be clear about what aspects of the MRRP are true adaptive management, and what is not.

3. Different people can draw different reasonable conclusions from the same information based on where they place value and risk. Successful consensus building requires in depth discussions about these risks and values.

4. Independent review, from the ISAP and other parties, is critical for MRRP managers to have an external perspective on the program.

5. Scientists need time to engage solely with each other, beyond just the AM Workshop or Fall Science Meeting.

6. While it is difficult to manage the MRRP with so much variation in funding levels, it is beneficial in that the program’s priorities must always be clear.

Discussion An ISAP member commended Mr. Bonneau on his team’s stakeholder engagements related to the Fort Peck Test Flow. He also affirmed that consultation is part of AM and should not be considered separate from that process. He encouraged USACE to add consultation to their AM framework, including in future AMCRs.

Wayne Nelson-Stastny, USFWS, contrasted USACE’s approach to engagement around Fort Peck Test Flows to the approach undertaken for the Interception and Rearing Complex (IRC) management action, saying that some stakeholders were unaware of the IRC action when it came time to build the first two IRCs. Gail Bingham, MRRIC, concurred and noted that while there was a much deeper level of engagement when the sites for the third and fourth IRC were selected, it had come too late in the process. Dr. Bonneau agreed that USACE had learned from that experience to start with in-depth engagement rather than wait for problems to arise.

Introduction of Biological Assessment The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 4-26; 2024 AM Workshop_NelsonStastny.pdf].

Presentation Dr. Bonneau provided background on the process through which USACE and USFWS arrived at the current re-consultation on the Biological Assessment. The 2000-2003 jeopardy opinion on the Pallid Sturgeon from USFWS encouraged USACE to embrace AM, and required management actions such as spring pulses, shallow water habitat, and propagation. In 2011, ISAP evaluated USACE’s approach to the spring pulse and AM and issued a report highlighting the need to explain the mechanistic relationship between management actions and pallid sturgeon response, among other recommendations. USACE conducted an effects analysis and out of that developed the Science and Adaptive Management Plan (SAMP). In 2017 USACE submitted the SAMP to USFWS along with a variety of proposed actions, https://community.apan.org/wg/mrric/m/mrric---2024?folderId=4038706e-4a4f-ef11-82fd-066267aa8e72 https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0 https://community.apan.org/wg/mrric/m/mrric---2024?folderId=4038706e-4a4f-ef11-82fd-066267aa8e72 https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

MRRIC 2024 AM Workshop Summary - FINAL Page 3 of 16 including IRCs and natural flow evaluation. Dr. Bonneau briefly reviewed issues with the IRC management action, which USACE was not able to fully implement, as well as the status of other ongoing actions.

Dr. Bonneau then shared a few reasons that AM efforts for pallid sturgeon have not yet been successful.

These included:

• Links between environmental factors and pallid reproduction and recruitment have not been established, making it difficult to design actions that will support these outcomes.

• The fundamental understanding of the species necessary to conduct AM does not yet exist, and that lack of information also means USACE is unable to model scenarios and test alternative effects.

• USACE’s monitoring scheme is not capable of tracking recruitment, its fundamental objective.

• Support for the program has been challenging to maintain due to all of these factors.

He then shared a few details about what is proposed in the draft 2024 Biological Assessment (BA). The changes focus on pallid sturgeon actions in the lower river. USACE plans to continue evaluating natural flows and contributing to the stocking program, and to continue population monitoring science efforts with a refined focus on measuring survival to age-1. The IRC management action and spawning habitat management action are not part of the new BA.

Todd Gemeinhardt, USACE, discussed the draft BA’s draft science and monitoring priorities. The draft BA seeks to address existing data gaps in order to be able to assess recruitment. Age-0 sampling will continue and will be used to assess parental contribution as well as annual reproduction. USACE will also evaluate age-0 habitat usage. Significant effort will go into establishing a recruitment index for age-1 sturgeon, including improving biologists’ ability to catch these fish. USACE also hopes to assess recruitment to ages 2 and 3, but the fish are challenging to age at that size. In addition, the BA includes plans to understand transport to the Mississippi River; evaluate the factors influencing adult condition and reproductive status; conduct an assessment of the effect of similarity of appearance on pallids’ current status; estimate population abundance; and develop models to simulate effects of management actions.

Mr. Nelson-Stastny shared USFWS’ perspective on the current situation with the BA. He emphasized that the Endangered Species Act (ESA) instructs his agency to use the “best available science” to make decisions and recover species. He noted that while little was known about pallid sturgeon at the time, the 2000-2003 Biological Opinion was based on ecological principles and existing knowledge about big river fishes, the ecology of the Missouri River, and the changes to it due to the operations and maintenance of the BSNP and the Dams. He questioned whether it was possible to understand pallid sturgeon habitat requirements in a highly modified system that provides very little of the habitat they evolved with and raised similar questions around evaluating “natural” flow variation. Mr. Nelson Stastny encouraged MRRIC to focus on the effects of federal actions on the river and its species.

Discussion An ISAP member noted that even age-1 shovelnose sturgeon are challenging to capture, and asked whether there was another age or size that could be indexed that might be easier for USACE to consistently catch. Dr. Bonneau said it was possible his team would learn that they could understand recruitment by catching younger fish, but that’s often not the case with fish species. The ISAP member suggested assessing older fish to evaluate recruitment. Dr. Bonneau said that to assess recruitment it is

MRRIC 2024 AM Workshop Summary - FINAL Page 4 of 16 essential to know the age of a fish, and while it is possible to accurately age an age-1 or age-2 pallid, it is challenging to age pallids once they are more than 5 years old.

A MRRIC member asked whether USACE had assessed the potential influence of runoff from urban areas and agriculture on spawning and recruitment. Dr. Bonneau responded that pallid sturgeon sampling occurs throughout the river, including near cities and farms, and water quality monitoring was ongoing outside of the MRRP. He noted that experts have said there are many potential impacts from contaminants on pallids, but no clear link has been established.

Discussion of Biological Assessment: Key Topics and Implications The questions discussed during this session in slides available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 27-29; 2024 AM Workshop_NelsonStastny.pdf, slides 6-7].

Discussion A MRRIC member asked about the stability of the wild pallid sturgeon population. Dr. Bonneau responded that in the upper basin, no recruitment has been observed and the wild population is in a steady decline. In the lower basin, catch rates have been steady since monitoring began, implying that recruitment is occurring. However, without evidence of how much recruitment there is or how often it occurs, USACE cannot say whether the population is increasing or decreasing.

Members asked about the distinction between ESA requirements and BSNP mitigation requirements, proposing that there may be opportunities for synergy between the two. Mr. Nelson-Stastny agreed, suggesting that land acquisition and establishment of fish and wildlife habitat under the BSNP Mitigation Program could benefit pallid science efforts. Dr. Bonneau noted that while the two are related, BSNP mitigation requirements are unaffected by pallid recovery metrics and not all of the mitigation habitat would benefit pallids.

In response to member questions about the status of science around IRCs, Mr. Bonneau said that USACE would continue to monitor the four existing IRCs, but less would be learned from 4 than the planned 12.

He also noted that while it was hypothesized that IRCs would both intercept pallids and provide food and forage, evidence suggests that pallids are not food-limited. Greater scientific uncertainty remains around interception and broader drift dynamics.

A MRRIC tribal member offered his perspective. For his tribe, the Missouri River is an integral part of history and culture. Its water is sacred, and the natural ecology of the river provides medicinal foods and is integral to ceremonial aspects of their culture. He appreciated the scientists in the room for highlighting the impact of manmade dams on that natural ecology, noting that tribes as well as wildlife have been affected by these changes. Finally, he expressed his support for long-term funding for the pallid sturgeon program to create a future vision for the river’s recovery.

Another member noted that the new BA seemed to be moving away from actions to restore habitat on the river, which was ultimately what pallids and other fish need to survive. He said that pallids seem to be surviving better on the upper river, where the river’s form and flow is more natural, and that changes in historical habitat and flows seemed to have clear negative effects on sturgeon.

A member observed that the IRC management action seemed to suffer from the absence of a “plan b” if it could not be implemented, and asked if the new proposed approach incorporated more alternatives in order to avoid the present situation. Dr. Bonneau responded that there were many alternative plans to https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

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IRCs, but they all suffered from the same shortcomings as the IRC management action – namely, lack of support. Addressing that broader issue and gathering evidence to support future actions is the new “plan a.”

In response to a question about how USACE planned to develop a chain of causality between environmental factors and pallid year class, Dr. Bonneau noted it would take time to gather data on environmental conditions in enough years to establish causal relationships and would require USACE to detect recruitment and when and where it occurs.

In response to a member question on the impacts of the BSNP on the Missouri River, Mr. Nelson-Stastny referred her to the 1980 Fish and Wildlife Coordination Act report, which outlines many of those impacts.

An ISAP member questioned whether BSNP mitigation lands were intended as a resource during isolated extreme flooding events or would play a larger role in rewilding parts of the river system, noting that the latter would likely impact the navigation channel. Dr. Bonneau responded that the intention was more to create connectivity during large scale flooding events, and stakeholders had recommended focusing on properties between levees and the river that are connected by variable flows, and potentially contributing to levee setbacks. Mr. Nelson-Stastny said that it was possible that different methods could be employed to maintain the BSNP that would produce habitat as well as a navigation channel.

In closing, Mr. Nelson-Stastny challenged the group to consider “no-regrets” actions that could be taken now to set up the MRRP for success in the future once the science was clearer.

Dr. Bonneau said this was the start of technical discussions on the draft BA that he hoped would continue beyond the AM Workshop, saying he would like to schedule further engagements with the ISAP that were currently not funded in the MRRP budget.

Status and Trends: Population Monitoring and Modeling – Lower and Upper Basins The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 30-39].

Presentation Dave Marmorek, ESSA reviewed the pallid program’s objectives, which are to avoid jeopardy by increasing pallid sturgeon recruitment to age-1, and by maintaining pallid numbers using propagation until sufficient natural reproduction occurs. Preliminary estimates for 2023 show that there were 39 wild-origin and 334 hatchery-origin adults in the Upper River, and 760 wild-origin and 2283 hatchery-origin adults in the Lower River. These numbers are likely underestimates because they assume no natural recruitment. Numbers of wild adult fish are gradually diminishing, while hatchery fish are moving into the adult stage and will hopefully begin to reproduce. Hybridization is a concern on the lower river, with about half as many hybrid adults as wild pallid adults. The Fish Tech Team continues to work to develop an index of year class strength based on capture-recapture dates of wild and unknown origin sturgeon.

Discussion In response to a question from an ISAP member, Mike Colvin, USGS, explained that the estimate of the hybrid population is based on a sample of fish that appeared to be pallids but were revealed to be hybrids by genetic testing. Another ISAP member asked whether USACE had considered taking a genetic https://www.dropbox.com/scl/fi/z71me87lzu8fgr1icywka/1980-BSNP-FWCA-Report.pdf?rlkey=40y4772lbgvt9627khmgr28bi&st=4wgf9x6w&dl=0 https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

MRRIC 2024 AM Workshop Summary - FINAL Page 6 of 16 subsample of all sturgeon caught by the fish team, rather than just those that phenotypically appear to be pallids. This would allow them to monitor the encroachment of hybrids. Dr. Colvin responded that it was possible but would have to be included in cost benefit analyses used to make decisions about which science activities most improved the state of knowledge on pallids. The ISAP member noted that hybridization could be creating issues for the species, if hybrids are reproducing and outcompeting pallids.

A MRRIC member asked the tech team what was currently known about hybrids. Aaron DeLonay, USGS, responded that they are reproductively viable, as are their offspring, and will spawn with pure pallids and pure shovelnose. It is not clear whether they are more or less reproductively viable than pallids.

A tech team member asked whether hatchery individuals counted towards recovery objectives. Mr.

Nelson Stastny responded that only naturally produced fish were counted, meaning that hatchery-origin fish don’t count but their offspring do.

An ISAP member questioned why USACE was focused on an index of year class strength rather than demographic rates. Dr. Bonneau replied that it was more achievable to get at relative strength than specific numbers. Pallids also have an elaborate life cycle that is not well understood. Reproductive readiness in a given year is an aspect of their life cycle that USACE feels more confident it can evaluate.

Management Action: Evaluation of Lower River Flows at Gavins Point The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 40-52].

Presentation Ibrahim Alameddine, ESSA, provided an overview of the fish tech team’s work on evaluating natural flows out of Gavin’s Point dam to assess the evidence for implementing spring pulses. USACE must make a decision whether or not to implement a spring pulse in 2027, so the tech team has begun an exploratory analysis of existing data on how different aspects of flow influence pallid aggregation, spawning, and recruitment. This includes historical data from before this evaluation began, going back to 2007. This analysis showed that spawning date and migration velocities were weakly correlated with flows. However, flow is a difficult variable to assess and the tech team is continuing to refine what metric of flow is most useful. The analysis also showed that spawning occurred prior to the late spring flow peak in all years assessed, meaning early season flows are more relevant to management. Rates of upstream migration and spawning dates were also correlated with temperature thresholds and cumulative thermal units. He also discussed the location of spawning events, which show a wide variation but are somewhat clustered in the upper portion of the lower river.

Discussion Mr. DeLonay noted that there are caveats to looking back at historical data, since it was rare to catch adult fish then and they were tagged for telemetry opportunistically rather than systematically. Thus, the telemetry dataset from the years before the new SAMP is not ideal.

An ISAP member asked how confidently the Fish Tech Team could identify when a fish spawned, and also what degree of fidelity pallids exhibit to specific spawning sites. Mr. DeLonay responded that fish are tracked with various levels of intensity. For the most intensely tracked fish, the tech team is able to observe patterns of motion in the river that indicate spawning, and then the team recaptures them to confirm they have released their eggs. There is less certainty regarding spawning in other fish. Mr.

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DeLonay also noted that now that more fish are tagged, the team has observed that fish spawning repeatedly at specific locations. Anecdotally, they are highly aware of environmental contexts, for example swimming long distances away only to return to the same dike they had been in before.

A member asked how many pallid parents contributed to the large number of age-0 fish caught in 2021, and how that correlated with telemetered spawning data. Dr. Bonneau responded that his team had observed only one female spawning, but genetic analysis of that year’s age-0 catch showed that it took 54 adults to produce them. As such, determining the number of contributing adults via age-0 samples is a high priority for future years.

A member asked how the tech team could apply what it learned from the Fort Peck Test Flows to the lower river. Dr. Alameddine replied that they had learned a lot that could be carried over, but there were important differences that needed to be accounted for. Upstream migration is very important in the upper river because of the risk of embryos ending up in Lake Sakakawea, while in the lower river an upstream spawning location is less critical for survival. However, if fish in upper river are found to respond to high flows, it would suggest fish in the lower river would do the same.

A member asked how this data might affect future releases from Gavin’s Point, expressing concern about the effects of increased flows and higher temperatures on hydropower generation. Dr. Alameddine noted that, while a strong correlation between flows and pallid behavior had not yet been established, it was not out of the question that evidence could emerge in support of increased spring flows. Dr.

Bonneau added that USACE does not have the ability to control the temperature of releases from Gavin’s Point Dam.

In response to a question about the quality of available spawning habitat, Dr. Bonneau said that the tech team is working on gathering the data necessary to assess habitat quality. Robb Jacobson, University of Missouri, added that many of the sites where spawning repeatedly occurs are in outside bends that were created by USACE. This fact is the source of continued interest in the spawning habitat hypothesis.

Another member asked what could be learned about pallid spawning habitat preferences based on the current data, which seems to show spawning sites clustered on the upper stretch of the lower river where more habitat restoration has occurred. Mr. DeLonay responded that because the data came from a biased sample of opportunistically tagged sturgeon, and because the fish are responding to a highly altered contemporary system, the results should be interpreted as an example of what pallids can do, not what they prefer to do.

Dr. Jacobson asked about the status of turbidity as an explanatory variable for aggregation, spawning, and recruitment, and inquired whether the tech team had used multivariate modeling to identify the relevant variables from a hydrograph. Dr. Alameddine said his team had not investigated turbidity, mostly because the ability to measure turbidity is limited. He also said they had tried to look at interactions between temperature and flow using multivariate analysis but had not exhausted all possible metrics that can be extracted from a hydrograph. In response Dr. Jacobson suggested that results from Fort Peck on pallid response to turbidity could be applied to the lower river.

In response to a member question Dr. Alameddine explained that the data analysis thus far does not differentiate between wild and hatchery origin fish, but that information is available in the database.

Hybrids are not part of the database of telemetered fish in the study.

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In response to a question about the role of tributaries in this data analysis, Dr. Alameddine noted that while the spawning that is occurring in the Platte River is not incorporated into the analysis, the network of gaging stations does detect the effect of tributary flows on conditions in the river.

In closing, Mr. DeLonay impressed upon attendees just how complex a process the team was trying to model and predict, saying that a large number of factors contribute to migration, aggregation, and spawning, from flows to temperature and the condition of the river bottom, all of which vary depending on where fish are in the river system.

Management Action: Propagation and Augmentation in Lower and Upper Basins The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 53-58].

Presentation Mr. Nelson-Stastny reviewed the history of the propagation program in the upper basin, which has transitioned over time from stocking large numbers of fish to stocking smaller numbers of fish that preserve the population’s genetic diversity. He shared that the program’s ability to estimate population abundance and population sustainability is improving, and the population is becoming more resilient due to the Intake Bypass’s expansion of pallids’ range. However, the effective population size remains low at approximately 10% of recovery plan targets. The propagation program is supporting research initiatives such as the drift study during the Fort Peck test flow in 2024 and a planned drift study on the Yellowstone and Powder Rivers in 2025.

Discussion An attendee asked about the effects of running major larval drift studies in the upper basin multiple years in a row, including the potential for overstocking. Mr. Nelson-Stastny replied that genetic diversity and the river’s carrying capacity were both limiting factors on stocking. Particularly if larvae survive in the river, there is risk in overstocking from the limited number of captive broodstock family lots. And, while the Yellowstone has a significant amount of productive habitat, carrying capacity from Fort Peck to Lake Sakakawea is currently very limited. Pat Braaten, USGS, added that chubs and other fish species that adult pallid sturgeon feed upon are in decline. Initial stocking efforts raised concerns about carrying capacity because growth trajectories diminished considerably between 5 and 6 years of age, likely because they did not have the resources to make the transition from a bug diet to a fish diet. Because of these observed limitations, the tech team concluded that stocking alone was not a viable pathway to species recovery and transitioned to its current approach of preserving genetic diversity.

In response to a question about identifying hatchery origin fish in the future after so many drift studies have been conducted, Mr. Nelson-Stastny explained that USFWS geneticists work to produce genetic crosses that could not be replicated in the wild, in order to make identification possible.

A member asked if the additional drift studies would confound the experiment being conducted at Fort Peck. Dr. Bonneau responded that the goal of the Fort Peck drift study was to understand what conditions allow embryos to settle out before reaching Lake Sakakawea, and the other studies would simply add to the set of conditions in which that can be tested.

Members asked about the relationship between stocking and hybridization, and the historic or natural rate of hybridization. Mr. Nelson-Stastny responded that all broodfish are tested to ensure that they are pure pallids, and the tech team hasn’t investigated potential impacts of stocking upon hybridization.

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There are various theories about historical hybridization rates. Some speculate that it is occurring naturally, following the connection between pallids’ and shovelnoses’ historic ranges post-glaciation.

Others posit that it is caused by changes or limitations in habitat, which is supported by observations that hybridization occurs less frequently in the upper basin where there is enough habitat that the two species can separate from each other.

Another member asked whether the hatchery could support an age-1 seeding event, and whether age-1 fish could be tagged and tracked. Mr. Nelson-Stastny responded that more family lots would be needed in order to add a large number of age-1 fish to the system, because of their high survival rates compared to age-0 fish. Mr. DeLonay added that individuals could be marked 10 days post hatch and beyond through a variety of techniques such as pit tag trawls, but there were severe limitations on telemetry tagging due to the body cavity size and thinness of abdominal walls of young fish.

Day Two: Revisit Biological Assessment Discussion

Presentation Dr. Bonneau opened the discussion by noting that the tech team is working to develop a rigorous plan of action, and said he hoped to put a process in place to get additional technical input from external experts.

Mr. Nelson-Stastny said the current draft BA has a lot of emphasis on understanding pallid population dynamics, and he hoped to see more detail on the environmental factors under evaluation and their connection to the impacts of the federal action.

Austin McCullough, USFWS, shared questions that he had previously posed to USACE, hoping that attendees would take the opportunity to discuss them. These questions included:

• When USACE presented its plan for the BA and related science activities, the team said that once it understood fundamental information, it would lead to actions. What is that pathway and how does USACE envision collecting information to support actions that are within its authority?

• Environmental factors are critical. You mention you’d be looking at flows – what flow metrics are you considering, and how have you considered the interaction between flows and the operation of the BSNP?

In response Dr. Bonneau said it was difficult to plan actions if recruitment and the factors that affect it cannot be detected. However, he indicated he would consider putting an example of how certain information would lead to action in a future draft.

Discussion Dr. Jacobson shared ideas for potential environmental covariates to investigate at low cost, using existing information and models.

• The new Missouri River system model, developed for flood risk reduction, could be used to look at floodplain connectivity and its relationship to migratory events, to evaluate the possibility that connected floodplain acres create more food and forage for pallids. It could also be used to model cueing variables such as flow, temperature, and turbidity.

• Existing 2d hydrodynamic models of river segments could be used to index years based on the energy pallids must expend to move upstream, based on evidence showing fish minimize expenditures in upstream movements by finding threads of low velocity water.

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• Known spawning sites could be investigated and categorized based on their physical variables, as well as which individuals are drawn to each site and the reproductive readiness of these fish.

• The dispersal process could be further investigated using the systemwide model, based on growing understanding from AECs of how wingdikes create channel complexity that slows down drift. Scientists could evaluate how far embryos are drifting downriver from known spawning sites based on each year’s hydrologic conditions.

• The characteristics of age-1 habitat could be investigated in order to learn what supports survival and also improve catchability.

• Scientists could examine potential impediments to returning to the Missouri from the Mississippi that could explain the recruitment occurring there, including Chain of Rocks which seem to create challenging conditions for fish passage upstream at low flows.

Dr. Bonneau asked whether there were other initiatives Dr. Jacobson had considered but did not mention because of cost. Dr. Jacobson said he thought a systemwide 2d hydrodynamic model would be very useful for understanding a variety of environmental factors and does not currently exist.

A member asked whether the ESA Section 7(a(1)) conservation plan incorporated into the last Biological Assessment would have to be evaluated and re-written as part of the current process. Mr. Nelson- Stastny noted there was a difference of opinion between USACE and USFWS about whether the section 7(a(1)) conservation plan was part of the proposed action in the last Biological Assessment. That disagreement does not affect the current BA.

In response to a question about the availability of Areas of Enhanced Capture (AECs) on the river, Kim Chojnaki, USGS said that those channel margin habitats were small in terms of proportion of space in the river but do occur in most bends, depending on water surface elevation.

An ISAP member made the point that in many fish species, juvenile rearing habitat is different from that of adults, and often involves a lot of cover from predation. She encouraged further investigation and argued that investigation could not take place on the lower river, as the system is so highly modified that rearing habitat likely does not exist there. Mr. Nelson-Stastny concurred, saying he had heard from crews in the Mississippi river that they consistently find young sturgeon among willows at the edges of islands.

The ISAP member suggested releasing tagged juveniles in the upper river and identifying what habitats they utilize, then see if you can find any juveniles in existing habitat analogues in the lower river.

Another ISAP member inquired whether field crews observed any change in catch rates over time in the field season, as fish mature and potentially transition habitats. Field crew members said that as fish grow to 100 mm, they appear to choose to go to deeper, faster water and can be found near submerged sandbars. They are harder to catch in these locations, but crew members said there may be better chances of catching larger age-0s with different gear.

A different ISAP member asked how closely field crews track covariates for each catch of age-0 fish. Crew members responded that historic areas of high captures are tracked, and for each catch the nearest gauge station, time period, and variability of flow is taken into consideration. Mr. Gemeinhardt added that a limitation on identifying the impact of microvariation in river beds is that trawls can be 75 to 300 meters in length, and there’s few ways to identify where fish are captured within that trawl.

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In response to a member question about opportunities for public comment on the draft BA, Mr. Bonneau said that such a process would only occur if an action was proposed that was outside what was evaluated in the most recent Environmental Impact Statement (EIS).

An ISAP member asked whether there was an epigenetic research program underway to improve USACE’s ability to age pallids. Mr. DeLonay said there was a DNA methylation technique that has been used to age many species based on changes over time related to age. USGS is collaborating with the University of Buffalo to sequence the entire pallid genome, which could be used to develop an aging tool over a few years of research, as well as bring a variety of other benefits to the program’s understanding of the species. More information on the feasibility of these activities will be available in a few months.

Management Action: Flow Management at Fort Peck The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 60-70; Braaten_Nebraska City_Aug 1 2024.pdf].

Presentation Dr. Bonneau shared information about the ongoing test flow at Fort Peck, intended to examine whether a double spring peak could draw pallids upriver to spawn near Fort Peck Dam. The initial peak is intended to attract fish away from the Yellowstone River, and the second peak is intended to induce spawning. Afterwards, decreased flows seek to slow drift to Lake Sakakawea. Warmer water is also released from the dam’s spillway during the flows. USACE conducted extensive stakeholder engagements to identify an implementation pathway that was supportable by stakeholders while also meeting USACE’s pallid goals. Monitoring for HC impacts, including water quality, dam safety, and cultural resource monitoring, is ongoing and results will be available later in the year. Future decisions about test flows will be made based on these results and the results of fish monitoring.

Dr. Braaten discussed fish monitoring results. When flows first increased on April 26, a number of fish migrated upstream in response, and after the flow there were 23-26 pallids in the Fort Peck area, including 5 reproductive females. Two of those fish were wild and three were hatchery origin. Between the two peak flows, USACE ran retention flows, during which there was some decrease in flow and a concurrent decrease in fish, leaving about 20 fish in the system. The two wild females left for the Yellowstone River, where at least one fish spawned. After the second peak, one of the hatchery origin females spawned, one did not, and one is unknown. This was the first verified spawning event on the upper river since 2011.

A drift experiment was also run concurrently with the test flow. 350,000 free embryos were added to the river in order to assess whether their ability to survive the cold water temperatures from the Fort Peck powerhouse in the short term, and to assess their long-term survival based on drift speed. The team is still working through catch data, but about 1,000 free embryos were collected that could include pallids, shovelnose, and paddlefish.

Discussion Members congratulated the team on the successful implementation and confirmed behavioral response to the test flows.

An ISAP member asked what fraction of radio-tagged fish were involved in the movement upstream. Dr.

Braaten responded that between 40 and 45 wild fish are currently tagged. Two wild males were in the https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

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Fort Peck area when the flow began; one left the system, and another remained. Two wild females came up in response to the flow. Male hatchery fish were the main contribution to upstream movement.

A member asked what the approximate water temperature difference was between the Yellowstone and the Missouri at the time spawning occurred, and what that meant for embryo development. Dr. Braaten said it was unknown exactly where those fish spawned and what the exact conditions were, but normally pallid spawning occurs between 18-22 degrees Celsius, and at that time of year water temperatures are often closer to 14 degrees. In response to a question about differences in embryo development based on spawning site, Dr. Braaten said that both temperature and drift distance could have an effect – for example, pallids often spawn at a site below Fairview, but no recruitment has been observed, likely because of the short drift distance.

A member asked whether the stocked embryos Dr. Braaten’s team caught appeared to have developed to an extent that might allow them to survive in Lake Sakakawea. Dr. Braaten said that the embryos had developed distinct black tails, which indicates that they are sturgeon, but had not yet transitioned to the larval stage. Mr. DeLonay added that work is underway to identify the age at which pallids become mobile.

In response to a question about temperatures this spring in the upper Missouri, Dr. Braaten noted that it hasn’t been assessed yet, but anecdotally it did seem like a cold spring despite having a relatively warm winter. Water temperatures over the Fort Peck spillway were relatively cold as was the air temperature in the late spring, which may have contributed to females spawning relatively late in the season.

A member asked whether HC monitoring was being conducted by a Secretary of the Interior qualified archaeologist. Dr. Bonneau confirmed that the HC monitoring crew was composed of Secretary of Interior qualified archaeologists and architects, as well as traditional cultural specialists trained and approved by the Fort Peck tribes.

In response to a member question, Dr. Bonneau noted that efforts around the test flow did not end with the second peak and fish and HC monitoring was continuing.

Mr. McCullough asked why USACE made the decision to decrease retention flows, especially given that data showed that two reproductive females left the system during that time. Dr. Bonneau responded that how decisions are made and drawing conclusions about their effects are two separate questions.

Fish and HC data from the test flow is going to be analyzed by the tech team and brought up for discussion at the next AM Workshop. That will inform plans for the next test flow. An ISAP member asked whether it was possible to consider fish responses in real time during future test flows. Dr.

Bonneau said the team was considering that possibility, since fish monitoring allows for it to some degree. However, USACE’s ability to adjust flows in response to monitoring data is limited because of potential HC impacts.

Management Action: Passage at Intake Dam and Spawning on the Yellowstone River The slides presented in this session are available on APAN and Dropbox [Final Lower Yellowstone Fish Passage Project Update_July 2024.pdf].

Presentation David Trimpe, Bureau of Reclamation, provided an update on fish passage through the bypass channel at Intake Dam thus far in 2024. He reminded the committee that prior to the construction of the bypass https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

MRRIC 2024 AM Workshop Summary - FINAL Page 13 of 16 channel, pallids were confined to the lower 70 miles of the Yellowstone. Now their range has been expanded another 160 miles up the Yellowstone, 220 miles or more up the Powder River, and 120 miles up the Tongue River. This year flows from the Yellowstone were below average overall, and only 14 fish have passed through the bypass channel compared to 22 in 2022 and 26 in 2023. Wild fish who made it up to Intake Dam were quite motivated to pass, with 6 of 7 making it through the channel, while hatchery fish exhibited less motivation, with only 8 of 16 passing. Immature hatchery fish have also been observed swimming upstream as flow decreases which is unusual. The Powder and the Tongue were hotspots for spawning, with 7 fish and 1 fish spawning respectively. There have been challenges with erosion in the channel, which will require a major repair effort this fall and winter.

Discussion An ISAP member asked whether any embryos, larvae or age-1 recruits had been observed in the upper river following all this spawning. Dr. Braaten said that free embryos had been caught but no wild larvae, 1-year olds, or 2-year olds had been caught. The best evidence points toward recruitment failure or curtailed recruitment since the mid-1950s. Lake Sakakawea was dammed in 1952-53 and filled by 1961.

Carbon-14 dating has also shown that all wild fish tested were born before 1957. Lake Sakakawea’s anoxic zone and stagnant water is likely detrimental to recruitment for riverine fish.

An ISAP member commented that he would like to see this information presented in a framework that’s more explicitly tied back to adaptive management.

Updating the Science and Adaptive Management Plan The slides presented in this session are available on APAN and Dropbox [2024 AM Workshop v2.pdf, slides 78-91].

Presentation Marc Nelitz, ESSA, discussed plans for the forthcoming update to the 2018 SAMP. It was developed as a companion document to the EIS USACE prepared in the same timeframe, and was an important reflection of USACE’s commitment to adaptive management for the MRRP. It incorporates discussion of adaptive management governance; science for each species; critical uncertainties affecting management; multilevel applied research and AM actions to reduce these uncertainties; data management; and approaches to HC. A lot has changed since 2018 so these updates will reflect that, including: elaborations on the AM process; strengthening the process of determining state of knowledge and assessing hypotheses; updates to reflect tern delisting and new decision criteria; incorporating guidance emerging from consultations, inputs from MRRIC, and lessons from Fort Peck engagements;

and updates to reflect the current state of data management including the IMS. Updates will proceed following completion of the consultation.

Discussion Mr. Nelitz asked attendees what content and processes of the SAMP they’d found most useful and relevant, and what content and processes could be improved or rethought in the revised SAMP.

A member noted that the sections of the SAMP discussing decision criteria were underdeveloped and could be updated. Mr. Nelitz responded that the team was considering moving away from decision criteria to “evaluation criteria,” as many critical questions are hard to frame as a yes or no, did you meet the criteria sort of way.

https://www.dropbox.com/scl/fo/tz953xvucj5q16glvubhj/AJjAJhC6jrehWyM9w7IIwb8?rlkey=gga4j0vpogp72u6x1lmqpl08v&st=54sfst7m&dl=0

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An ISAP member said chapters 1 and 2, which introduce the SAMP overall and discuss AM Governance, were particularly useful and should be retained.

Another ISAP member said it would be critically important for the revisions to clarify the AM process in Chapter 1 and how it feeds into the science in Chapters 3 and 4. He pushed USACE to be transparent in how science was being used to make decisions.

Ms. Bingham proposed that the SAMP consider more deeply how different players, including stakeholders, could be engaged in the AM process. He also noted that the Tribal Interests and HC Work Groups are charged with considering the Biden Administration’s ITEK policy and there could be opportunity to consider where the overlap between tribal concerns, indigenous knowledge, and the MRRP exists through the SAMP revision process. An ISAP member responded that deep engagement would be necessary to get tribes to the table to discuss ITEK in the context of the SAMP.

A tech team member asked how the hypothesis reserve in the SAMP was brought into the AM process.

Mr. Nelson Stastny responded that part of what caused the reconsultation was that there did not seem to be an alternative hypothesis ready to be acted upon when IRCs could not be implemented. Improved SAMP governance would help with this issue.

Another member asked what MRRIC and the ISAP’s role would be in the SAMP update. He suggested reviewing all existing ISAP recommendations and asking for new input. Dr. Bonneau noted USACE has been tracking needed changes for years based on science panel comments and its own observations and proposed discussing with the panel after drafting whether those needs had been addressed. Ms.

Bingham asked if this could be discussed at the December plenary meeting and Dr. Bonneau said that could work. He suggested addressing that topic in the SAMP revision. Mr. Nelson-Stastny cautioned that it was important to consider what’s the most efficient use of time for both stakeholders and technical team members, and whether MRRIC engagements were the best forum for technical scientific discussions as opposed to HC concerns. Gail Bingham, MRRIC Chair, replied that MRRIC was not only concerned with HC issues, and the ISAP is charged to advise both MRRIC and USACE.

An ISAP member said the ISAP was heavily involved in the production of the original SAMP and should be fundamentally involved in the revision of this document. However, there are virtually no resources for ISAP participation in the September or December plenary meetings. Another ISAP member stated that writing a document then allowing ISAP to review it was not an efficient way to engage them. She expressed her frustration at the lack of opportunities for the ISAP to help the program move forward at venues that are specifically designed for scientists to engage with each other. Communicating science to MRRIC is important but opportunities for scientist-to-scientist discussions are missing from the program.

A MRRIC member noted that the July 30 ISAP D&F seemed to incorporate less discussion than usual, and instead was mostly…