1. Objectives

There are three objectives:

• Understand how temperature and exposure to sublethal levels of total dissolved gas (TDG) influences Snake River fall Chinook subyearling predation risk;
• Quantify spatial and temporal variation of subyearling loss to predation in Lower Granite Reservoir; and
• Evaluate the use of otolith microchemistry to identify natal, rearing, and overwintering areas; and age, timing, and size at ocean entry of juvenile fall Chinook salmon.

The Snake River Fall Chinook project began in 2002 and has addressed a variety of objectives that are important to salmon management. The investigators have published more than 50 journal papers stemming from this effort, indicating that project objectives and hypotheses were specific and clearly defined, measurable, and testable. The narrative summarized how the various objectives were applicable to the Fish and Wildlife Program and management issues. Timelines were provided for some specific efforts, but the investigators note that new objectives continue to emerge through the ongoing effort. The investigators have a good grasp of complex issues that are important for the management of both mainstem and tributary reservoirs in the Snake River Basin. However, use of the broader literature specific to the objectives is lacking in the summary but perhaps is covered in the peer-reviewed publications.

2. Methods

While the ISRP did not review project methods from their cited literature in detail, the large body of peer-reviewed publications suggests that the methods used by this project were scientifically sound.

Note: the proponents suggest that projects 200203200 and 199102900 should be combined. As well, can the results be folded into life-cycle models (LCM)? What additional data would be needed to integrate into an LCM?

3. Results

Overall, this research has informed many management decisions in the Snake River Basin and the effort directly addresses several critical uncertainties (CUs), including issues involving reservoir management, species interactions, predation, invasive species, and density dependence. Some project findings are relevant to issues outside the Basin (e.g., the importance of reservoirs for rearing over winter, river velocity, food webs).

The proponents have conducted extensive investigations over many years; their results are important for several reasons:

• The increased court-ordered spill has increased TDG in the lower Snake and Columbia rivers. The project’s results are directly applicable to understanding the effects of water temperature and dissolved gas effects on migrating Chinook. It seems that the first objective has been met.
• The researchers are documenting recent changes to the Snake River food web that affect not only Fall Chinook salmon, but all salmonids emigrating from the Snake River Basin. One concern, however, is that the project is focused on too few species while other potentially important predators, competitors, and prey are not addressed (e.g., channel catfish, other non-native species). As well, the proponents do not address modification to the natural habitat (with respect to effects on food webs) and the effects of chemical contaminants on food web dynamics.

• The otolith research directly addresses uncertainties about which contemporary fall Chinook salmon production areas are most important, where fish rear and overwinter, and what proportions of fish adopt yearling and subyearling life histories. These investigations could potentially provide useful information about carrying capacity and habitat attributes for successful smolt production.

4. 2017 Research Plan uncertainties validation

The project proponents provide a nice synthesis of how their project addresses CUs. It could serve as a model of what the proponents could do in future years. Nevertheless, it was difficult to cross check CU numbers in the narrative with the CU statement in the database or ISAB/RP report. It seems that the online database is missing some CUs that should be directly linked to this project such as Mainstem Habitats 1.2. Also, the investigators show that this project addresses Predation CUs 1.3, 1.4 and 2.1; Climate change CUs 1.3, 1.4, 2.1 and 2.2 (indirect); M&E CUs: 1.1, 1.2, 1.3, 2,1, 2.2. The CU database should be updated. This is true in other projects as well.

 

Adaptive Management and Public Outreach are not addressed as project objectives or activities; they should be integral parts of the project. Development of these objectives/activities and a response outlining the respective strategies for each objective/activity are needed for ISRP review. The proponents have the experience and data to analyze and synthesize specific objectives in considerable depth, and the timing is right for providing broad scientific leadership to help other groups in the Basin and beyond. The lead proponent (Ken Tiffan, USGS) indicated in his presentation that he is working with Billy Connor, retired USFWS, on a complete history of Snake River Fall Chinook as well as two other synthesis articles. Ken Tiffan also indicated that he wants to re-examine University of Idaho professor emeritus Dave Bennett's work on historical conditions in the Snake River. The ISRP encourages the research team to prioritize completion of these syntheses.

Overall, this was a well prepared proposal that meets scientific criteria. The goal of this project is to understand the mechanisms underlying Snake River juvenile fall Chinook salmon life history diversity and its consequences to management activities such as transportation and flow augmentation. It also seeks to quantify mortality risks that ultimately affect population productivity. Investigation of losses of juvenile salmonids to non-indigenous predators in the FCRPS is called for by the 2008 BiOp, the NPCC Fish and Wildlife Program, and the Adaptive Management Implementation Plan (AMIP). The significance of this work to the BiOp objectives and regional plans was well supported. The activities funded by this proposal would not duplicate other efforts. The relationship of this project to other research efforts in the upper Snake River mainstem, particularly the other predation study (199007700), was clearly described. Project proponents made a good effort to differentiate the activities outlined from other studies, including the other large Snake River fall Chinook project (199102900). The personnel have experience in the work elements and are well-qualified to conduct the work.

Progress on this project to date has provided important new information on the early life history and life history diversity of Snake River fall Chinook salmon. Subyearlings migrating from spawning areas in the Clearwater River migrate rapidly in the free-flowing portion, but then slow and delay in the area above the confluence with the Snake River (transition zone). Survival through the confluence area is low, but the survivors grow to relatively large sizes and apparently survive well during subsequent migration and marine life. Over-wintering of juvenile Fall Chinook salmon in the hydrosystem reservoirs has thus been shown to be a viable life history strategy.

The net benefit for survival through the entire life cycle has yet to be determined. Much remains to be learned about the implications of the over-wintering life history strategy for management operations, including bypass, transportation, spill, and summer flow augmentation. The questions being asked (role of predation in limiting survival of overwintering reservoir-type Chinook parr, importance of gas bubble disease, and the influence of water temperature) are difficult to answer in such a large aquatic ecosystem, and the project has shown that it can successfully carry out the large-scale studies and reach scientifically supported conclusions. The proponents have a strong record of peer-reviewed publication of past results.

The proponents also hypothesize that predation is higher now than 15 years ago, especially in summer. This project would produce needed information on current losses of juvenile fall Chinook to predators, updating and expanding on studies done over 20 years ago. Understanding how predation, gas-bubble disease, and temperature interact to affect survival of reservoir-type fall Chinook salmon would be useful for management of the ESU.

For the most part, the technical background, deliverables, work elements, metrics, and methods were adequately described. A few shortcomings in the initial proposal were adequately addressed in the response.

The response explanation for why smallmouth bass and channel catfish were the focus of the predation studies clarified that research on these species was specified in the AMIP and the Council's 2009 Amendments to the Fish & Wildlife Program. The ISRP agrees that these species warrant further study in light of the rapid temperature changes that mark the transition from river to reservoir. We also concur with the proponents that preserving pikeminnow stomachs for later analysis and scanning cormorant nesting locations for PIT tags would be worthwhile if the budget permits.

A more complete description of the experimental feeding chamber was provided as requested, and more details were given about the acclimation procedures for test animals and cover characteristics in the apparatus. This information gives us confidence that the experiment will not involve conditions that are greatly dissimilar to what the subyearling Chinook will actually encounter.

In the response, the proponents provided adequate evidence of the probable resolution ability of the otolith microchemistry methodology, i.e., that fish should be able to be assigned to a specific area of origin. The response to the question about using strontium isotopic signatures to differentiate natural and hatchery origin adults provided a good explanation of what is currently known and why this component of the research is needed in this project. The ISRP suggests that it would be very important for the microchemistry portion of the study to show significant measureable progress in their first year in efforts to differentiate stocks (i.e., verifying the very promising 12 known samples analyzed to date and reported in this response) and in the development of other isotope ratios to help distinguish fish from the Clearwater and Salmon rivers.

The response also clarified that project proponents will continue to use scale analysis to differentiate between unmarked hatchery- and natural-origin fish.

Finally, project proponents suggest that the research may shed light on extending the barging season beyond its current termination date, which could provide for late migrants with a high SAR. This was very helpful information for justifying the project.

Investigation of losses of juvenile salmonids to non-indigenous predators in the FCSRPS is called for by the 2008 BiOp, the NPCC Fish and Wildlife Program, and the Adaptive Management Implementation Plan (AMIP). The significance of this work to the BiOp objectives and regional plans was well supported. This project has provided important new information on the early life history of Snake River fall Chinook salmon. Over-wintering of juvenile fall Chinook salmon in the hydrosystem reservoirs was shown to be a viable life history strategy. This realization has influenced decisions regarding operation of the juvenile bypass systems at Snake River dams and also the transportation program for juvenile fish. Much remains to be learned about the implications of the over-wintering life history strategy for management operations, including bypass, transportation, spill, and summer flow augmentation. Results to date have shown that subyearlings migrating from spawning areas in the Clearwater River migrate rapidly in the free-flowing portion, but then slow and delay in the area above the confluence with the Snake River (transition zone). Survival through the confluence area is low, but the survivors grow to relatively large sizes and apparently survive well during subsequent migration and marine life. The net benefit for survival through the entire life cycle has yet to be determined. They also hypothesize that predation is higher now than 15 years ago, especially in summer. This project would produce needed information on current losses of juvenile fall Chinook to predators, updating and expanding on studies done over 20 years ago. Understanding of how predation, gas-bubble disease, and temperature interact to affect survival of reservoir-type fall Chinook salmon would be useful for management of the ESU. This project is a collaborative effort between the USGS, USFWS, NOAA, PNNL, and the University of Idaho. The activities funded by this proposal would not duplicate other efforts. The relationship of this project to other research efforts in the upper Snake River mainstem, particularly the other predation study (199007700), was clearly described. Project proponents made a good effort to differentiate the activities outlined here from other studies. This was a well-prepared proposal that meets scientific criteria in most respects. The project has contributed to our knowledge of life history diversity in upper Snake River fall Chinook salmon, and its record of publication in peer-reviewed journals is exemplary. The questions being asked (role of predation in limiting survival of overwintering reservoir-type Chinook parr, importance of gas bubble disease, and the influence of water temperature) are difficult to answer in such a large aquatic ecosystem, and the project has shown that it can successfully carry out large-scale studies and reach scientifically supported conclusions. For the most part the deliverables, work elements, metrics, and methods were adequately described. The technical background was adequately summarized. The objectives, in general, were clear although a little more background on how the results of this project could alter transportation strategies for fall Chinook would have been helpful. Project proponents have done a good job of differentiating this project from the other large Snake River fall Chinook project (199102900). The personnel have experience in the work elements and are well-qualified to conduct the work. A response is requested on a few points. A more thorough discussion is needed of why smallmouth bass and channel catfish were selected as the predators of interest out of the suite of potential animals feeding on fall Chinook parr in the lower tributaries and reservoirs of the Snake River. It was not clear how predation from other fish species or birds were to be accounted for in the study. Second, a more complete description of the predation-trial chamber is needed, as well as the methods used to prepare the fish for the feeding trials. How well does the chamber simulate the lower river-reservoir transitional area habitat (e.g., will there be any cover in the chamber for Chinook parr that might emulate what they could use along the shoreline)? According to the proposal, predators will be habituated to juvenile salmonids as food before each trial. Could this cause them to form an unnatural search image for parr, even if alternative prey were present? A hungry predator used to eating small salmonids will likely concentrate on them in an enclosed environment, so what steps will be taken to ensure that the importance of predation will not be overestimated in this experimental setup? Third, some clarification of the expected resolution of the otolith microchemistry work is needed. The otolith microchemistry component would provide a tool to differentiate between natural-origin and hatchery-origin adults returning to the Snake River. This is a necessity in order to determine if ESU recovery goals are met. This tool would potentially also allow determination of the overall life-cycle success of hatchery and natural fish and of different life-history types. In theory, this approach would provide more complete data than available for a smaller number of fish using radio telemetry and would be especially useful for fish too small to radio tag. It is not clear, however, that the methods will produce the desired level of resolution. Hatchery/wild differences may be detectable, but will reservoir versus river or tributary rearing be detectable? Studies in other places have shown that resolution can be an issue, and there is the danger that this technique is being oversold at its present level of resolution and sophistication. Some evidence based on other studies that the desired resolution is obtainable is requested. If the proposed work is highly developmental and evidence of adequate resolution is not available, they should perhaps get a baseline of chemistry in the various habitats before launching into a full-blown investigation. Perhaps a one-year feasibility study should be considered, that if shown to work could be continued and expanded. A limitation that should be further addressed is the assumption that returning adults that have no fin clips or hatchery-implanted tags are of natural origin. What percentages of hatchery-produced fry in various years have had no fin clips or tags? Finally, a summary of how the results of the work could specifically affect transportation strategies will make the project’s relevance and importance more apparent. A little more explanation of how the results of the studies will influence transportation strategies would be useful. The importance of understanding migration timing and the apparent effect of a delayed reservoir-type life history on the SAR parameter was clear, but how will this information be used to adjust barging activities?

All data collected under this project will be made electronically available. The reason it appeared that our data would not be electronically available in the proposal is that the proposal form had a limited number of choices of data storage outlets.  The form appeared to be geared more toward monitoring projects rather than research project, which is what our project is.  The data we propose to collect did not fit neatly into one of the “boxes” in the proposal form.  We do intend to make all data available in whatever format and will upload it to whatever data repository BPA decides.  We just need guidance on how and where you want the data stored.  One suggestion is to make a data repository for each project in Pisces or Taurus.  Data could be uploaded to this repository just like uploading reports, budgets, etc.  This way the data would always stay with the project.  Separate metadata and “Readme” files could be created to explain each dataset.  We anticipate that most of our raw data will be stored in Excel spreadsheets and geospatial data will be stored as grids or shapefiles in ESRI ARC Map.  Again, we have no problems with making our data electronically available.

This is a good proposal from a team with an established track record of success. The level of funding may be contingent on support from the US Army Corps of Engineers (USACE).

The project proposes to obtain primary data that will be essential to refining estimates of smolt-to-adult return rates (SARs), transport, etc for Snake River fall Chinook, particularly the newly recognized reservoir life history, under variable hydrosystem operations. These data and analyses are important to understanding the life history of this Evolutionary Significant Unit (ESU) and to evaluating whether hydrosystem operations can be manipulated to the benefit of the ESU.

The technical background is well developed and the research questions are clearly identified. A couple of the acronyms (e.g., TBR) were not identified and may not be familiar to everyone. The reservoir life history in Snake River fall Chinook is an important new development and deserves study. The complications the reservoir life history causes for the estimation of SARs and for evaluating transportation and in-river survival are clearly explained. The project is clearly related to Updated Proposed Actions in the 2004 BiOp, and to the Council's Research Plan. It does not mention any subbasin plans.

There is text that establishes the relationship between this project and several others addressing Snake River fall Chinook status and hydrosystem operations. Given that the principal investigators are sometimes the same on these different projects, along with the huge budget increase, it would be helpful if there was a table that clearly identified all the data that was being collected by which project for what hypothesis testing. Trying to keep all of this straight is not easy, and therefore it is difficult to identify unnecessary redundancy in these proposals. They all tend to take credit for contributing the data necessary for our current understanding of Snake River fall Chinook.

The history was adequately explained, but without much detail for a project that is requesting so much money (~$4 million per year, much more than in previous years). This was one of the projects that led to a much better understanding of the reservoir life history type, winter behavior and passage through the dams, and various methods of identifying the reservoir-type through scale analysis and genetic markers. Neither the history nor the relationships section differentiates well enough between its work and that of 199102900 (Connor's US Fish and Wildlife Service project). The history section might have gone into more detail about how the results have been used to date in the hydrosystem operations.

Clearly defined, measurable objectives are presented with adequately explained hypotheses and timelines. Excellent fish tracking methods are planned -- acoustic, radio, PIT, all related to hydraulics. The explanation of the experimental design, primary data collections and field methods, and analysis are clear. Because the project involves extensive fish marking it is important to include power analyses in determining appropriate sample sizes, and the proposal does a good job of showing how this was done. Procedures for monitoring and evaluation are thoroughly explained. This work will be applicable to studies of the behavior of other species in other regions of the Columbia River Basin.

The group has excellent facilities, equipment, and personnel. Much equipment is from Corps projects and will be used simultaneously with their work (cost-saving should be explored to reduce the cost to this project). The proposal describes the different ways information will be disseminated. They also include plans for long-term data and meta-data storage at the Pacific Northwest National Laboratory. This group has a fine record of publication.