Qualifications:

The ISRP recommends that the proponents describe their responses to the ISRP's comments and suggestions below in their upcoming annual report covering FY 2019 accomplishments.

1.      The project should address the effect of bias resulting from sampling constraints on recommendations for structural and operational changes at Snake and Columbia river dams.

2.      The project should conduct an evaluation of bias resulting from missing summer migrants and inability to sample edge habitat in the estuary which may result in size selectivity.

3.      The project should evaluate whether its resulting data are adequate to determine how best to operate the hydrosystem given the large impact that changing climate and ocean conditions have on survival.

Comment:

The project is commended for acknowledging the limitations of their data and the overlap of their data with CSS.

1. Objectives, Significance to Regional Programs, and Technical Background

The proposal clearly presents project objectives that are of significance to regional programs. Smolt travel and survival estimates from this study have been important in preparation of biological opinions, for operation of the FCRPS, and for tracking progress of regional fish and wildlife efforts in the Columbia Basin.

Objective 2, which is to detect smolts in the Columbia River estuary with the PIT-tag trawl, should be evaluated in terms of accuracy and precision of survival estimates to determine if the results obtained with current efforts are adequate for management purposes.

Objective 4, which is to relate estimates of smolt travel time and smolt survival with adult returns, should be evaluated to determine whether it is possible to have acceptable confidence in how best to operate the hydrosystem given the large impact that changing climate and ocean conditions have on survival.

2. Results and Adaptive Management

Results from this study are used to guide structural and operational changes at Snake and Columbia river dams to improve smolt travel time and survival.

Over the life of the project, results have been shared through a series of annual reports and peer-reviewed journal articles. Project reports are well written. In recent years, fewer journal articles have been published. An explanation of the adaptive management process being used by the project to review and possibly modify its actions is also needed.

3. Methods: Project Relationships, Work Types, and Deliverables

The project uses standard statistical methods. In response to past ISRP reviews the project proponents have satisfactorily considered the limitations of the data collected by the project. Past responses to ISRP reviews stated that the project is not designed to estimate SARs and does not have a sufficient number of smolts tagged to make extensive evaluations of adult returns. It is not clear from the current proposal if this limitation continues.

A response is requested to address the following questions: 1. Is the tagging level of 50-60K sufficient to obtain adequate precision for smolt travel time and survival estimates? Is the sample of tagged fish selected to ensure the estimates are accurate? If not, what is the estimated magnitude of the bias? 2. If 2-3% of smolts are detected in the estuary with PIT tag trawl, is this a source of bias? If so, what is the estimated magnitude of the bias? 3. The sampling season covers 85-90% the season when PIT tagged fish pass. Is this a source of bias? If so, what is the estimated magnitude of bias? What is known about the fish that pass earlier and later? 4. When relating annual estimates of smolt travel time and survival to migration conditions is the tagging level sufficient? Is it excessive? 5. When relating annual estimates of smolt travel time and survival with adult returns is the tagging level sufficient? Is it excessive? This is one of the high priority projects in the Fish and Wildlife Program. It continues to provide critical survival estimates/metrics for tracking recovery and status and trends of listed salmonids. The information provided by this project is central to understanding how survival of migrating juvenile salmonids is affected by operation of the FCRPS. The conditions encountered by migrating fish in the hydropower system change over time: in recent years, new surface bypass structures have been constructed at many mainstem dams, and additional spill is now provided to assist fish passage through the dams. In addition, changing ocean conditions strongly influence smolt-to-adult return rates. Continuation of this project is well justified. Information from this study has been used by managers in the basin to help guide structural and operational changes at Snake and Columbia River dams in order to improve smolt travel time and survival. The travel time and smolt survival data have also been used for development of NOAA’s COMPASS model and continue to be used each year to evaluate COMPASS model performance and to improve the model. The proposal also addresses past concerns about possible overlap with CSS and other studies by stating that some duplication of the critical data and analyses of this and the CSS project is not necessarily bad, but can provide an error check mechanism and instill more confidence if results are consistent. Comparison of information generated by this project with JSATS and POST generated results would be useful. It is unclear from the proposal how the performance of this project has been monitored and evaluated. Evidence should be presented in future proposals to indicate how well this project has been performing and how adaptations based on monitoring of performance have been implemented.

Data and analysis generated by this project are available electronically in table form (word) and figures from our annual reports to the Bonneville Power Administration.  Data include detection probabilities for individual hatchery releases of PIT tag fish, and at dams for as well as survival estimates for these groups and various other groups (wild, hatchery, and wild and hatchery combined for various species.

We do not anticipate making the raw data anymore avialable then this in the future, as the raw data comes from PTAGIS, which is available electronically from the PTAGIS website.