Qualification: Objective 4 currently does not meet scientific review criteria. However, it is an important component of the project, and protocols for the additional work need to be fully described in a study plan and submitted for ISRP review before this objective is implemented.

The proponent has provided adequate responses to most of the Panel's questions with the exception of comments directed to Objective 4. This component, dealing with the question of effects of shad on salmonids, is a key element of the project. An explanation of the experimental design is required – how will this work be conducted? Is this a "natural experiment" that requires years of sampling to cover time periods when shad are abundant and then not? The data collected may allow comparison of age-0 Chinook condition, growth, and survival in locations or years when shad are abundant or zooplankton are scarce, but the analysis of these data was still not entirely clear. The Panel suggests this empirical work could be integrated with proposed bioenergetics modeling and food web analysis.

The ISRP was particularly pleased to see the proponents will broaden their network of biologists involved in the project. Taxonomists and bioenergetics specialists are now involved. The contacts and partnerships with others conducting research on American shad in the region are a positive step. Details of shared tasks and data resulting from these partnerships should be added to the proposal at or prior to contracting with BPA and the Council. The Panel reiterates our suggestion that the proponents contact Dr. Quinn concerning his work on shad in the marine environment as this phase of the life history needs to be integrated into any overall risk assessment for this species in the Columbia River Basin.

The ISRP accepts the proponent's explanation that the original scope of the project was significantly cut due to budget reductions, but it is unfortunate because original food web studies would have provided valuable information regarding shad and juvenile salmonid interactions.

This project has provided interesting, relevant, and previously unknown information on the role of shad in the Columbia River reservoir food web. Several interesting hypotheses pertaining to food web relationships involving juvenile shad have been proposed. These include: shad as a potential competitor with juvenile subyearling fall Chinook migrants; shad as important prey for both native (pikeminnow) and non-native (smallmouth bass) predator species which could improve their growth and survival; shad as prey for subyearling salmon; and shad as disease vectors. Instead of pursuing the broad intent of the project, implied by its title “Impact of American Shad in the Columbia River,” the proposed work narrowed its focus to partially address only the competition hypothesis. The proposal focuses on determining abundance of juvenile shad in reservoirs and estimation of zooplankton abundance, production, and consumption by shad. Even with this narrowed focus, it is unclear, given the data that is to be collected, how the proponents will evaluate whether competition for food between juvenile shad and subyearling Chinook is depressing Chinook growth and abundance in lower Columbia River reservoirs. To even demonstrate the feasibility of a competition hypothesis, with the approach implied in this proposal, many years of data on juvenile shad abundance (preferably over periods when shad both increased and decreased), zooplankton abundance, and subyearling salmon growth and survival would be necessary to provide statistical rigor. If the intent of the proponents is not to address the competition question in a rigorous way, they should say so and indicate how their work is relevant to salmon-shad interactions. The proponents seem to have abandoned their work on food web structure (the encompassing set of hypotheses) in favor of a more narrowly focused project. A great deal is yet to be learned about food web dynamics in Columbia River reservoirs, especially as it relates to its most abundant species, American shad. Competition between shad and salmon does not stand alone, independent of the dynamics of the food web – the complex set of food web interactions that could influence the outcome of competition. In other words, competitive outcomes must be viewed in the context of the entire food web. More fertile ground would be to pursue work on food web dynamics, with competition as a subset of the interactions of importance. Along these lines, it seems that the proponents have enough information on possible species relationships and demographic data on shad, salmon, and pikeminnow to pursue food web modeling, such as the loop analyses done by Hiram Li and Phil Rossignol at Oregon State. We recommend that the proponents work with investigators with food web expertise such as Rossignol and Li to improve the project. Specific components that need clarification in a response: 1. Methods to determine competition between shad and other fishes need to be expanded upon, because to show competition, food must be shown to be limiting, and that issue is not being investigated. Are the proponents able to facilitate an accompanying program on juvenile salmon? Partnering with biologists working on juvenile salmon ecology is strongly encouraged. 2. The proponents raise the concern that a nonnative copepod could be supporting shad. However, no mention was made of, for example, determining whether these zooplankters make up a high proportion of the zooplantion biomass and production, or assessing diets of juvenile shad from those caught in purse seines, to determine what proportion of shad diets they make up. It is necessary to have information on a) how the datasets will be analyzed to address the main question of whether shad affect zooplankton, or vice versa, b) whether the nonnative invasive copepod is increasing and influencing zooplankton production and shad abundance, and c) whether shad are making use of the invasive copepod, as suspected. 3. How is this project related to the USGS’s BiOp proposal #2008-719-00 to study non-native predator impacts on salmon? 4. Shad can be stopped at Bonneville Dam with a fishery and/or fish ladder modification. Would the proponents recommend this action? 5. Shad are declining coastwide. Are the proponents in contact with shad researchers elsewhere on the coast to help look for common factors, perhaps in the ocean, relating to the decline? In particular, Dr. Tom Quinn at the University of Washington has a student working on shad coastwide and the ISRP recommends coordination with the UW project. 6. The nematode Anisakis simplex is found in adult American shad in Oregon rivers (see Shields BA, Bird P, Liss WJ. et al. 2002. The nematode Anisakis simplex in American shad (Alosa sapidissima) in two Oregon rivers. J Parasito. 88(5):1033-1035). Have the proponents looked for this parasite in shad and/or considered the effect of this nematode on shad in the Columbia River? 1. Purpose, Significance to Regional Programs, Technical Background, and Objectives This project responds well to the Council’s MERR plan because the plan calls for studies to evaluate positive and negative impacts of American shad on salmon, sturgeon, and other species as well as the feasibility and advisability of shad management measures. The Fish and Wildlife Program and the BiOp also identify the need for understanding the impacts of shad on listed salmonids. Shad are clearly superabundant in the lower river and an understanding of their role is important. An issue, however, is what can managers do about shad if they are found to be a competitor with juvenile salmon? Shad could be controlled by modification of passage structures in mainstem dams. However, as this non-native has been in the Columbia River for several decades, control could cause cascading effects within the ecosystem (e.g., Zavaleta, E. S., R. J. Hobbs, and H. A. Mooney. 2001. Viewing invasive species removal in a whole ecosystem context. Trends in Ecology and Evolution 16:454-459). Research on adapting to their presence by using them as fish food in hatcheries (assuming the disease problem can be resolved) is an example of what could be done with them. The technical background is well done, and the proponents have a watching brief on new data from shad projects in the species’ native range. However, the proponents have not covered the invasive literature very well. A reference that covers the topic well and includes high fecundity animals such as American shad is Rilov, G. and J.A. Crooks (Eds.) 2009. Biological Invasions in Marine Ecosystems: Ecological, Management and Geographic Perspectives Ecological Studies Volume 204. Springer. The sampling and analysis methods look sound, but the ISRP requests that the investigators present more information on the ultimate analysis. That is, once data on shad abundance in reservoirs, and zooplankton biomass and production, are derived, what will be done with them? Will a bioenergetics model be used to determine whether shad abundance can deplete zooplankton to levels that will stress juvenile salmon? Will investigators attempt to determine whether zooplankton limit juvenile shad during certain periods in certain reservoirs? Likewise, the concern that a nonnative copepod could be supporting shad was not fully explored in the proposal (response item 2 above). These seem like opportunities missed. 2. History: Accomplishments, Results, and Adaptive Management The proponents have provided documentation of their accomplishments and results. Information gained should allow managers to consider options for near-term management of shad in the system, including prospects for control of this non-native fish. A key finding is the likely influence of disease on shad survival. If the population crash of the species continues, will shad continue to be a problem? Disease and thiamine deficiencies might be key limiting factors but the scope and nature of the problem is still evolving. The investigators appear to be starting to publish the data they have collected since 2007 in the peer-reviewed literature, which is a good sign of progress, and a key to ensuring a strong basis on which future research and management can be built 3. Project Relationships, Emerging Limiting Factors, and Tailored Questions for Type of Work (Hatchery, RME, Tagging) The proposal would be improved by increasing ties with biologists working on juvenile salmonid ecology so that a more comprehensive view of emerging factors affecting food webs can be achieved. It is a daunting task to document competition and an ecosystem approach is required. The investigators discuss the potential for a nonnative zooplankton to change dynamics, but it would be helpful to present information on how or whether density or biomass of this nonnative will be estimated from plankton samples. Is this also an objective of the work, as an emerging limiting factor? Climate change may be driving changes in water temperatures or other physical drivers, which in turn may be causing changes in disease or nonnative invasions. Information on plans to assess the importance of factors related to climate change as drivers of American shad would be a useful addition to the proposal. 4. Deliverables, Work Elements, Metrics, and Methods Methods to determine competition are not well thought out, because to show competition, food must be shown to be limiting. An accompanying program on juvenile salmon is required. Partnering with biologist working on juvenile salmon ecology is strongly encouraged. The other work elements, metrics, and sampling methods are well established and scientifically defensible. Reporting has been done on-time. It was good to see several peer review publications in press or under way, and input to AFS symposium was excellent. Better links are needed to these documents. The basic data described as the one deliverable seems suitable, but it seems incomplete without a more detailed analysis of the relationship between shad and zooplankton, as described above. It is unclear how management agencies might use this deliverable to make decisions about American shad management to benefit native fishes, without further analysis.

Fundable with high priority. This is a well thought-out proposal, whose results could be of great significance in the management of salmon, steelhead, sturgeon and other fishes in the Columbia Basin. The ISRP has identified several uncertainties associated with American shad in the Columbia Basin (ISRP Retrospective Report, ISRP 2005-14.) This proposal reviews those and is designed to address them.

A proposal similar to this one was previously submitted by the same proponents under the Innovative Proposal initiative of the Council. The ISRP gave it a high ranking and recommended it for funding. The Council also recommended to BPA that it be funded. However, BPA did not fund it. Because there is so little known about shad in the Columbia River Basin even a small increment of knowledge on their effects on other species would be beneficial.

Technical and scientific background: The proposal clearly identifies and reviews the shad problem. The proponents could have given more details on how they arrived at the four identified hypotheses.

One hypothesis is that there is competition with salmonids for food, which might lead to an effect on growth rate of salmonids. To demonstrate this would require significantly more intensive research than is proposed. The proposed isotope work is not necessarily a short-cut method to arrive at such a conclusion.

Early research summarized in the proposal suggests another hypothesis, that availability of juvenile shad may provide a consistent food source to northern pikeminnow when salmonids are not available, thus contributing to the ultimate size of the pikeminnow population and the associated increase in losses of juvenile salmonids. The shad population is a substantial biomass. A bioenergetics model would be required to analyze the validity of this hypothesis.

Work on other hypotheses (disease, shad as prey, nutrient deficiency) might be appropriate at this time, but not necessarily as part of this proposal.

Rationale and significance to subbasin plans and regional programs: There is no relevant Mainstem Subbasin Plan. However, the questions addressed by this proposal are of considerable significance in implementation of mainstem measures in the Council's Fish and Wildlife Program.

Relationships to other projects: The work is put in context. The proposal would benefit if linkages were shown to several other projects working on food web relationships (e.g., 20030100). Other projects, which might obtain related information are identified, but there are none being conducted on shad per se.

Tasks (work elements) and methods: The proposal does not adequately consider the difficulties in assessing competitive effects on growth and survival of anadromous fish and sturgeon. The simplified food web in the narrative is overly generalized and does not show linkages from invertebrates to algae or detritus from vascular plants. These links, and others, complicate isotope work. Addition of sulfur into the isotope analyses might help. The other components (disease, nutrients, shad as prey) are adequately described and appropriate.

Monitoring and evaluation: The project includes no manipulation, and is itself monitoring in nature.

The facilities, equipment, and personnel are adequate.

Information transfer: There is a good plan for data release, and the proponents have commendable publication records.