28 August 1998
Mr. Ray Temple
Freshwater Program Manager
Oregon Department of Fish and Wildlife
P.O. Box 59
2501 SW First Ave.
Portland, OR 97207
Dear Ray:
The Oregon Chapter of the American Fisheries Society (ORAFS) appreciates the opportunity to review the spring chinook chapters of the Willamette Basin Fish Management Plan. ORAFS is a volunteer organization of profes sionals in fisheries and aquatic sciences. We have over 500 members in Oregon, representing a diverse mix of scientists in federal, state, and tribal agencies, and in the private sector and higher education. Our Chapter promotes the application of sound science to resource management decisions and we support effective stewardship and conservation for healthy ecosystems and wild fish populations.
Our common interest is chinook salmon recovery, and the maintenance of healthy fisheries consistent with prudent stewardship of wild chinook populations. The Willamette fish management plan focuses on harvest and hatchery management me asures for which the Oregon Department of Fish and Wildlife has direct responsibility, authority and resources. With the proposed federal listing of Willamette Basin spring chinook as a threatened species, conservation and recovery of existing wild spri ng chinook populations must be the central feature of this management plan. The Willamette River spring chinook fishery is a very high profile fishery in Oregon; therefore we expect that harvest management measures – and supporting hatchery production — to receive the greatest scrutiny from members of the public. However, the efficacy of these measures can only be evaluated in the broader context of all factors that limit the production and abundance of spring chinook in the Willamette River basin. Th ese include ocean survival rates, access to appropriate spawning and rearing habitat, and the quality of that habitat. The role of past harvest and hatchery management as a depressing element for wild spring chinook populations needs to be addressed dire ctly. Recovery of Willamette River basin spring chinook will require decisive action in the face of significant scientific uncertainty.
As an initial step toward a spring chinook recovery plan, we suggest that the document would be substantially improved if it were to provide a ecological framework of chinook salmon life history, habitat use, habitat availability, and h istoric trends of abundance, hatchery releases and harvest. A timeline summarizing significant management actions and habitat changes (such as dam closures) would be valuable.
We also suggest that the document include a discussion of the historic and current population structure of Willamette spring chinook as a gene conservation group (ODFW) and as an evolutionarily significant unit (NMFS). The structure an d inter-relationships of large and small populations, the diversity of life history strategies, and the contribution of habitat diversity and early rearing habitats to life history diversity may be very important in establishing a context for conservation and recovery strategies. As written, the document places its principal emphasis on the McKenzie River as a reservoir of wild fish. Conservation and recovery of smaller, less productive wild populations, such as in the North Santiam basin, may be very i mportant to the health of the larger group of populations in the Willamette River basin as a whole.
This background information would provide a valuable context for run size and harvest objectives set forth in several chapters. These appear highly ambitious under present circumstances. The choices of escapement goals, run size trigg ers and harvest rates suggest that an implicit stock-recruit relationship is assumed; we suggest that this assumption be made explicit as an aid to further evaluation. For example, Objective 4 of the chapter addressing the Clackamas River basin sets an o bjective of 400 to 800 fish over North Fork Dam. The supporting rationale cites a time series prior to large increases in hatchery releases. The next objective in this chapter calls for an increase in wild spring chinook spawners to 2900, based on acces s to high quality habitat above North Fork Dam and calculations based on the 1953 Willamette River spring chinook run. Was North Fork Dam closed before or after 1953? Since the stated goal of 2900 spawners is based on 1953 figures, and the document indi cates that year set the all time record Willamette River spring chinook run, we must ask whether it make sense to base a management objective on returns from a unique year? We suggest planning and management will receive broader acceptance as more realis tic and achievable if they are based on typical rather than exceptional conditions.
We fully support the selection of specific escapement goals for river sub-basins within the Willamette River system. However, selection of, and prospects to reach, escapement goals need to be placed in the context of population structu re, harvest rates and habitat changes. What were the commercial and recreational harvest rates during the years contributing to the aforementioned Clackamas River time series? What are the sensitivities of expected escapement numbers to the harvest rate s presented in this plan at aggregate estimated run sizes? What are the assumptions used concerning ocean survival? Do habitat assessments support the assumptions made concerning wild fish production? Perhaps most importantly, is the proposed managemen t regime consistent with the conservation of smaller wild chinook populations in the basin?
You asked ORAFS to address three specific questions in our review of these chapters:
1. does the plan protect genetic resources of Willamette spring chinook?
2. would implementation of the actions and approaches in the plan sustain Willamette spring chinook?
3. does the fishery regime allow rebuilding wild Willamette spring chinook populations to their existing capacities?
We are unable to adequately address the first question. Much of the answer hinges on the whether the standards for compliance with the ODFW Wild Fish Management Policy are adequate to maintain genetic diversity of wi ld stocks. Our reviewers do not have the expertise to address this issue. It is appropriate to incorporate wild fish into hatchery broodstock. However, caution must be exercised to ensure that this not be done to such an extent so as to undermine the s ecurity of the wild populations in question. A related objective in several of the chapters is the maintenance of hatchery fish genetic diversity. Each chapter having this objective has as the only action under the objective to “develop guidelines and a monitoring and evaluation program for all Willamette system spring chinook hatcheries for the retention and utilization of broodstock that protect parental biological characteristics.” The Department may meet this objective if it implements ap propriate guidelines and a monitoring and evaluation program. If the only action is the development of guidelines and monitoring plan, then the objective will likely not be met.
Your second question asks whether the actions and approaches in the plan sustain Willamette spring chinook. The plan addresses only harvest and hatchery management. Conservation of Willamette River spring chinook can only be evaluated in a broader context that includes freshwater and marine habitat conditions and population structure. We re-iterate our suggestion that plan elements be placed into an appropriate ecological context. A risk assessment integrating the current status of Willamette spring chinook with proposed ODFW management actions, habitat protection measures, and actions to be taken by other agencies would be a valuable step toward answering this question. We also encourage the Department to develop a population viab ility analysis (PVA) for this group. A PVA would evaluate extinction risks and recovery prospects based on various harvest and hatchery management strategies combined with a habitat analysis and consideration of natural environmental variation. The resu lts would allow explicit predictions of how proposed management actions may alter risks and growth potential of affected populations.
Your third question asks whether the proposed fishery regime allows rebuilding of Willamette River spring chinook. The answer to this question depends on the nature of the stock-recruit relation assumed by the authors of the plan, the stock-recruit relation actually shown by the fish, and again, the structure of the wild populations in the Willamette River basin. These need to be made explicit. We note that at aggregate runs entering the Willamette River of over 90,000 fish, total ex ploitation rates experienced by some sub-basin populations could be as high as 48% to 65%: 30% recreational in the Columbia and lower Willamette, plus 11.5% commercial exploitation in the Columbia and lower Willamette, and a further 10% to 40% exploitat ion within a sub-basin. [e.g., Willamette above McKenzie objectives 3 and 4; Clackamas objectives 6 and 7]. These rates are exclusive of any ocean fishery mortality prior to entry into the Columbia River system. We believe that these harvest rates are too high to achieve the purpose of rebuilding of Willamette River spring chinook. However, more important questions are (1) whether the aggregate expected run sizes entering the Columbia River which would trigger these high harvest rates are logically co nsistent with the escapement and harvest goals for sub-basins further upstream, and (2) whether the wild fish escapement goals set forth provide for the secure future existence of these stocks. Therefore, we re-iterate our suggestion that a risk assessme nt be performed, and that the assumed stock-recruit relationships be made explicit to allow open examination of these important questions.
We suggest that the harvest and hatchery management approaches presented in these chapters would be more clear if the chapter on mainstem Willamette spring chinook came first, followed by the chapters on the Clackamas, Molalla and Puddi ng, Santiam and Calapooia, McKenzie, and finally the Willamette above the McKenzie. As returning adult chinook migrate upstream, harvest management lower in the river necessarily impacts opportunities and options upriver. Ordering the chapters in this w ay would result in the flow of concepts and information to the reader paralleling the upstream migratory movements of these fish.
We also offer several comments specific to one, or more, of the individual chapters:
1. Conservation, stewardship and recovery of extant wild spring chinook populations must take a more prominent position in this document. While the stated intent of the document is a first step toward a recovery plan for Willamette spring chinook, the two most prominent objectives in each chapter are (1) to achieve full mitigation for Willamette spring chinook populations reduced or extirpated due to dam construction and operations and (2) the maintenance of hatchery fish genetic di versity. This points to a clear emphasis on maintaining fisheries, and the hatcheries that support those fisheries. High hatchery production and harvest almost certainly contributed to the current status of wild spring chinook; discontinuing hatchery re leases in substantial portions of the Willamette River basin to afford wild spring chinook populations the opportunity to respond should be a tool used by the Department until monitoring shows that hatchery releases are not a depressing element for wild p opulations.
2. Several chapters establish increased wild fish return objectives that are based on opening up currently inaccessible habitat areas. An evaluation of this currently inaccessible habitat would be appropriate. As written, the pla n provides no inkling of the pragmatic difficulties, time frame, expense, or potential resistance to such actions. We suggest that public understanding and support of this plan cannot be achieved without providing this context.
3. The assumption that age of return and run timing are genetically inherited characteristics needs elaboration. Both traits would seem to be a blend of genetic and environmental factors. Diversity in life history characteristics is increasingly recognized as an important element in salmonid conservation; conserving the variation in these traits will require environmental diversity as well as genetic diversity in both hatchery and natural settings.
4. The need for, and public benefit from, continued hatchery production when fisheries are closed and are likely to remain so in the near future is unclear. Conversion of hatchery programs from a principal purpose of fish production to a purpose of achieving conservation goals should be thoroughly explored. Several chapters depict hatchery releases to achieve return goals as constant numbers or pounds of fish produced or released. Adult return objectives, the achievement of recovery objectives, and the maintenance of life history and genetic diversity may be attained more readily if hatchery rearing and release conditions encouraged the hatchery population to better reflect the natural diversity of life h istory traits seen in wild populations. An experimental approach to hatchery rearing and release regimes should be investigated.
5. McKenzie spring chinook chapter
a. The first assumption and rationale states that a minimum escapement of 300 spring chinook over Leaburg Dam is assured by closing fisheries below Willamette falls when the predicted Columbia River entering run is below 30,000 fish. This statement would be true only when wild McKenzie River bound spring chinook represent over 1% of the total entering run and there is no significant or disproportionate mortality on this group. Conceptual and evidentiary support for this statement is needed.
b. The same item provides estimates of the proportion of wild spring chinook moving past Leaburg Dam. Since hatchery chinook are not presently marked, it is unclear how these estimates are derived.
c. If a major objective of the Department is to restore wild spring chinook in the McKenzie River, then we suggest suspension of all hatchery releases of spring chinook in the McKenzie River basin for an indefinite period of time.
6. Clackamas spring chinook chapter
a. Action 2.1 calls for fin-marking all hatchery spring chinook beginning in 1997 to permit distinction of wild from hatchery returnees (Action 2.2). Given this, it is unclear why other techniques to distinguish wild from hatchery returnees are advantageous (Action 2.2b). If they are advantageous, why are they not incorporated into the other chapters calling for full marking of hatchery fish?
b. Action 2.3 says ODFW will maintain a minimum escapement of 300 wild spring chinook over North Fork Dam, while Objective 4 calls for an escapement range of 400 to 800 individuals. If 300 can be achieved simply as a Departmental ac tion, why is getting to 400 conceptually or pragmatically more difficult?
c. Are the escapement goals presented under Objective 5 based on typical or exceptional returns? Is it realistic to meet this objective on a sustained basis, even granting the optimistic assumptions of restored access to upper water shed habitat?
d. How will the average annual run size to the Clackamas basin be increased to 12,400 if hatchery production remains constant? Doesn’t this objective postulate a significant increase in marine survival? What percentage increase in post-smolt survival would be needed to meet this objective?
e. It is unclear how increasing average annual catch in the Clackamas basin to 5000 fish is consistent with sustaining wild populations as a primary management consideration.
7. Mainstem Willamette Spring Chinook
a. As noted in our general comments, aggregate harvest rates may be too high to protect small stocks. This is a classic management problem involving mixed-stock fisheries. More detailed examination of specific a ssumptions concerning abundance, population structure and stock-recruit relationships will be important to assuring the public that an appropriately cautious approach is being adopted.
b. The harvest rates presented are apparently intended to be interim until full marking of hatchery fish allows selective sport fisheries. It will be important that incidental hooking mortality in these postulated selective fisherie s be estimated; an assumption of 0% wild fish mortality in hatchery-only fisheries is likely unrealistic.
8. Molalla and Pudding River Spring Chinook; Santiam and Calapooia Spring Chinook
a. We are somewhat confused by the apparent contrast between (a) Objective 2 of the Santiam and Calapooia Chapter (protect gene resources of North Santiam spring chinook) and (b) assumption/rationale 3 under Objec tive 7 of the same chapter (wild chinook protection to have priority over catch in the Santiam Basin) with (c) assumption/rationale 1 under Objective 2 (defers management of the North Santiam wild chinook population for Wild Fish Management Policy complia nce pending status clarification). Under the current circumstances of poor understanding, a proposed Endangered Species Act listing, and few wild spring chinook populations in the Willamette River basin, we suggest that North Santiam spring chinook be ma naged to ensure WFMP compliance as an appropriate precautionary measure.
b. Both chapters contain unsupported assumptions concerning the availability and abundance of appropriate habitat to support natural production. The bases for these assumptions should be discussed, particularly given that spring ch inook have evidently been extirpated from some areas with appropriate habitat.
c. Both chapters call for an increase in natural production, and note the vulnerability of returning adults to harassment and illegal harvest. We suggest that a linked management action be increased enforcement to reduce these activ ities to insignificant levels.
Returning to the stated goal of this document as a first offering toward a spring chinook recovery plan, we strongly encourage ODFW to take a leadership role in this effort. To that end, we suggest that ODFW address the need for other actions needed to recover this group. These include:
1. Historic habitat changes. The mainstem Willamette has changed dramatically since the coming of Europeans to Oregon. The plan assumes that the mainstem is used principally for smolt migration. We currently do not know enough abo ut the life history of spring chinook in the Willamette to say what habitat is important or limiting. Similarly, we are unable to tell whether certain life history patterns contribute disproportionately to returning adult numbers.
2. Existing habitat. The plan needs greater attention and detail on what will be done to recover and protect historic spring chinook habitat that is still accessible. Re-establishing access to habitat above dams is important, but w e still have significant problems to overcome with upstream and downstream passage at dams and through reservoirs. The significance of historic spawning and rearing habitat inundated by reservoirs is unknown. We recognize that ODFW does not have auth ority in this area, but habitat quality and use is a critical element in Willamette spring chinook recovery. We encourage ODFW to take the lead.
3. Re-establishing natural production in several different river systems will be important for the recovery of spring chinook above Willamette Falls. Sustainable runs in smaller rivers will likely require reducing aggregate harvest impacts downriver to protect weaker stocks.
We appreciate the opportunity to provide comments on the spring chinook chapters of the Willamette Basin Fish Management Plan. Please feel free to call on us if you have any questions.
Sincerely,
Hal Weeks, President for the Executive Committee
c. S. Foster, Chair, Oregon Fish & Wildlife Commission
P. Bisson, AFS Western Division
G. Griffin, NMFS Portland
B. McPherson, ODFW
C. Corrarino, ODFW
J. Myron, OR Trout