Qualification: In two years, the project proponents should provide a report on genotyping, success with the identification of stray hatchery fish, capture of adults and smolts in the target streams, and exclusion of hatchery adults in the target stream. At that time there needs to be a thorough presentation of the BACI experimental design to ensure it will be sufficient to evaluate genetic and demographic effects of straying.

The goal of this project is to measure the effects of stray hatchery steelhead, released from hatcheries in other subbasins with the Columbia River using a BACI manipulative experiment. These stray hatchery steelhead enter the Deschutes River, apparently to seek refuge in the cool water, and unknown numbers remain and spawn with wild Deschutes River steelhead. These data are critical because these hatchery steelhead routinely make up between 50% and 10 times the abundance of wild spawning steelhead, and the effects of this swamping are unknown.

The work is well planned, using proven methods, and has been refined several times through the proposal process. The results stand to help managers understand whether supplementation of steelhead in other parts of the Columbia River Basin can aid in sustaining and recovering wild stocks, or whether supplementation is another factor contributing to their demise through unanticipated effects that play out at long distances in other basins.

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

The investigators propose to evaluate the relative reproductive success (RRS) of stray hatchery and wild steelhead in two eastside tributaries of the Deschutes River, and to remove hatchery strays from a treatment stream and compare the RRS of these wild steelhead to those in a control stream (see comments on the experimental design in number 4 below).

The proposal is of great significance to regional programs. The effects of these strays could threaten the wild stocks of mid-Columbia steelhead, which are a threatened DPS, with extinction, when added to other stressors like climate change. Moreover, no comprehensive evaluation has yet been made of the effects of stray hatchery steelhead on wild fish.

The investigators have carefully planned a decade-long project, tested the adult traps, and include a conservation geneticist who is skilled in parentage analysis from another project (on Abernathy Creek, WA).

The objectives and methods are reasonable, the general design simple and elegant, and the data collection and analysis well planned (including power analysis). If anything, it would be ideal (if funding were available) to add another set of treatment and control tributaries, perhaps westside tributaries. This would make another statistical “block” which could be compared with the eastside block to determine whether any effects are stronger or weaker between these two environments.


2. History: Accomplishments, Results, and Adaptive Management

This is a new project, so there are no accomplishments or results to report, except the pilot testing of adult traps, which was successful. This project has the potential to be important information for managers, to assess how supplementation and removal of strays could be better managed.

3. Project Relationships, Emerging Limiting Factors, and Tailored Questions for Type of Work (Hatchery, RME, Tagging)

This project links to others that seek to understand the effects of hatchery fish on wild fish reproductive success. As such, the set of projects stand to provide managers with much useful data to understand whether supplementation is a useful practice, with minimal impact, or whether it is another factor contributing to the demise of wild fish populations.

Climate change is identified as an emerging limiting factor, which may be exacerbated by stray hatchery fish, if the latter reduce reproductive success of wild fish.

4. Deliverables, Work Elements, Metrics, and Methods

Two points on methods and deliverables, first is the genotyping. The proposal indicates that SNP markers using Parental Based Tagging will be used to identify the source of stray hatchery fish and also to determine the RRS of hatchery and natural steelhead adults. This is reasonable, but those methods are under development and may not be sufficient. They need to be evaluated before a full commitment is made to use this genetic marker and identify stray hatchery individuals.

Second, it is not entirely clear to the ISRP how the treatment and control (reference) streams will be managed. The proposal states:

“The study design is a Before After Control Impact with the treatment of removing hatchery strays from Bakeoven and allowing strays to continue to enter and spawn at the normal rate in Buck Hollow Creek for the first phase of the study and then removing strays from Buck Hollow after the initial treatment in Bakeoven. This design allows for assessment of changes in productivity and survival between the treatment and control streams as well as a pre and post comparison in the control stream, Buck Hollow. For five years we will remove all hatchery fish from Bakeoven Creek and allow only wild fish to pass and spawn naturally. In Buck Hollow Creek, we will allow all wild and stray hatchery fish to pass upstream to spawn naturally for the first five years and then remove all hatchery strays there after.”

The proposal appears ambiguous to the ISRP on the subject of whether stray hatchery steelhead will be permitted access to Bakeoven Creek after the initial five year period. The ISRP believes the experimental design likely requires continued removal of hatchery fish from both locations throughout the duration of the breeding portion of the investigation. During phase two, strays probably need to be removed from both streams.

The ISRP’s rationale is that at the beginning of this experiment the assumption is that both natural populations of steelhead are genetically equivalent and have had many years of hatchery fish introgression. There is a genetic and environmental (density dependence) cost to having these hatchery fish present. If during the experiment you have two streams, one with hatchery fish present, and another where they are removed, you have two contrasts during those years. One contrast is the hatchery and natural fish in the mixed population, a second contrast is between the natural fish in the two locations. The first contrast measures both the genetic (non-native and hatchery) and environmental (hatchery) costs to the hatchery fish when they spawn. The second contrast (natural with hatchery versus natural without hatchery) measures the environmental effects (density and other ecological) of hatchery fish on natural spawning fitness of natural fish.

Once the treatment period ends (removal of hatchery fish), there is the opportunity to evaluate whether there has been a genetic improvement (genetic effect) in the population where hatchery fish were removed – a contrast of natural fish spawning naturally that are now genetically different. During the breeding period for this contrast the ISRP believes there should be an absence of hatchery-origin steelhead in both environments.

The ISRP believes that a full evaluation of the experimental design, with an explanation of all the RRS comparisons and their biological interpretation is required before full implementation.

Qualification: In two years, the project proponents should provide a report on genotyping, success with the identification of stray hatchery fish, capture of adults and smolts in the target streams, and exclusion of hatchery adults in the target stream. At that time there needs to be a thorough presentation of the BACI experimental design to ensure it will be sufficient to evaluate genetic and demographic effects of straying. The goal of this project is to measure the effects of stray hatchery steelhead, released from hatcheries in other subbasins with the Columbia River using a BACI manipulative experiment. These stray hatchery steelhead enter the Deschutes River, apparently to seek refuge in the cool water, and unknown numbers remain and spawn with wild Deschutes River steelhead. These data are critical because these hatchery steelhead routinely make up between 50% and 10 times the abundance of wild spawning steelhead, and the effects of this swamping are unknown. The work is well planned, using proven methods, and has been refined several times through the proposal process. The results stand to help managers understand whether supplementation of steelhead in other parts of the Columbia River Basin can aid in sustaining and recovering wild stocks, or whether supplementation is another factor contributing to their demise through unanticipated effects that play out at long distances in other basins. 1. Purpose, Significance to Regional Programs, Technical Background, and Objectives The investigators propose to evaluate the relative reproductive success (RRS) of stray hatchery and wild steelhead in two eastside tributaries of the Deschutes River, and to remove hatchery strays from a treatment stream and compare the RRS of these wild steelhead to those in a control stream (see comments on the experimental design in number 4 below). The proposal is of great significance to regional programs. The effects of these strays could threaten the wild stocks of mid-Columbia steelhead, which are a threatened DPS, with extinction, when added to other stressors like climate change. Moreover, no comprehensive evaluation has yet been made of the effects of stray hatchery steelhead on wild fish. The investigators have carefully planned a decade-long project, tested the adult traps, and include a conservation geneticist who is skilled in parentage analysis from another project (on Abernathy Creek, WA). The objectives and methods are reasonable, the general design simple and elegant, and the data collection and analysis well planned (including power analysis). If anything, it would be ideal (if funding were available) to add another set of treatment and control tributaries, perhaps westside tributaries. This would make another statistical “block” which could be compared with the eastside block to determine whether any effects are stronger or weaker between these two environments. 2. History: Accomplishments, Results, and Adaptive Management This is a new project, so there are no accomplishments or results to report, except the pilot testing of adult traps, which was successful. This project has the potential to be important information for managers, to assess how supplementation and removal of strays could be better managed. 3. Project Relationships, Emerging Limiting Factors, and Tailored Questions for Type of Work (Hatchery, RME, Tagging) This project links to others that seek to understand the effects of hatchery fish on wild fish reproductive success. As such, the set of projects stand to provide managers with much useful data to understand whether supplementation is a useful practice, with minimal impact, or whether it is another factor contributing to the demise of wild fish populations. Climate change is identified as an emerging limiting factor, which may be exacerbated by stray hatchery fish, if the latter reduce reproductive success of wild fish. 4. Deliverables, Work Elements, Metrics, and Methods Two points on methods and deliverables, first is the genotyping. The proposal indicates that SNP markers using Parental Based Tagging will be used to identify the source of stray hatchery fish and also to determine the RRS of hatchery and natural steelhead adults. This is reasonable, but those methods are under development and may not be sufficient. They need to be evaluated before a full commitment is made to use this genetic marker and identify stray hatchery individuals. Second, it is not entirely clear to the ISRP how the treatment and control (reference) streams will be managed. The proposal states: “The study design is a Before After Control Impact with the treatment of removing hatchery strays from Bakeoven and allowing strays to continue to enter and spawn at the normal rate in Buck Hollow Creek for the first phase of the study and then removing strays from Buck Hollow after the initial treatment in Bakeoven. This design allows for assessment of changes in productivity and survival between the treatment and control streams as well as a pre and post comparison in the control stream, Buck Hollow. For five years we will remove all hatchery fish from Bakeoven Creek and allow only wild fish to pass and spawn naturally. In Buck Hollow Creek, we will allow all wild and stray hatchery fish to pass upstream to spawn naturally for the first five years and then remove all hatchery strays there after.” The proposal appears ambiguous to the ISRP on the subject of whether stray hatchery steelhead will be permitted access to Bakeoven Creek after the initial five year period. The ISRP believes the experimental design likely requires continued removal of hatchery fish from both locations throughout the duration of the breeding portion of the investigation. During phase two, strays probably need to be removed from both streams. The ISRP’s rationale is that at the beginning of this experiment the assumption is that both natural populations of steelhead are genetically equivalent and have had many years of hatchery fish introgression. There is a genetic and environmental (density dependence) cost to having these hatchery fish present. If during the experiment you have two streams, one with hatchery fish present, and another where they are removed, you have two contrasts during those years. One contrast is the hatchery and natural fish in the mixed population, a second contrast is between the natural fish in the two locations. The first contrast measures both the genetic (non-native and hatchery) and environmental (hatchery) costs to the hatchery fish when they spawn. The second contrast (natural with hatchery versus natural without hatchery) measures the environmental effects (density and other ecological) of hatchery fish on natural spawning fitness of natural fish. Once the treatment period ends (removal of hatchery fish), there is the opportunity to evaluate whether there has been a genetic improvement (genetic effect) in the population where hatchery fish were removed – a contrast of natural fish spawning naturally that are now genetically different. During the breeding period for this contrast the ISRP believes there should be an absence of hatchery-origin steelhead in both environments. The ISRP believes that a full evaluation of the experimental design, with an explanation of all the RRS comparisons and their biological interpretation is required before full implementation.

This project is a basic monitoring project intended to investigate the extent and consequences of steelhead straying into the Deschutes subbasin. Out of subbasin straying of steelhead is a growing issue with the increase in hatchery production throughout the basin. The technical background is extensive. The table with values of strays into the Deschutes is convincing that there is need to explore the impact to wild fish (2X wild in some years and locations). Also, the proposal presents a solid of the potential issues, including likelihood of introgression with wild fish where hatchery fish have purposely been excluded from release.

The proposed work, including the expected work in the out-years, addresses a fundamental uncertainty regarding the extent and effects of out-of-subbasin strays on wild steelhead populations. The project has four objectives that relate specifically to high priority issues identified in the Deschutes Subbasin Plan for steelhead.

The work should be applicable to other situations and other species as well. The project is specifically related to other projects (especially M&E projects) and will share resources to accomplish tasks. While the project will focus on a single treatment and a single control stream within the subbasin, results should have at least a modicum of "range finding" value to other situations in the larger basin.

We reviewed a number of proposals aimed at undertaking parentage analysis. The description of the work is relatively thin and implies there is a standard set of protocols and experimental design for such work (which ISRP does not judge to be the case). This fact points to a general basinwide need to begin coordinating such work among groups, with other parentage studies, and with steelhead microsatellite work group for standard sampling and lab protocols.

The sponsors could enhance the robustness of the sampling if multiple treatment and control reaches were included (recognizing this would incur larger costs and effort). Sponsors should at least address this issue as a limitation in its broader applicability.

The ISRP's fundable recommendation is qualified because the proposal would be improved if the following items were clarified (the ISRP is not asking to review a response):
How feasible/possible is it to "remove all hatchery fish from Bakeoven Creek"? Juveniles (parr?) are to be examined to assess reproductive success. Might not smolt recruits be a more robust response variable? Are there prior experiences or attempts that can guide the efficacy of the approach?

How feasible are the proposed field sampling protocols? How do we know that the adult and smolt traps are going to work at the desired efficiencies in BakeOven Creek, for example. Are there prior experiences or attempts that can guide the efficacy of the approach?

How feasible are the adult steelhead traps? Are there prior experiences or attempts that can guide the efficacy of the approach?

There is some vagueness in analytical approach in Objective 3. For example, "...will apply appropriate parametric and non-parametric statistical tests," might be strengthened to include the basic approach (e.g., compare means, variance, covariance, etc. - although not necessarily the "specific" test).