Saturday, November 21, 2009

NOAA Fisheries Calls For Improved Fish Management

The following quotes are taken from a guidance letter from the National Marine Fisheries Service to the state and tribal fish managers for monitoring recovery of ESA-listed salmonids (2009). This guidance document would vastly improve management for wild, native salmonids and provide the basis for recovery of ESA protected fish, and it is similar to adopted criteria for Atlantic salmon conservation in Eastern Canada. These criteria place conservation management emphasis on specific stream management and a conservation requirement for each river and each stock of salmon. This upgraded management is needed on the Pacific coast and this guidance by NOAA Fisheries is scientifically sound and should be carried out by those managing harvest and hatchery programs. There is nothing in this guidance that the fish managers do not already know and have known for many decades, so the issue is compliance. Will the fish managers comply with this guidance? If they do not, then will NMFS do more than make suggestions?

This guidance letter to the fish managers by NOAA Fisheries improves management of harvest and hatcheries so that ESA-listed salmon and steelhead can be recovered and all wild, native populations can be managed for health and productivity. It recognizes that the more these populations are aggregated into large groups for harvest and hatchery programs the more risk individual populations are exposed to, making fish management less likely to protect individual populations. The long history of this kind of management has brought us threatened species, extinction, loss of productivity, restricted fisheries and has wasted public funds.


“Harvest of listed species, though incidental can have a major impact on small populations.

“It is important that the management agencies and tribes directing harvest regimes can demonstrate that harvest is not a threat to recovery.

“In the past hatchery fish have been used to determine harvest percentages in coastal fisheries because they are easily accessed and marked with a CWT (coded wire tag). It has been assumed that nearby natural stocks will migrate in a similar manner to hatchery fish and also encounter fisheries in a similar manner. These assumptions may not hold true for many populations.

“These tag recoveries have been used in run reconstruction scenarios to estimate the percent harvest and harvest exploitation rate in each of the identified coastal and inland fisheries. Although this system provided huge improvements in stock management, the “stocks” managed have been by necessity aggregates of hatchery and wild populations based upon assumed common migration routes and common geographic origins. Hatchery CWT recoveries have been used as the surrogate for estimating interceptions of wild populations as part of stock aggregates but not successful in delineating individual populations within the stock aggregate.

“It is recognized that stock aggregates no longer provide the management resolution necessary for estimating harvest impact to recovering populations listed under the ESA. (emphasis added) Therefore, either a shift must be made from stock aggregate management to population management, or existing fisheries will no longer be able to function due to the inability to quantify their jeopardy impact on listed populations and ESUs.

“Harvest curtailment to address ESA listed species has been used as a strategy to increase spawner escapements and therefore viability of listed populations. However, monitoring is needed to demonstrate that these strategies have been effective in meeting the desired reduction in interception of ESA populations.

“Because harvest removes potential spawners from the population and thus reduces the potential number of eggs that could be deposited and the potential number of emergent fry available to fill the habitat, it is important to understand what impact exploitation rate regimes are having on the rate of recovery in terms of time and spatial distribution.

“If it can be shown that the number of available spawners is fully capable of seeding all available habitats, then recovery rates will depend upon improvements in habitat or some other threat. If it cannot be demonstrated that sufficient spawners are available to fully seed the habitat, then any allowable exploitation rate will potentially prolong the recovery process. Those impacts should be modeled and available for all recovery participants to evaluate.

“Monitoring of natural origin adults should demonstrate that harvest exploitation rates on natural origin listed populations were minimal and that the escapements necessary for building populations back to target viability levels were achieved.

“In conjunction with selective harvest strategies targeting hatchery fish, the states and tribes should continue their evaluation of selective fishing gear and methods to demonstrate reductions in impacts to natural origin spawners.

“The effectiveness of harvest curtailment strategies is validated when the adult to adult productivity ratios are calculated and the percent of total natural production that is harvested is determined to be at the level that does not interfere with meeting or achieving viability productivity goals.

“Although spawner abundance is the defining information needed to determine viability, one of the metrics of interest to those working toward recovery is the total number of adults returning from the sea and how did harvest affect the number available for spawning and recovery. This metric is crucial in validating that the management actions taken by federal, state, and tribal harvest managers have been sufficient.”


“Although it is challenging to quantify the impact of changes in specific diversity traits, such as run timing or age at maturity, on eventual population and species persistence, one likely outcome of adverse changes in diversity is loss of reproductive success.

“…hatchery reared fish are believed to genetically diverge from wild fish as they adapt to survive in the novel hatchery environment. A number of studies (e.g. (Leider, 1990); (Kostow 2003); (Berejikian 2004; (Araki 2008) have reported that when such hatchery fish return and spawn under natural stream conditions among themselves or with a wild fish, their ability to produce viable offspring is much reduced relative to paired wild fish in the same environment. The magnitude of this difference has generally been found to be quite large and may be related to population productivity. For example, Chilcote (2003) found that a spawning population of equal numbers of hatchery and wild steelhead would produce up to 63% fewer recruits per spawner than one comprised entirely of wild fish. If these findings can be applied broadly, then there could be situations where wild production of smolts could be increased by up to three times by restoring genetic diversity to the natural wild populations where such diversity has been lost and by excluding hatchery fish from spawning areas so that additional erosion of genetic fitness cannot occur. (Emphasis added)

“…a successful (integrated hatchery) program would have few hatchery fish straying into the spawning grounds and many natural fish available for cross spawning in the hatchery. “

(Note: This suggests that integrated hatchery programs are dependent upon having access to viable, healthy and abundant wild salmonids in order to function properly While the HSRG prescription is to allow a fraction of the natural spawners to be hatchery fish, this statement takes a more cautious approach. Based on the best available science, there is no justification to manage for an integrated hatchery program recommended by the HSRG. The integrated hatchery program would mine depleted wild populations for eggs and allow hatchery-origin fish to spawn with wild fish, causing further depletion of wild salmonid populations while blending them so that they are more like hatchery fish. Since this HSRG theory has not been tested, applying it broadly throughout the West Coast would be scientifically indefensible.)

“…growing evidence has indicated that hatcheries can have substantial adverse impacts upon wild populations due to competition, genetic introgression, harvest exploitation rates and disease.

“McElhany (2000) concluded that valid estimates of natural productivity are impossible to obtain for supplemented populations in which the abundance of naturally produced and hatchery produced fish on the spawning grounds are not estimated separately.

“…we are recommending that all hatchery fish not marked externally be coded wire tagged so that they are detectable with CWT wands in the fisheries, at counting facilities, and on the spawning grounds.

“Programs need to monitor the genetic characteristics of brood stock to prevent the homogenization of the stock or alteration of gene flow over time. Baseline genetic monitoring is essential and should support current GSI (genetic stock identification) work with salmonids across the Pacific Northwest.” (Emphasis added)

(Note: In the1994 Fish and Wildlife Program adopted by the Power Planning and Conservation Council I was successful in securing a genetics baseline study for the Columbia River Basin, however, this was never funded.)


Crawford, Bruce A. and Scott Rumsey. June 12, 2009. Guidance for monitoring recovery of Pacific Northwest salmon and steelhead listed under the federal Endangered Species Act (Idaho, Oregon, and Washington) National Marine Fisheries Service. Northwest Region. Pp 129.

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