Ocean Conditions

Adult survival of fall chinook salmon in the ocean was not inordinately low in 1990-1992 when compared to El Nino years, such as 1982-83. Therefore, the overfishing committee concluded that "poor ocean survival rates for adults were probably not a primary factor contributing to recent poor productivity of Klamath River fall chinook salmon" during the years of under-escapement (PFMC, 1993). However, they did find some evidence that ocean survival of juvenile chinook salmon may have contributed to low stock abundance in 1990-1992. This conclusion was based on very low survival rates of Iron Gate Hatchery fall chinook yearling release groups . Studies show that released yearlings usually migrate rapidly downstream and into the ocean; therefore, their poor survival was ascribed to poor ocean conditions.

Hatchery Operation

Iron Gate Hatchery and Trinity River Hatchery operation were evaluated as part of the overfishing committee review. Although evidence was not conclusive, the committee found that hatchery operation may have contributed to poor productivity of the 1986 through 1988 brood years and to subsequent low abundance of Klamath River fall chinook stocks in 1990-1992 (see also Chapter VIII).

Freshwater Habitat Conditions

The overfishing committee also attempted to discover if any major differences in freshwater habitat productivity in the 1986-1988 brood years could have led to declines in 1990-1992 stock abundance. While it is acknowledged that habitat conditions are very unfavorable in some Klamath sub-basins (USFWS, 1991), available data did not provide conclusive evidence that particularly poor survival would have caused declines in recruitment in 1986-1988. The preponderance of professional opinion on the committee, however, was that drought conditions in 1987 and 1988 exacerbated habitat problems for spawning and rearing and made some contribution to under-escapement in 1991-1992.

Mixed Stock Fisheries Problems Not Resolved for South Fork Stocks

When fish of different stocks, including wild fish and abundant hatchery fish, range together they are often harvested in what is termed a "mixed stock fishery." Hatchery fish are sheltered from natural selection during their early life stages; therefore, they are much more capable of sustaining harvest than naturally spawned salmon (Stempel, 1988). If wild salmon are returning to streams with impaired habitat, their reproductive ability may be further diminished making them even more vulnerable to exploitation (Lichatowich and McIntyre, 1987).

Hankin (1992) suggested that naturally spawning Oregon coho salmon would exhibit reduced stock productivity in response to poor freshwater habitat conditions and, to a lesser extent, to poor ocean conditions in some years (Figure 7-10). It has also been suggested that the inability to separately manage for hatchery salmon and depressed wild stocks may be contributing to the extinction of Pacific salmon stocks throughout the Pacific Northwest (Nehlsen et al. 1991; Wright, 1993).

Salmon stocks in the South Fork Trinity River all spawn primarily in the main stem of the river. Changes in bed conditions following the 1964 flood reduced suitability for spawning and rearing (CDWR, 1982) and main river environments still suffer from lingering flood effects (Haskins and Irizarry, 1988). Consequently, salmon stocks from the basin may have low natural stock productivity and impacts from overfishing would be magnified. The following problems with mixed stock harvest in various fisheries may be impacting South Fork Trinity River stocks.

Fall Chinook

The South Fork Trinity River fall chinook population was at a critical low point in 1990, when it was estimated that fewer than 20 females survived to spawn (Jong and Mills, in press). Fall chinook spawn primarily in the canyon area below Hyampom where Dean (personal communication) noted scour and fill of up to ten feet in 1991, a year with very low flows. Rearing conditions in the main stem of the South Fork Trinity River are also poor (Chapter III). Because of severe habitat problems in the South Fork Trinity River basin, there may be no harvestable surplus of wild fall chinook salmon stock from the basin.

Ocean fisheries have constituted the bulk of the harvest in all years until 1991 and 1992; therefore, they would pose the greatest threat to South Fork fall chinook stocks. Sport harvests in the lower Klamath and Trinity Rivers that target abundant hatchery fish may also create mixed stock fisheries pressure on South Fork fall chinook salmon. Problems already noted with regard to low escapement in Klamath River basins above Weitchpec (PFMC, 1993a) may lead to a shift in timing of Indian net harvest to target Trinity River Hatchery fish instead of Iron Gate Hatchery stocks. Since South Fork Trinity River fall chinook have a similar run timing to Trinity River hatchery fish, this effort shift may have an undesirable impact on the depressed natural stock of the South Fork.

Estimated Changes in Sustained Yield Curves in Response to Freshwater Habitat and Ocean Conditions

Figure 7-10. Estimated difference in sustained yield of Oregon coho salmon in response to impaired freshwater habitat conditions and years of poor ocean conditions (from Hankin, 1992).

Spring Chinook

There are no specific escapement goals for any stock of naturally spawning spring chinook salmon in the Klamath basin. Ocean harvest monitoring of this stock group is not routinely employed to achieve harvest rate management, as it is for fall chinook salmon, yet they are known to be impacted in ocean fisheries, particularly by the commercial troll fleet (KFMC, 1992). South Fork Trinity River spring chinook also are experiencing problems with their freshwater habitat and the population has been at critically low levels since 1964 (see Chapter II). Healed ocean hook scars were seen on South Fork Trinity River spring chinook in 1990 (Dean, in press), confirming that the stock is vulnerable to ocean harvest.

USFWS (1990) expressed concern that increased Indian fishing effort, in response to abundant Trinity Hatchery spring chinook, could potentially impact depressed wild stocks. Dean (in press) found that 25% of South Fork Trinity River spring chinook had gill net scarring in 1990, but the rate dropped to 8% in 1991. Dean (in press) also found that 12% of spring chinook returning to the South Fork Trinity River in 1990 had fresh hook scars indicating some harvest by in-river sport fisheries. No fresh hook scars were seen in 1991 when fishing within the South Fork itself was restricted.

Coho Salmon

No management effort has been expended by PFMC or other entities to determine if there is a harvestable surplus of coho salmon from California's rivers, including Klamath basin stocks (PFMC, 1992). California coho salmon are thought to range along the Continental Shelf from Monterey, California to the mouth of the Columbia River (Hassler, 1985). Take of coho salmon is governed by estimated abundance of Oregon coastal natural coho stocks (KFMC, 1992). Oregon wild coho were over-fished from 1989-91 (PFMC, 1992a). High production of hatchery fish, over-estimation of abundance of wild fish, and poor freshwater habitat conditions were all cited as contributing to the over-fishing problem on Oregon coastal natural coho (PFMC, 1992a).

South Fork Trinity River coho stocks may be at extremely low levels (see Chapter II), but the contribution of harvest to low abundance is unclear. The number of coho harvested annually in the California ocean troll increased after 1963, supported largely by artificial production in Oregon and Washington (O'Brien and Lesh, 1975). Studies by Nickleson et al. (1985) showed that Oregon coho stock composition changed from 50:50 hatchery/wild ratio to 85:15 as a result of an intensified mixed stock fishery targeting hatchery coho. Similar problems with mixed stock harvest would exist for any remnant wild South Fork Trinity River coho stocks after 1964 and would continue to the present. Catches of coho salmon are far higher in the sport fishery in the KMZ than in the commercial troll catch (KFMC, 1992).

Leidy and Leidy (1984) noted that native Klamath basin coho have a significantly later run timing than Trinity River and Iron Gate Hatchery coho. In-river sport and Indian fisheries are not significant during the time that native coho are thought to be migrating.

The major escapement shortfall of Klamath River fall chinook salmon in 1990-1992 has led to discussion of several possible remedies to prevent the recurrence of this problem. Universal marking of hatchery fish and selective harvest in all fisheries, where feasible, is one potential solution that is under consideration. Poaching problems in the Salmon River basin in Siskiyou County have been partially remedied through community education and that example may have some potential for transfer to the South Fork Trinity River basin.

Mass Marking May Be Solution To Mixed Stock Fishery Dilemma

Current Klamath River basin fall chinook salmon management does not have the capability to specifically protect South Fork Trinity River fish. Even when overall escapement goals are met for the aggregate Klamath basin stock group, some sub-basin stocks may be under-escaped (PFMC, 1993a). Neither spring chinook or coho salmon from the Klamath basin are specifically managed for any harvest rate or escapement goal. If more stocks of salmon fall under protection of the Endangered Species Act, fisheries may be closed to prevent extinctions. Conversely, continued harvest of weak stocks in mixed stock fisheries may contribute to extinction of some stock groups in the Klamath/Trinity basin.

Universal marking of hatchery salmon and selective harvest in all fisheries where feasible may be a viable management alternative to allow continued fishing of abundant hatchery fish while relieving pressure on weak stocks and permitting them to recover. If mass marking is employed to protect weak stocks of fall chinook salmon, it would also protect wild spring chinook salmon. Universal marking of coho salmon is currently under consideration by the U.S./Canada Technical Committee of the PFMC (1993b) and, if implemented would afford protection to remnant wild coho stocks in the Klamath basin.

Below is a discussion of the pros and cons of mass marking that relies on a recent CDFG (1993a) analysis.

Marking Methods Available Are Limited: Clipping the adipose fin, a small fleshy fin between the dorsal and tail fins, would be the most desirable mark to help recognize hatchery fish. Adipose fin clips cause less mortality than clipping other fins and are the easiest to see for fishermen trying to release unmarked wild fish. Currently the adipose fin clip is used only in conjunction with implantation of a coded wire tag in the nose of salmon species. The heads of adipose fin clipped fish are retrieved after harvest at many locations to provide information on harvest management and on the effectiveness of various hatchery methods.

To make mass marking feasible, the international convention of mandatory coded wire tagging of all adipose fin clipped fish would have to be abandoned. New technology now allows smaller tags to be implanted in the cheek of juvenile hatchery fish that can subsequently be detected by an electronic sensor similar to ones used in grocery stores. An electronic sensing wand could be used to screen harvested salmon to gather the same information currently available from coded wire tags, but only a fraction of the adipose fin clipped fish would have to be tagged.

Cost and Logistics of Marking Are Substantial: Costs of marking all salmon released from hatcheries throughout the Pacific Northwest would run in the millions of dollars. Iron Gate and Trinity hatcheries produce an average of ten million juvenile chinook salmon annually and Central Valley hatcheries produce approximately 40 million juveniles each year (CDFG 1993b). It is much less expensive to mark only with a fin clip as opposed to a fin clip and coded wire tag. Thus, repealing the international convention of requiring coded wire tags for all adipose fin clipped fish, as discussed above, would be essential to contain the costs of universal marking.

Fingerlings can only be marked after they attain a certain size, and they must be released by late spring. Marking crews might have to operate around the clock to accomplish universal marking in the time frame required. Both the logistical problems and cost could be reduced if the number of hatchery fish released were also reduced. Hatchery production is known to sometimes have deleterious side effects on wild fish (Steward and Bjornn, 1990), and may be a contributing factor to stock losses region wide (Nehlsen et al., 1991). Consequently, the level of hatchery production should probably be re-evaluated to insure that impacts to wild stocks are minimized.

Mortality Associated With Marking: Any marking program can be expected to increase mortality due to handling stress. CDFG (1993b) anticipates up to 5% mortality from adipose fin clipping and suggests that mortality could reduce hatchery production by as much as 5-10%. The greatest problems associated with handling stress are when fish that have disease problems that are in remission are handled. Excessive mortality often thought to be related to marking may actually be indicative of fish health problems that need to be remedied regardless.

Incidental Hooking Mortality On Unmarked Fish: Whenever a fish is hooked and brought to the boat it may suffer mortality from stress or be more subject to predation. Ricker (1976) estimated that incidental hooking mortality of under-sized salmon in troll fisheries might be as high as 50%. More recent studies suggest that realistic hook and release mortality is more in the range of 20% (Wertheimer, 1988). Since large scale hook and release type regulations have never been attempted for commercial and sport salmon fisheries, a great deal of innovation would be required to make such an effort succeed. Therefore, fisheries management would have new challenges such as:

1. Re-evaluation of hooking mortality to confirm that prior studies

are accurate,

2. Determination of impacts to fish with an older age at maturity

(eg. chinook salmon) due to multi-year exposure to fisheries,

3. Shaping fisheries so that effort was discontinued when the

ratio of unmarked to marked fish became too low, and

4. Shifting fishing effort away from areas with a large proportion

of unmarked fish.

Cooperation Could Be Problematic: For mass marking to be successful, all hatcheries throughout the Pacific Northwest would need to cooperate. Changing the convention on coded wire tagging will also take international cooperation. There is considerable resistance to mass marking at present from the California Department of Fish and Game and the government of Canada, among others. The problems of fishing access to stocks resulting from Endangered Species listings and low abundance of some natural stocks is spurring re-evaluation of this option at present (PFMC, 1993b).

Angler Acceptance To Selective Harvest and Enforcement: Traditionally, anglers and commercial fishermen have been able to keep all fish over a certain size limit; therefore, they may react adversely to selective harvest of hatchery fish. Would anglers stop fishing if they were able to keep only a portion of fish hooked? Release of bleeding fish that were almost certainly going to die might produce adverse reactions to this strategy. CDFG (1993b) is apprehensive that selective harvest might suffer rejection by anglers.

Recent regulations requiring release of coho salmon or chinook salmon in various years has already accustomed anglers to some selective harvest. A large scale education program would be necessary, if selective harvest were implemented, to help improve survival of released fish and to gain acceptance for the program. If anglers were aware that without selective harvest there might be much less fishing opportunity, they might be open to this new approach. As consumers become concerned about endangered salmon, they may reduce consumption unless commercial fishermen can assure them that salmon harvested were of hatchery origin.

Any major changes in management and regulation are always accompanied by significant challenges to enforcement personnel. Commercial processing facilities and docks where sportfishing boats returned would need monitoring to assure that only fin clipped fish were being landed. This effort is no different than monitoring use of salmon punch cards by sport anglers, reduced bag limits, or selective harvest of chinook and release of coho salmon in recent years. Preventing unauthorized clipping of fins by commercial or sport fishermen of released wild fish would be a considerable challenge.

Application of Selective Fisheries: In some years it is possible that there might be a harvestable surplus of some wild stock groups leading to lost fishing opportunity on some populations with a harvestable surplus. Hopefully, restoration efforts in freshwater habitat would proceed as selective harvest was implemented, making harvest of wild fish possible again in the future. It is also possible that no harvest of hatchery fish might be allowed in extremely low abundance years. For instance, in 1992 only 7,600 fall chinook salmon returned to Iron Gate and Trinity hatcheries despite almost complete protection from ocean fisheries. In these years of extremely low abundance, hatchery marking costs would seem like a waste.

Policy Issues Need Consideration: CDFG (1993b) suggests that managing fisheries only for hatchery production might lead to increased pressure to boost hatchery output and lessen incentives to protect wild fish and to restore their habitat. However, increased hatchery output of salmon will likely be precluded under the Endangered Species Act because of the undesirable side effects on wild fish. CDFG (1993b) also puts forth the hypothesis that gill net fishing might come under fire because it is not compatible with selective harvest. Conversely, if selective harvest in the ocean were implemented and it led to a tremendous resurgence in returns to the river, Indian harvest might become much less significant relative to escapement.

Community Education Helps Decrease Poaching In Salmon River

Adult education by the Salmon River Concerned Citizens, funded by the Klamath River Task Force, has been successful in reducing poaching in the Salmon River basin (Pete Brucker, personal communication). Workshops were held in the rural communities along the Salmon River (Sommes Bar, Forks of the Salmon and Sawyers Bar) to alert local residents of the critically low population levels of spring chinook salmon and summer steelhead. It was pointed out that listing of these species under the Endangered Species Act could lead to further restrictions of local land management such as timber harvest and mining.

Local residents in the basin have responded positively by decreasing poaching activity. Because fish have been an important supplement to the diet of basin residents in the past, poaching has been acceptable behavior. That social acceptance has now shifted so poachers must now be much more secretive because they are under scrutiny from their neighbors.

The Forks of the Salmon Elementary School has joined in the anti-poaching educational campaign and has produced a poster saying "poach eggs not fish." In the South Fork Trinity River basin, educational efforts for school children are already underway with the Hayfork Adopt-a-Watershed program (see Chapter XIV). Adult workshops on poaching in the basin might also be worthwhile.

Continuation of the current rescue rearing program for winter steelhead on Tule Creek could help provide "hatchery" fish for sport harvest, while helping to build community support for restoration. This program could have maximum benefit if it leads to a fishery on Hayfork Creek that poses minimal threat to wild fish while allowing economic development related to tourism. If the community had legal access to a fishery in Hayfork Creek, poaching might also decrease. Such a fishery could be based on "Wild Trout" regulations with one fish in possession, and use of artificial lures only. Release of wild fish could be stipulated, with only fin-clipped fish allowed for harvest. This would insure that wild fish populations were only minimally impacted. Oregon, Washington, and British Columbia all now manage their steelhead fisheries on a limited kill basis. Hatchery fish may be kept but all wild fish must be released.

Hayfork Creek has clear water conditions compared to other northern California streams that have winter steelhead. An economic development program based on tourism related to winter steelhead fishing might be an outcome of this effort. Drawing anglers that are primarily interested in catch-and-release fishing stimulates the local economy but takes nothing from the local resource base. Hayfork Creek would only be open in its lower reaches (below Salt Creek) during high flows in winter and provisions would be necessary for closure during drought or low flows. If fishermen begin to release wild fish in the main South Fork Trinity River, then wild escapement and production might increase since repeat spawning by steelhead is common in the basin. Conversely, CDFG (1993) feels that harvest of winter steelhead in the South Fork Trinity River is minor and, relative to habitat problems, inconsequential in terms of altering run size. Therefore, further limitations on harvest regulations would not necessarily achieve a measurable positive effect (CDFG, 1993).

The National Marine Fisheries Service has never conducted a full environmental review as to what effect large scale fisheries, such as the whiting (hake) fishery or the anchovy fishery, might be having on the food web that supports salmon stocks in the Pacific Northwest. Recent ocean productivity for chinook salmon has been low even in years when there are no effects from El Nino events. Some prime salmon food sources, such as the Pacific sardine (Sardinops sagax), have been almost wiped out (Figure 7-11). Another important forage species is the northern anchovy (Engraulis mordax) which is at the lowest biomass since the species began to be monitored by NMFS (Figure 7-12). This species has continued to decline in recent years even though fisheries have been reduced (NMFS, 1992). Other potential forage species, such as the eulachon or candle fish (Thaleichthys pacificus), are greatly diminished from historic levels (USFWS, 1991). Juvenile whiting are also of a size that would be suitable for salmon as a food source. It may be desirable for NMFS to begin large scale efforts to determine ecological consequences of other fisheries with regard to depletion of food resources for Pacific salmon.

Figure 7-11. Harvest and biomass estimates for Pacific sardines from 1932-1990 showing near extinction (NMFS, 1992). NOT AVAILABLE IN ELECTRONIC FORMAT

In the early days of ocean commercial salmon fishing, salmon remained abundant in the South Fork Trinity River (Trinity Journal, 1936). Healthy habitat in the basin seemed to allow the population to withstand heavy fishing pressure. Habitat degradation drastically reduced all salmon runs in the basin after the 1964 flood, yet ocean harvest continued to rise. Hatcheries increased production levels to support increased fishing effort, leading to over-harvest of wild fish in the mixed stock fisheries (Rankel,

1980). Because habitat is still impaired in the South Fork Trinity basin, stock productivity of coho salmon, fall chinook salmon and spring chinook salmon may all be low which increases vulnerability to overfishing.

Despite major investments of time and money in management of Klamath River fall chinook stocks, returns in recent years have been among the lowest on record. The overfishing committee report (PFMC, 1993b) may result in some modification of harvest management methodology yet incremental adjustments may not be adequate to address fundamental mixed stock fisheries problems. The lack of ability to govern sub-basin stocks through harvest rate management or escapement goals means that South Fork Trinity River stocks could be driven to extinction even while Klamath basin wide goals were being met.

Figure 7-12. Declines of northern anchovy from 1965-1990 (NMFS, 1992). NOT AVAILABLE IN ELECTRONIC FORMAT

To protect depressed stocks of native fish, universal marking of all hatchery salmon may need to be implemented with selective harvest in all fisheries where feasible. Many problems and challenges will confront fisheries managers if such a major shift in management strategy is attempted but clearly the present system is not working to protect gene resources that will be necessary if restoration is to succeed.