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This paper was written as part of the 2000 Alaska Ocean Sciences Bowl high school competition. The conclusions in this report are solely those of the student authors.

Salmon Management

Written in part by each of the following:
Angie Fowler
Jin-Oak Ottoson-McKeen
Jenny Lund
Breanne Rohm
Sam Fox

Team "Poseidon"
Juneau-Douglas High School
10014 Crazy Horse Drive
Juneau, AK 99801

Abstract

Pacific salmon population management poses difficult problems to fisheries biologists all over the state of Alaska, due to the fact that many of the factors which cause fluctuations in population numbers are completely impossible to control. Climate oscillations and regime shifts, otherwise known as aspects of "natural mortality," are considered by many in the scientific community to be the greatest factors in salmon mortality rates. However, this crucial aspect of salmon survival is not within our control capabilities, and therefore we must turn to other means of salmon management.

Factors that influence salmon population levels other than those included in natural mortality are known as either accidental mortality or fishing mortality. This paper is divided into sections describing deaths due to natural, accidental, and fishing mortality.

Like natural mortality, accidental mortality is also different to control, because it refers to fatalities as a result of occurrences such as oil spills and habitat loss. The two main population determinants related to accidental mortality in Southeast Alaska are habitat destruction and hatcheries. In order to decrease the negative effects of these aspects, we must minimize human activities that cause habitat destruction and reevaluate the intended role of hatcheries, as well as verify that they are fulfilling their purpose; helping rather than causing harm to the natural balance of the ecosystem. Fishing mortality, on the other hand, is the one influence that can be controlled and monitored. This paper includes suggestions and comments on the current methods of Alaska salmon management.

Introduction

Managing and controlling Pacific salmon population levels poses difficult problems for fisheries biologists across the state, due to the fact that many of the factors which cause fluctuations in population numbers are completely impossible to control. Perhaps the greatest cause of changes in mortality rate are climate variation and regime shifts. If the Aleutian Low Pressure Index weakens, for any of a number of reasons, Alaskan salmon populations become threatened. Fatalities due to climate changes are part of a larger group of causes for deaths called natural mortality. Natural mortality describes changes in salmon population levels caused by climate, earthquakes, and other natural disasters. In this paper, climate regime shifts and oscillations will be the main aspect of natural mortality discussed, since earthquakes and other natural occurrences are considered to have only minor and short-term effects on salmon survival.

Another cause of salmon fatality is known as accidental mortality. Accidental mortality fatalities account for the unpredictable salmon deaths which occur as a result of human activity. For instance, deaths due to oil spills are called accidental mortality losses. In the region that this paper discusses however, Alaska Department of Fish and Game defined region from right below Juneau to Yakutat, has not recently been drastically affected by oil spills, and therefore we will focus on other types of accidental mortality losses.

The third and last cause for salmon population variations is called fishing mortality including subsistence, commercial, and sport fishing. This group is one of the most critical, since it is the only cause for deaths that can be controlled effectively. This paper will discuss the influences of all three types of fishing on salmon population levels and give recommendations and comments on the current methods of management.

Natural Mortality:

The Relationship Between Long Term Climate Changes and Salmon Growth/Mortality:
In the past, it has been argued that abundance of Pacific salmon could be explained entirely by the effects of fishing. However, we are now beginning to realize that inter-decadal climate variations may truly serve as the determining factor in salmon survival. In 1991, fisheries biologists R. Beamish, D. Noakes, G. McFarlane, and J. King (Department of Fisheries and Oceans, Pacific Biological Station; Canada) noticed a relationship between long-term trends in total Pacific salmon catches and the intensity of the Aleutian Low. Since then, there have been a number of papers written (Beamish, 1998) to demonstrate the convincing relationships between decadal-scale climate trends and trends in salmon productivity.

The fact that our oceans undergo climate regime shifts over extended periods of time can be demonstrated through the study of the 1977 regime shift that helped bring Pacific salmon populations back to a healthy level after their low numbers prior to this shift. One of the tools used to measure these climate changes in Alaska is the Aleutian Low Pressure Index (ALPI). The ALPI (Figure 1) is used as it is associated with physical changes in the sub-arctic Pacific ecosystem (Gargett, 1997). As the ALPI levels drop, temperature begins to rise. These processes have dramatic effects on salmon metabolic rates, as well as other forms of both animal and plant life. When faced with ocean warming, salmon undergo physical changes that can negatively affect their productivity. Increased temperatures impact growth by increasing metabolic demands and reducing food abundance. Before 1977, the ALPI reached all time low levels, but then experienced a dramatic increase, indicating a regime shift. At the same time, salmon productivity also began to increase. In 1989 and 1990, the ALPI began to weaken once again, a trend that has now persisted for 10 years and is approaching the length of the 1977 to 1988 period of intense lows. Thus, some scientists, including Beamish, Noakes, McFarlane, and King, are beginning to suspect that there was another regime shift in 1989 and 1990, although the change was not to a pre-1977 state. Since these regime shifts are not entirely similar, some scientists propose that regime shifts are not cycles with recurring patterns (also known as oscillations), but changes in states that can be multi-dimensional and different every time they occur. The scientific community has not been studying these inter-decadal climate variations long enough to consider them oscillations.

If the associations between the intensity of the low ALPI levels and food production in the 1980s apply to the 1990s, it would be expected that a weakening of the Aleutian Low could be associated with a reduction in food production for salmon in the Gulf of Alaska and Bering Sea. Some fisheries biologists, including Beamish, hypothesize that carrying capacity is determined by a late fall and winter fatality rate that is associated with growth rate during the summer. If this hypothesis is valid, the reduced food and increasing temperatures could increase marine mortalities. "An example of the impact of regime shifts can be seen when analyzing the 1989 change and the synchronous decline in the marine survival of North American southern coho stocks."(Beamish, 1998)

The Relationship between the El Nino Southern Oscillation (ENSO) and Pacific Salmon:
While many scientists, including Yukimasa Ishida of the National Research Institute of Far Seas Fisheries, believe that long-term climate changes and regime shifts should not be considered oscillations, the El Nino Southern Oscillation (ENSO) has been studied long enough and seems to follow predictable patterns to the extent that it can be called an oscillations cycle with confidence. The ENSO events happen on a 3-8 year time cycle and the resulting effects are fairly predictable, even though the controlling mechanism that shifts from El Nino to La Nina and back is unknown. Many biologists believe that these patterns and processes are critical in the ocean ecology of Pacific salmon (Beamish 1995).

In the spring of 1997, a strong El Nino event occurred and extremely high sea surface temperatures (SSTs) were observed in the Gulf of Alaska and Bering Sea during salmon surveys in the North Pacific Ocean conducted by the National Research Institute of Far Seas Fisheries (see Figure 2). In this study, fisheries biologists from the National Research Institute compared SST and relative abundance of Pacific salmon during the 1997 El Nino time period with normal years on the basis of data collected by salmon research vessels in offshore waters from 1991 to 1997, as well as an index rate of pink salmon calculated from coastal catch data in Japan, Russia, Alaska, and Canada for the period 1980-1997, which had four El Nino events and one La Nina event. Through this study, it was discovered that the SSTs of the Bering Sea and Gulf of Alaska in 1997 were on average 1.01 degrees Celsius and 1.81 degrees Celsius warmer than the previous six-year period. It is believed that the higher SSTs are due to the strong El Nino event occurring in the spring of 1997. However, different SSTs were observed in the 1991 and 1992 El Nino years. SSTs were high in the western and central North Pacific in 1991, and SSTs were low in the Bering Sea in 1992. The strength of the El Nino event was different between 1991-92 and 1997-98. Scientists believe that the correlation between high SSTs and El Nino events strongly suggests that the ENSO cycle generally increases the sea surface temperatures of the Gulf of Alaska and Bering Sea. The relative abundance (catch per unit effort, CPUE) of salmon was compared between normal years from 1993 to 1996 and the 1997 El Nino year. Sockeye salmon CPUE increased in the Bering Sea and Gulf of Alaska, but decreased in the western and central North Pacific in 1997. Chum salmon CPUE decreased in the western and central North Pacific. In the Bering Sea, chum salmon CPUE in odd years is usually lower than in even years. However, in 1997, pink salmon CPUE increased in the western and central North Pacific and substantially increased in the Bering Sea, but decreased in the Gulf of Alaska compared to the previous odd-year data (Figures 3-5). Through analyzing this data, it is difficult to see any clear relation between changes in CPUE and El Nino oscillations.

This research seems to show that higher SST levels can have both positive and negative effects on salmon survival rates, depending on the location and species. However, it is generally accepted that overall, elevated SSTs can cause drastic problems in the survival of Pacific salmon, because increased temperatures can cause problematic metabolic changes in salmon, as well as reduce food abundance. This fact is becoming increasingly important in the minds of many fisheries biologists because a regime shift and weakening of the Aleutian Low Pressure Index is predicted. Weather forecasters believe that global warming, as well as long-term climate changes and the ENSO cycle will continue to raise the SSTs of Alaskan waters in the future. Many forecasters have predicted an increase in the frequency of El Nino events, possibly until they have a 2-5 year oscillation pattern instead of a 2-8 year cycle. This means that we can expect increasingly warmer waters, and possibly increasingly lower numbers of Pacific salmon due to higher mortality because of a loss of food abundance and increased metabolic demands.

Accidental Mortality

Introduction:
In order to produce an effective local salmon management plan, we must first define the individual factors that affect the salmon population in our area. Once these factors are defined, we can then move onto the next step of creating ways to control or manage these factors. By incorporating these findings into the salmon management plan, it will allow us to decrease the mortality rate among Pacific salmon and ensure the stability of the salmon industry which has become essential to the economy of Southeast Alaska. The most difficult part of this process is defining the factors that have an impact on local salmon that can be controlled. There are elements such as climate, weather, and other changes in nature that simply cannot be controlled. The variables that we can control include subsistence fishing, commercial fishing, bycatch, habitat destruction etc. All of these determinants can be categorized using the Baranof Catch Equation from the Theory of Fishing (Geiger). The theory states that fish alive at sometime are those that survived 1) natural mortality and 2) fishing mortality. The third cause of death among salmon is accidental mortality.

Accidental mortality includes factors such as logging, mining, and effects of hatcheries, oil spills, habitat destruction, urbanization, and bycatch. Although all of these factors affect the population of Pacific salmon in some way, not all have a direct affect on the local salmon population. For instance, although the Exxon Valdez oil spill was devastating to many parts of the coast of Alaska, it did not have a noticeable, long-term impact on local salmon runs. Similarly, although mining can be destructive to its surrounding environment, not all are by salmon streams. And those that are, such as Greens Creek, are carefully watched and monitored. Therefore, mines are not currently a huge threat to the salmon population in our region.

As you can see, we don't have many problems that we need to find quick solutions for. Compared to states like Washington and Oregon, the salmon population in Alaska has been quite successful. However, salmon returns have begun to decline and the future is unclear as to whether they will continue to fall or not. In preparation, there are two main population determinants that must be addressed in order to maintain our present stability: 1) Minimize human activities that cause habitat destruction 2) Re-evaluate the intended role of hatcheries. And verify that they are fulfilling their purpose; helping, rather than causing harm to, the natural balance of the ecosystem.

Habitat Destruction:
Watersheds in Southeast Alaska are disturbed by both natural events and human activities, however, the effects of these disturbances in fish habitat are generally different. The main differences are related to the rate and the extent of the disturbances of the forested landscapes, and the potential for recovery of disturbed landscapes and fish habitats. Natural disturbances (floods, landslides, insect outbreaks, earthquakes) in fish habitats across forested landscapes can cause negative effects to fish habitat. These disturbances, however, are infrequent and sporadic so whole watersheds are rarely affected by a single event. Also, the time between large natural disturbances such as earthquakes are often in the range of centuries to millennia for any given site. Because usually only a small area of the landscape is affected at any one time, and the disturbances are infrequent, refuges are usually available to assure survival of salmon stocks until the disturbed area recovers naturally, which might take a century or more. Salmon have evolved adaptive strategies to cope with the effects of natural disturbances, and consequently, are rarely placed at risk of extinction from natural events. Human disturbances are typically more frequent and widespread than natural disturbances. The most common forms of human disturbance in forested watersheds of Southeast Alaska are logging and road construction. Projected harvest schedules on Tongass National Forest would mean that the most forested acres on any watershed classified as suitable-available under Tongass Land Management Plan would be harvested during a timber rotation cycle, if allowable sale quantity was maintained throughout the rotation. Because logging is projected for all watersheds containing suitable-available acres during rotation, and could be planned to recur over the entire area for repeated rotations, the disturbance could be relatively frequent in both time and space across the entire landscape subject to timber harvest. The cumulative effects of frequent disturbances in the Pacific Northwest have been shown to substantially reduce the quality of freshwater fish habitats resulting in negative consequences for species, stocks, and populations of fish that depend on them. Fish-bearing streams represent only a small portion of stream mileage in any watershed. Because recovery of fish habitat from the effects of extensive logging in a watershed may take a century or more, recovery may never be complete if forests are clear-cut harvested and watersheds are disturbed extensively on rotation cycles of about 100 years. Few refuges remain in a watershed that fish can use during widespread, intense, and recurrent disturbances. Because extensive large clear-cuts are not regular, natural disturbances of Southeast Alaska, salmon most likely have not developed adaptive strategies to cope with such unnatural disturbances.

Pacific salmon depend on both marine and freshwater environments. (Reproduction takes place in freshwater streams; while maturing takes place in the marine environment.) And salmon populations can become stressed if either marine or freshwater habitat quality declines. Should freshwater habitats be degraded for long periods, salmon will eventually be confronted simultaneously with low marine productivity and degraded freshwater habitat. The likely result of such double jeopardy could be high, long-term risk of extinction (Figure 6).

Negative Effects of Hatcheries:
Alaska is home to one of the most productive and highly valued salmon fisheries of the world. The commercial salmon fisheries yield 160 million pounds (average annual production from Tongass) worth about $250,000,000 annually and provide over 5,000 direct jobs in the Southeast Alaska economy. The subsistence harvest of salmon is in excess of 1.2 million pounds annually. Harvesting salmon in traditional areas is important to sustaining the Tlingit, Haida, and Tsimshian cultures. The long-term conservation of a harvestable surplus of salmon across the Tongass is essential to the economic future of Southeast Alaska.

However, salmon cannot sustain all of Alaska by themselves. This is why there are hatcheries. They increase salmon population, thereby increasing the salmon harvest. Hatcheries produce enough salmon that allows Alaskans to continue to harvest them without drastically affecting the salmon population. This was their intended job. Unfortunately, instead of maintaining a balance and protecting the lives of salmon, hatcheries have succeeded in doing just the opposite. The negative effects of hatcheries include: loss of genetic diversity, competition for food, and imbalance in salmon species.

As many people know, salmon typically return to the same stream in which they were born in order to spawn. This being the case, salmon runs generally evolve independently of each other to their specific stream environment. This genetic diversity is essential to the long-term sustainability of salmon runs. Wild salmon that are genetically diverse are able to adapt to unexpected obstacles that may occur, thereby increasing their chance for survival. On the other hand, hatchery fish have a very narrow gene pool and are genetically unable to adapt to unexpected situations. Because of this, if hatchery fish were transplanted to replenish wild stocks, survival rate and spawning success would dramatically decrease.

Another major consideration when discussing negative effects of hatcheries, is the topic of carrying capacity. A study by V.V Volobuyev (1999) entitled, "Local Chum Salmon Stocks of the Sea of Okhotsk Continental Area and Their Long-Term Changes" has found an inverse relation between the number of fish and the size of fish. The study indicates that a long-term overabundance of salmon may change the permanent biological structure of the stocks. This change in biological structure translates into lower commercial value and fish quality.

The study says that the North Pacific Ocean may have reached its carrying capacity for salmon, and any further increases in stock levels could be disastrous to the species. The study places blame for the overabundance (especially of chum) squarely on hatcheries. In Southeast Alaska alone in 1997; 588,900, 000 fish were released as part of the fisheries enhancement program. These fish compete with wild runs during all stages of the salmon's life cycle. The ocean, once considered an endless source of food for fish, appears to be nearing its limitations for production of food for fish. This limited food is shared by hatchery and wild fish, which results in direct competition for food resources. For wild fish, this means that they go to their spawning grounds smaller and with fewer caloric resources to provide energy for their considerably more strenuous journey, directly resulting in lower success rate for spawning.

Yet another unanticipated problem that is emerging is that between chum salmon and sockeye salmon. Unlike other salmon species, sockeye are immune and natural carriers of the bacterial disease known as infectious hematopoietic necrosis (IHN). However, if there are too many sockeye in a small confined place (such as a hatchery), the IHN levels increase and can be deadly. IHN, which is caused by Flexibacter columnaris, the protozoan parasite Ichthyopthirius multifiliis, and a myxosporean have been variously associated with occurrence of heavy pre-spawning mortalities.

In order to keep the IHN levels down, hatchery sockeye must be kept in small, separate groups. This takes up valued space and money. And most hatcheries can't spare either. This is why there are only two hatcheries directed towards sockeye. (And it takes millions of dollars to keep them running.)

Chum, on the other hand, are precisely the opposite. Chum are both cheap and easy to raise. Unlike sockeye, chum don't need fresh water rearing. Not only are they easy to manage, they can be very profitable as well. A five gallon container of chum eggs can range anywhere between $200-$500. Because of there easy maintenance and high value, Chum are a hatchery favorite. The Juneau hatchery alone released 100 million Chum. Unfortunately, being popular isn't always positive.

Due to the tremendous number of Chum being released by hatcheries, the Sockeye are being effected. A substantial run of chum occurs in the Susitna River in the early May. This is known as the summer Chum run. Numerous runs also enter Prince William Sound destined for Port Wells, the Valdez Arm, and Port Fidalgo areas, as well as the lesser arms and bays. These destinations are similar to those of the Sockeye. Although it is unintentional, fisherman end up accidentally catching schools of Sockeye along with the Chum. Slowly but surely, Chum are becoming overpopulated (due to excessive hatchery release) and the Sockeye population is declining, (due to lack of hatchery release and bycatch) both due to hatcheries. This is not the only example of hatchery wrongdoings.

It is true that salmon hatchery operations in Southeast Alaska have been successful in increasing salmon harvests over the past 10 years. Additionally, hatcheries have added millions of salmon to commercial, sport, and subsistence fisheries. However, an abundance of fish from hatchery supplementation provides no assurance that wild stocks in natural habitats will be maintained. On the contrary, intense fishing pressure on hatchery fish, which are almost always mixed with wild stocks at sea, has been shown to result in the depletion of wild stocks in the Pacific Northwest. Although they are not being addressed immediately, these are problems that will only get worse and will have to be addressed at some point.

Fishing Mortality

Benefits of Hatcheries:
The benefits of hatcheries affect all people who depend on Pacific salmon as an aspect of their economic lives. The main goal of hatcheries is to increase catch opportunities for fishermen and maintain a healthy wild stock population level. Hatcheries can enhance an urban area by increasing and producing runs of salmon every year. For instance in Whittier, a hatchery released a large amount of fingerling coho salmon into the harbor. Two years later, the run returned and provided an abundance of available salmon. Runs produced by hatcheries give people without boats or sophisticated fishing gear a greater chance at successful fishing. Examples of these successful systems that have been installed in regions north of Southeast may be pertinent to our region as well. In Juneau, many fishermen utilize the abundance of hatchery salmon by fishing on the shores adjacent to DIPAC (a local hatchery). Hatcheries can also make fishing more profitable for commercial fishermen. A run of red salmon was introduced to the natural run in Icy Strait. Now, gillnet and seine fishermen can increase profits by catching hatchery fish during the natural stock run. This brings more industry into northern Southeast Alaska, thus boosting the economy. The greatest benefit of producing hatchery salmon stocks is that they relieve pressure off wild runs. The release of hatchery fish takes pressure off wild runs because commercial fishermen catch fewer wild fish, thus increasing the possibility for wild stocks to survive until they reach spawning grounds. Another way hatchery fish benefit wild stocks is that they provide a buffer for suffering wild stocks. Before hatcheries, some fishermen only fished every other year, because in odd years the runs were often so weak that fishing success was minimal. Hatchery fish supplement the weaker run years, so that every year is profitable for both sport and commercial fishing. This brings a regular fishing industry to Southeast Alaska that can support local economies.

Subsistence and Salmon Mortality:
Although subsistence catch records of salmon are not universally maintained, scientists recognize the number of fish harvested as being insignificant when compared to the total statewide catches. For example, of the 151,820,000 salmon harvested state-wide in 1998, subsistence catches only comprised about 1% of the total catch. These catches, although seemingly insignificant in numbers, are of immeasurable importance to native cultures throughout rural Alaska. Subsistence still produces a substantial portion of the state's food supply in rural areas, whose residents comprised about 21% of Alaska's population in 1990 (see figure 7) (Alaska Department of Fish and Game, 1994).

It is estimated that 43.7 lbs. (usable weight) of wild foods are harvested annually by residents in rural areas of Alaska. In 1990, fish comprised 59% of those wild foods harvested (Alaska Department of Fish and Game, 1994). The largest subsistence catches are made in the highest salmon producing river in the world, by Fraser River Indian tribes during the upstream migration of sockeye salmon (Groot, 1991). The average recorded annual subsistence catch for the years 1970-1982 was 240,000, representing an insubstantial 4.7% of the total annual catch of Fraser River sockeye (Starr et al., 1984). The surveyed residents in twenty rural communities from over 1,700 households in Norton Sound, Port Clarence, and Kotzebue Sound, caught an estimated 166,989 salmon in subsistence harvests in 1990, (Alaska Department of Fish and Game, 1998) which further demonstrates the modest levels of subsistence harvests.

Similar to commercial fishing, which is not permitted until salmon runs exceed 625,000 fish, governmental restrictions are placed on subsistence fishermen when projected salmon runs drop to 550,000 or fewer (Alaska Department of Fish and Game,1998). As projected run totals lower, so too, do subsistence fishing hours and openings,thus this system of management can effectively account for fishing mortality and control population levels. The amount of salmon caught through subsistence fishing is so insignificant that it is not taken into account for the hatcheries brood stock in the following year. Nevertheless, if the catch numbers were to increase in magnitude, they could then affect hatchery runs and would subsequently have to be accounted for. However, due to our urban location, subsistence does not play a large factor in our management plan.

Although these subsistence catches are small among the larger-scale commercial catches of salmon in Alaska, subsistence fishing comprises an integral role within the native communities of Alaska. Allowing rural communities to continue with their venerable customs, subsistence fishing is of incomprehensible value to native peoples throughout Alaska, who retain a rich culture backed in tradition practiced for thousands of years.

Commercial:
In 1995, the troll fleet of Southeast Alaska harvested a total of 2,907,400 salmon. Hand troll vessel catches totaled 245,600 fish and power troll boats took 2,661,800 salmon. This harvest included the lowest catch of king salmon ever, a total of 138,100 fish, and the highest catch ever of sockeye salmon, 27,300. This data indicates that king salmon are being harvested at a greater rate than they are able to sustain. Competition between commercial fishermen and the demand for king salmon must not be allowed to influence the total allowable catch values. The numbers of returning salmon have been lower than expected in the past several years with the exception of pink salmon. Therefore, we have concluded that Southeast Alaska salmon stocks would benefit from the appropriation of a percentage or quota system based on total allowable catch figures. The allowable catch would be monitored weekly, thus allowing for variations in salmon survival rates. When the Pacific Salmon Treaty was renegotiated in 1998, this kind of allowable catch system was imposed for transboundary king salmon. According to Alaska Alternate Commissioner Jev Shelton, those involved in writing the treaty are hopeful that this system will be much more successful in managing king salmon stocks. Should a percentage-based system be imposed, it is possible that the price of cannery fish could increase. This could theoretically cause a chain reaction throughout the whole fishing industry, resulting in an increased price for Alaska salmon sold across the nation. Thus, the instillation of a percentage-based system could have positive effects on both the economy of Southeast Alaska and the survival of salmon stocks.

Sport:
In 1996, the total catch of Southeast Alaskan king salmon reached 144,294. Sport fishing accounted for about one fifth of the total catch for these species. The regulations on salmon fishing for residents of Alaska state that six chum, sockeye, pink, and coho may be taken per person, per day. Two king salmon are allowed per person, per day, and the fish taken must be over sixteen inches long. Because of the successful return rates for chum, sockeye, pink, and coho salmon, no changes to the sport fishing regulations for these species are necessary. However, the survival rates of many king salmon stocks are not as healthy, and we therefore recommend that the king salmon bag limit be lowered.

Although there are several hundred charter boats registered in Juneau, only about sixty go out twice a week, which is considered to be an average frequency. Although many boats go out six to seven days a week in the summer, the crew and captain of the fishing vessels do not contribute to the total catch because it is only legal for the paying clients to fish. As Jim Preston, President of the Juneau Charter Boat Association, said "Generally, the client is out for the experience rather than the mass slaughtering of fish to take home to his relatives." Preston determined that the commercial factors which have the greatest impact on fishing mortality caused by charter vessels are 1) limited number of lines put in the water 2) the prohibition of crew member fishing and 3) regulations restricting the number of fish nonresidents can take.

Transboundary Conflicts:

For over a decade, the United States and Canada have argued over rights to salmon that spend time in both countries. Certain Canadian spawned salmon stocks spend most of their time growing and feeding in Alaskan waters, and therefore, many people argue over which country should receive and manage the fishing rights to these salmon.

However, the topic of which country has greater rights to the fish should be set aside from how the fish populations are controlled. To keep salmon survival rates healthy, transboundary fish must be managed from a purely biological, as opposed to political, standpoint. Since 1985, a fairly successful system has been in place as a part of the Pacific Salmon Treaty to control transboundary sockeye from the Stikine and Taku rivers. This system functions on the basis of allowing a percentage of the allowable catch from each river to be taken. For the Taku River, a 85% versus 15% ratio was established to describe the percentage of the total allowable catch that could be taken based on the strength of sockeye stocks from that region. For the Stikine River, a 50% / 50% ratio was established. Because these percentages are based on the total allowable catch which is monitored and revised on a weekly basis, this system has been successful in keeping sockeye population levels healthy.

However, because of political debates over rights to king salmon, a quota system, rather than a percentage system was used for this species until the summer of 1998, when the terms of the Pacific Salmon Treaty were renegotiated. Prior to this, Canada had simply placed a limit of 263,000 king salmon that could be caught each year. However, for stocks from the southerly end of the Canadian border, the number of king salmon caught was more than the populations could sustain. This lead to certain stocks becoming endangered because the quota was not changed from year to year and did not account for variations in king salmon survival rates.

Because of the problems caused by this quota system, last year the treaty was altered to begin utilizing an abundance driven system for king salmon. Based on return rates from this 1999 season, this system seems to be working much more successfully. It is now being realized all across North America that these percentage based systems are most often a positive replacement for quota systems. At any rate, if quota systems are to be used, they must be flexible and subject to change based on salmon survival data.

Conclusions and Recommendations

While climate regime shifts and oscillations cannot be controlled, some aspects of accidental mortality and fishing mortality can and must be managed responsibly. In order to decrease the negative effects caused by aspects of accidental mortality, we must minimize human activities that cause destruction of salmon habitat, and reevaluate the intended role of hatcheries, as well as verify that they are fulfilling their purpose.

The current management plan in place for Alaskan salmon appears to be keeping most of the fatalities related to subsistence fishing at a healthy level. However, commercial and sport fishing regulations could be improved to help reduce the loss of king salmon and increase their population numbers. Currently, king salmon are noted as the most sought after species of the five species of Pacific salmon, and therefore they are fished with extreme persistence. If we can inform the public regarding the dangerous levels of certain king salmon stocks in Southeast Alaska, the added concern could help increase the survival rates of those stocks by decreasing the demand for these king salmon.

Because of the high demand for king salmon, we suggest that a quota or percentage system be imposed, such as the quota system which is in use for halibut fisheries in Southeast Alaska. However, quota system must be subject to change on a weekly basis and should resemble the percentage system based on allowable catch that has recently been established for transboundary king salmon. Based on the success of the percentage systems that have been used to manage sockeye populations of the Stikine and Taku rivers for the last 15 years, we suggest that these types of salmon management concepts should be used to replace less flexible quota systems for all species of salmon within our region, especially for the stocks which are considered endangered.


References

Beamish, R., Noakes D., McLarlane G., King, J. The Regime Concept and Recent Changes in Pacific Salmon Abundance. Department of Fisheries and Oceans, Pacific Biological Station; Canada, 1998.

Brooks, Marthat H., ed. Report to Congress: Anadromous Fish Habitat Assessment. United States Department of Agriculture Forest Service. Pacific Northwest Research Station, Alaska Region. January 1995.

Geiger, Hal. Chief Biometrician, Alaska Department of Fish and Game, (907) 586-1845.

Groot, C., Margolis, L. Pacific Salmon Life Histories. Canada: University of British Columbia Press, 1991.

Preston, Jim. Juneau Charter Boat Operators Association, President, P.O. 210336, Auke Bay, AK 99821, (907) 789-0088.

Welch, David W. Ocean Climate Change and Population Status of British Columbia Salmon in the 1990s. Pacific Biological Station, Nanaimo, B.C. CANADA, 1999.

Sources

Casipit, Cal H. United States Department of Agriculture Forest Service, Subsistence Management. Federal Building, Juneau, Alaska, 99802 (907) 586-7218.

Eggers, D.M., and D.E. Rogers. 1987. The cycle of runs of sockeye salmon (Oncorhynchus nerka) to the Kvichak River, Bristol Bay, Alaska: cyclic dominance or depensatory fishing?

Focht, Rick. Gastineau Salmon Hatchery, Operations Manager, (907) 463-5114. Heritage, Andrew, ed. World Atlas. London, England: DK Publishing, Inc., 1997.

Ishida, Yukimasa. What Happened to Pacific Salmon in the North Pacfic Ocean During the Years of an El Nino Event. National Research Institute of Far Seas Fisheries; Japan, 1998.

Katzeek, David. Sea Alaska Heritage Foundation, Former director, (907) 780-3516.

Shelton, Jev. Alaska Alternate Commissioner for Alaska in the Pacific Salmon Commisson, 1670 Evergreen Av. Juneau, AK 99801, (907) 586-2242.

Starr, P.J., A.T. Charles, and M.A. Henderson. 1984. Reconstruction of British Columbia sockeye salmon (Oncorhynchus nerka) stocks: 1970-1982. Can. MS Rep. Fish. Aquat. Sci. 1780:123 p.

Volobuyev, V.V. Local Chum Salmon Stocks of the Sea of Okhotsk Continental Area and their Long-Term Changes. Magadan Branch; Russia, 1999.

Web Sites

Alaska Department of Fish and Game; Division of Subsistence General Information.

http://www.state.ak.us/local/akpages/FISH.GAME/subsist/subhome.htm. 11/9/99

Alaska Department of Fish and Game; Subsistence. http://www.state.ak.us/local/akpages/FISH.GAME/adfghome.htm. 11/9/99.

Figures


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Figures 3-5

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Figure 7

Figure 7

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Regional Map

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Table 1

Table 1

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