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.
Health of Salmon Populations in Fish River Drainages and Golovin Bay
Written
in part by each of the following:
White Mountain High School AbstractThe Fish River has runs of all five species of Pacific salmon. These species include Oncorhynchus tshawytscha (chinook), Oncorhynchus gorbuscha (pink), Oncorhynchus nerka (sockeye), Oncorhynchus kisutch (coho), and Oncorhynchus keta (chum). The chinook run is weak, but has been getting stronger over the years. The pink runs are very strong on even numbered years and very weak on odd years. The sockeye run is practically nonexistent both historically and presently. The coho run was once strong, but both commercial and subsistence catches have been declining over the years. The chum run is still large but is decreasing.
IntroductionWhite Mountain is a small village on the Seward Peninsula with a population of about two hundred (Figure 1). The Fish River runs right in front of town and is our main source of salmon. It drains into the Golovin Bay which is off the Norton Sound. When we say "our area" we will be talking about the Fish River and its tributaries, Golovin Bay and the Norton Sound. There isn't any commercial fishing in the Fish River, but there are many sport and subsistence fishermen. All of the species of Pacific salmon are found in the vicinity of White Mountain. A great deal of the information we have comes from aerial surveys done by the Department of Fish and Game, and also from the counting tower (Figure 2) that was recently built on the Niukluk River, a tributary of the Fish River. We are going to discuss each of the species of salmon separately because each run is unique.
Chinook SalmonIn the Fish River area, the run of the chinook salmon is in the development stage. Every year, the number of chinook in the Fish River has been increasing. Until recently, there has been no real chinook run, only a couple here and there. The chinook run has been gradually getting stronger over the years.In 1995, from around June 23 until about August 18, roughly 125 chinook salmon passed by the Niukluk counting tower. About 90 of those chinook salmon passed between July 1 and 21. Afterwards the run leveled off (Figure 3, Rob 1998). In 1996, about 225 chinook salmon passed by the Niukluk counting tower. Nearly 190 of them passed between about June 1 and about July 7. Thereafter, very few additional chinook passed (Rob 1998). In 1997, about 285 chinook passed through the Niukluk counting tower, but then about 35 swam back through with the final count at about 250. Between about June 27 and July 7, about 250 of those 285 fished passed through. Then the run slowly started to level off (Figure 3, Rob 1998). In 1998, the same amount of chinook passed through as in 1997, about 250. Nearly all 250 fish passed through between July 4 and July 19. There were very few after that time (Figure 3, Rob 1998). Because chinook don't have a strong history in the Fish River area, Fish and Game doesn't keep very close track of them here. It has been difficult to find information specifically related to chinook runs on the Fish River. Chinook salmon, or Oncorhynchus tshawytscha, more commonly known as "King salmon" because of their immense size, are a novelty to the area(Delaney). Very few anglers in White Mountain have caught even one by rod and reel. The main method of chinook fishing in the Fish River is with a set net. A net is set halfway across the river and left there. About once a day, the net is pulled up, the fish are retrieved, and then the net is set back into the water for another day. The holes in the net are small enough to catch chinook, but large enough to let the majority of other types of fish pass through. Only about two or three chinook salmon nets are set on the Fish River each year. They are set in all different part of the river. Chinooks aren't fished commercially in our area, but are in areas close by. When they are caught commercially near us, they are occasionally mixed with an abundance of another fish. For example, if commercial fishermen were fishing for coho, they might find one or two chinook in their catch each time they pull up the net. One problem that the people of the Fish River have with chinook is that there just aren't enough. Only a few are caught each year. One solution might be the setting of hatchery boxes in the bottom of the river. Another solution could be to impose a restriction for a number of years where no chinook were allowed to be caught so that they could spawn in greater amounts and, hopefully, raise the population. An area near the Fish River where an abundance of chinook salmon are caught commercially is the Norton Sound. We suggest studying the rivers that flow into the Norton Sound that have strong chinook runs and try to isolate factors that have contributed to the run's strength. From 1960 to 2000 a total of 4,118,630 pounds of chinook salmon have been caught in the Norton Sound(Figure 4,Brennan et al., 1999). The amount of chinook commercially caught seems to be on the rise overall; however, it rises and falls dramatically from year to year. For example, in 1985, 419,331 pounds of chinook were caught and in 1992, 57, 571 pounds of chinook were taken (Figure 4,Brennan et al., 1999). On the other hand, as you can see from the graph, there has been a very slow increase in the pounds caught annually. In conclusion, according to the available information, commercially in the Norton Sound region, chinook are being caught increasingly, in greater amounts on odd years. We believe chinook fishing on the Fish River will slowly improve, but that it will always be an honor to catch one.
Pink SalmonIn the Fish River area pink salmon, Oncorhynchus gorbuscha, are more commonly known as "humpies", have strong runs on even numbered years(AK Department of Fish and Game 1999 Norton Sound, Yukon River and Kuskokwim Area bulletin). On these years subsistence fishers catch a lot of "humpies" to cut and dry for the winter. Only 5,000 fish were caught for subsistence purposes in 1995 while almost 12,000 fish caught in 1996. The pattern continues in 1997 with a mere 3,000 fish taken by subsistence fisherman and in 1998 with about 8,000 pinks caught (Figure 5, Northwest Alaska Subsistence Salmon Harvests 1995-1998).Most subsistence fisherman in the Fish River area catch most of their fish by seining. People go seining using a boat in the river and drop a net around fish and use the boat to drag the net full of "humpies" back to the bank. They then put the fish into the boat and bring them back to their camps to cut and hang. Most people like pinks because they dry fast and taste good. On odd years, since there aren't many pinks, the people must catch the less desirable fish, chum. Chum aren't as desirable as pink because they are more difficult to dry and don't taste as good. In an even year, subsistence fishers in our area catch about 200 fish a day (Lincoln, 1999) and do this all week except Sundays. Sport fishers don't really care for pinks because they are small and do not fight very well. Commercial fishing in Golovin Bay between the early 1960s through 1978 wasn't as good as the fishing during 1979 to 1986. There was almost 90,000 fish caught in 1985. Pink fishing was poorer in the early 1990s and but went up to almost 110,00 fish caught in 1998 (Figure 6, Brennan E. L. et al., 1999). Our only problem with pinks is that the runs are small on odd years. Families that rely on them for subsistence suffer in those years because they depend on the fish all winter. One theory that may explain why the pink run is small on odd years is that there was a huge storm about ten years ago. This storm caused the river to become extremely swift and dirty. The river could have carried some of the eggs down river killing them or covering them with silt. Then, on even years, there are too many pinks in the river. People can't even catch half of the fish. Their spawned out bodies wash up on the banks of the river by the tens of thousands creating a horrible stench and temporarily contaminate the river water drinking supply. One way we could help even out the years is to possibly remove eggs from the river and store them cryogenically and then return them to the river the following year. This could then even out the runs and eliminate the "feast and famine" two year cycle.
Sockeye SalmonSockeye live in fresh water for a few months after hatching, but don't start to grow until they reach the ocean. Once in the ocean they grow rapidly while feeding on zoo-plankton, larva fish, small adult fish and, sometimes, squid. (http://www.johnnyseastriverlodge.com/salmon.html) In fresh water sockeye feed mainly on small insects and zoo-plankton. They return to their "home stream" after spending about four years in the ocean. (http://www.johnnyseastriverlodge.com/salmon.html)In the Golovin Bay/Fish River Drainage area sockeye salmon, or Oncorhynchus nerka, (Alaska Department of Fish and Game Wildlife Notebook Series http://www.state.ak.us/adfg/notebook/fish/sockeye.htm) only make up a small fraction of the total salmon run. In fact, on average only 59 sockeyes (Brennan et al., 1998) are caught by subsistence and commercial fisheries in this area each year. In 1988, however, over 900 sockeyes were taken for these combined purposes (Figure 7, Brennan et al. 1998). This shows that the fish are prized and will be taken when available. In White Mountain, between the years of 1995 and 1998, the estimated total of sockeye salmon caught by subsistence fishermen is 85 (Alaska Department of Fish and Game Northwest Alaska Subsistence Salmon Harvests 1995-1998). Between the years of 1962 and 1998 the combined sockeye total of commercial and subsistence fishing is 2,128 (Figure 7, Brennan et al., 1998). Looking at these results you can see that sockeye are not very abundant in our area. Over the years sockeye have been taken in more and more by subsistence fishermen. From 1985 to 1998 the amount of sockeye caught by subsistence fishermen has increased from about 150 to 500 (Figure 9, Brennan et al., 1998). Commercial fishermen take advantage of sockeye runs whenever they happen. Between the years of 1962 and 1998 over 1,000 sockeyes have been taken in. (Figure 10, Brennan et al., 1998). The most abundant year was 1988 with 921 sockeye.(Brennan et al., 1998) Due to the small size of our village an indoor hatchery is not feasible without large subsides from outside sources. The most feasible way to enhance our sockeye run is to put hatchery boxes in the middle of the river where the water is deep enough to prevent ice problems and there is sufficient current to supply oxygen and remove wastes. These hatchery boxes would have to have holes in them big enough to let the fry leave, but small enough to keep trout and other predators from entering and eating the fry. If the fry survive their swim to the ocean, then after about a four year period these adult sockeye will come back to the Fish River to lay eggs. If this process goes on for years our sockeye population will increase. These hatchery boxes will have to be taken out before the river breaks up so that the moving ice will not crush them. We expect that a good amount of the fry will have already migrated by this time. If fry still remain in hatchery boxes, they will be removed and introduced into the rivers. Hatchery boxes have been shown to reduce salmon egg and fry mortality due to predation by up to 100 percent. (Alaska Department of Fish and Game, personal communication) Obviously sockeyes are valuable and desirable both as food and for economic activities. Unfortunately, the runs are so small that without enhancement their potential will remain underutilized.
Coho SalmonFor sport fishing, the most popular salmonid species in our area is Oncorhynchus kisutch (Webster's 1990), or coho salmon. It is also commonly called silver salmon. Some residents in our village also seine coho for cooking and making smoked fish. However, the recent population decline of the coho salmon has limited the use of coho and caused alarm. In 1999, the population was so low that the Fish River was closed for fishing.The coho passage in the Niukluk River is somewhat like a roller coaster. In 1984, there was a very strong run with a count of over 3,000, but the following year there was a sharp drop with the resulting count of about 300. 1988 had a count of almost 1,100, but again dropped the next year. 1991 began the gradual rise of coho with a count of almost 1,800. Then, in 1994, the count again dropped, but rose back up to over 2,100 in 1995. Since then, there has been continuous decline. None of the high counts, though, were close to that of 1984(Figure 11 Brennan, et al., 1999). These counts indicate that the coho is dwindling. The commercial fishing industry in our area has also been on a decline for awhile(Figure 12). In 1994, the Norton Sound commercial fishing fleet caught 100 thousand coho salmon.(1994 Alaska Commercial Salmon Harvests, 1999) The following year, 50 page 17 thousand coho salmon were caught, half the previous year. (1995 Alaska Commercial Salmon Harvests, 1999) It went up a little to 70 thousand in 1996 (1996 Alaska Commercial Salmon Harvests, 1999), but plummeted back down to a low of 30 thousand the following year. (1997 Alaska Commercial Salmon Harvests, 1999) 1998 also had 30 thousand coho salmon. (1998 Alaska Commercial Salmon Harvests, 1999) The exact number of commercially caught coho in 1999 for the Norton Sound area is not yet available, but experts predict that the numbers were low. It is well known to avid trout fishermen that where there are salmon eggs, there are trout. Trout get an easy meal feeding on the eggs. Also, in the spring, these same fish will fill themselves up with the hatching salmon fry. (Kristian, www.anglingbc.com/kkristian/trout.htm) The Fish River has an overabundance of trout. Swarms of trout devour countless thousands of salmon fry as they migrate down the river toward the open sea. You can often see the trout gorging on the salmon fry. They'll eat until their stomachs can't hold anymore which is about 50 to 60 fry per trout. In total, probably thousands of fry become fish food(Ferkinhoff, 1999). It's most likely that the eating habits of the trout play an important part in the decline of the coho salmon population. If people could be encouraged to catch more trout by means of seine, rod and reel, or any other method, it would increase the salmon fry's survival rate immensely. The less predators there are in the Fish River, the more survivors.
Chum SalmonChum salmon, Oncorhynchus keta, are found abundantly in the Fish River. They are traditionally called "dog salmon" because of their teeth. We've never noticed any differences in their population, but all data shows that in the past decade chum salmon returns have been low (ADFG 1999 Fishery Update, 8-31-99).In the Fish and Niukluk Rivers chum salmon are only caught by subsistence fishers. They are most commonly used as a source of dried fish. Chum are caught for subsistence purposes as well as commercially in the Golovin Bay and Norton Sound. Figure 13 (Brennan et al., 1999) shows commercial and subsistence chum catches since 1962 in the Golovin Bay subdistrict. In years when commercial catches were high, subsistence catches were also high. Figure 13 also shows that the general amount of chum caught in the White Mountain/Golovin area is generally decreasing. Most of this decline has occurred over the past ten years. Figure 14 (Rob, 1998) shows the cumulative passage of chum past the Niukluk River counting tower from 1995 to 1998. Each year the overall amount of chum passing the tower is decreasing. The Fish River doesn't have a counting tower, but a similar trend in abundance is likely. Figure 15 shows a similar trend in Fish River and Niukluk River escapement. From the information that we have acquired it is evident that the population of chum salmon is shrinking. This must be caused by overfishing. Since Eskimos have been using the chum for subsistence purposes in this area for at least 1,000 years without damaging the chum run, it is logical to conclude that the decrease must be attributed to excessive commercial fishing on the high seas. We would like some method to identify Fish River chums so that we can better control their commercial harvest while they are in the ocean. This decrease might also be caused by a shift in water current patterns. This shift would affect water temperature and the distribution of nutrients inducing a deleterious influence on primary production. This would zap the food chain at the first trophic level.
ConclusionSo far in our report we have put forth a number of ideas that we feel would be beneficial to the salmon runs in the Fish River drainage. Since all of your ideas cost money and money is in limited supply we have prioritized our list from least to most important. We suggest studying the rivers that flow into the Norton Sound that have strong runs and try to isolate factors that have contributed to the run's strength. We also recommend setting up a DNA data base so that it is possible to determine when fish from our area are being caught on the high seas. This data could help us determine whether the problem exists in our river, or is simply a manifestation of excessive commercial capture of Fish River salmon while they are in the ocean. Another idea is to possibly remove eggs from the river and store them cryogenically, and then return them to the river the following year. We could also place a fish counting tower just below White Mountain over looking a gravel bar which would provide more accurate management information. For some species we feel Fish and Game should impose a restriction for a number of years where no fish were allowed to be caught so that they could spawn in greater amounts and, hopefully, raise the population. Our last and most important solution might be the setting of hatchery boxes in the bottom of the river.Since the fish habitat of the Fish River drainage remains pristine, the single most important factor affecting salmon runs is undoubtedly human harvests. Sufficient information must be gathered so that there can be a fair and sustainable balance between commercial, sport, and subsistence use.
References1994 Alaska Commercial Salmon Harvests-Exvessel ValuesSeptember 16 1999 (http://www.cf.adfg.state.ak.us/geninfo/finfish/salmon/catchval/blusheet/94exves l.htm)
1995 Alaska Commercial Salmon Harvests-Exvessel Values
1996 Alaska Commercial Salmon Harvests-Exvessel Values
1997 Alaska Commercial Salmon Harvests-Exvessel Values
1998 Alaska Commercial Salmon Harvests-Exvessel Values
Alaska Department of Fish and Game
Alaska Department of Fish and Game
Alaska Department of Fish and Game
Brennan E.L., C.F. Lean, F.J. Blue, T. Kohler
Delaney, Kevin "Chinook Salmon"
Delaney, Kevin "Sockeye Salmon"
Ferkinhoff, David P.
Lincoln, Robert T. Sr.
Rob, Peter J.
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