Preservation of Pink Salmon in Carroll Inlet

Transcription

1 Mateer-Olson et. al 1 Preservation of Pink Salmon in Carroll Inlet Team: Saber Toothed Salmon Jessica Mateer Olson, Micah Briola, Keenan Sanderson, Duncan Menzies, Nicole Emmert Ketchikan High School 2610 Fourth Avenue Ketchikan, Alaska Primary Contact: Jessica Mateer Olson jessicamateer@yahoo.com Coach: Julie Landwehr julie.landwehr@kgbsd.org

2 Mateer-Olson et. al 2 Preservation of Pink Salmon in Carroll Inlet Abstract We have chosen the pink salmon index stream near Ketchikan, Alaska called Carroll Inlet for our research paper. Maintaining Carroll Inlet is vital to the survival of pink salmon in this estuary. An array of threats has the potential of affecting pink salmon, the largest being overfishing. To protect these fish from future harm, we propose a management plan that provides guidelines against overfishing as well as plans for tests to be made to make sure that we properly preserve pink salmon within Carroll Inlet.

3 Mateer-Olson et. al 3 Carroll Inlet For many organisms Carroll Inlet is important habitat, breeding ground, and spawning ground. A species that heavily relies on estuaries like Carroll Inlet is pink salmon, also known as Oncorhynchus gorbuscha. While all Pacific salmon spend time in estuaries, pink salmon spend more time than any other salmon. Pink salmon are considered a very important resource economically, even though many in Southeast Alaska who live with salmon in abundance do not hold them in very high regard as a delicacy. However, with their high economic and ecological value it is very important to preserve their habitat and spawning grounds. There are a number of threats to pink salmon in general. Pink salmon face the threat of climate change that can decrease their prey availability in the ocean. One of the worst problems for pink salmon is overfishing (WBGH Educational Foundation & Clear Blue Sky Productions, Inc., 2001). During the 1940s and 1950s, the value of pink salmon was high enough that people used fixed and floating traps to extensively harvest pink salmon. As a result, pink salmon runs declined greatly (ADF&G, 2012). Carroll Inlet is an inlet near Ketchikan that starts off at Herring Bay and extends northeast 26 miles to the Carroll Creek estuary near the center of Revillagigedo Island. This inlet is easily accessible, though not so accessible that there is constant traffic. Carroll Inlet is a prime recreational area with much beautiful scenery, for example the volcanic formation called Painted Peak nearby (Landwehr, 2012). This inlet is also one of the top ten pink salmon producers in the Ketchikan area, and the largest pink salmon stream on Revilla Island (Walker, 2012). For people who sport fish

4 Mateer-Olson et. al 4 and hunt, those who camp, and commercial fishers who come to work, these details all attract them to Carroll Inlet. Estuaries An estuary, such as Carroll Inlet, is where the mouth of a river and the ocean meet and is a complete ecosystem in itself. There are many different organisms that inhabit an estuary: various kinds of fishes, such as pink salmon fry; shellfish, such as clams; mammals, such as harbor seals; and birds, such as herons and eagles. Estuaries are also a prime habitat for oyster farming grounds for the growing shellfish industry in Southeast Alaska (Freitag, 2012). Estuaries are important to Alaska s economy and wildlife because species of great economic and environmental importance such as salmon, herring, and crab depend on these estuaries for temporary or permanent homes. The purpose of this research paper is to explain a management plan and inform people of the importance of pink salmon in estuaries so we can better preserve them not only in Carroll Inlet, but also in all parts of Alaska. Healthy estuaries protect our coastal infrastructure, and allow safe passage to rivers for salmon, both of which provides jobs, recreation, and tourism opportunities. Water that drains from the surrounding watershed carries sediments, nutrients, and other valuable components to estuaries. (Gersh, 2012). The mixing of nutrient rich freshwater with salt water in an estuary allows for abundant growth of microorganisms, which form the basis of the food chain. If the water is polluted, salmon will be negatively affected, as they spend time in the estuary growing. Since healthy estuaries are important to the salmon life cycle, they must be maintained if

5 Mateer-Olson et. al 5 the salmon are to continue using them. If the estuaries are taken care of, those who use estuaries for their livelihood will be able to properly continue working there. Estuaries are important centers of transportation and international commerce as well as important recreational areas. People visit estuaries each year for various recreational activities such as: boating, swimming, bird watching and other wildlife viewing, and fishing. The critical function and location of estuaries gives clear justification for keeping them healthy. (Gersh, 2012) Pink Salmon Life History To better understand the role of estuaries for pink salmon, one needs to look into their life history. Unlike other Pacific salmon, pink salmon don t usually to go too far inland to spawn. Although they have been seen in streams or rivers 250 miles from the ocean, pink salmon will usually spawn in, or slightly upstream of, an estuary. When the eggs hatch, the new salmon swim down river to either an estuary if they were laid in a redd upstream of an estuary, or to the ocean if they were laid in an estuary or other near shore area. After the salmon go through the alevin stage they head out into the open ocean and hide in the gravel of the estuary by day and swim by night. When the salmon fry are in the estuary, birds, other fish, and other animals eat a large percentage of the salmon smolt. During their smolt stage, pink salmon remain in the estuary and eat plankton and larval tunicates (USFWS, 2009). The adult pink salmon start to spawn after about two years. During spawning, they grow a large hump on their back, hence the nickname humpy. Since pink salmon spawn every two years, there are even year and odd year classes. The two have never been known to mix. Pink salmon can spawn any time from June to late September. Pink salmon

6 Mateer-Olson et. al 6 have a weaker sense of home, or homing instinct than the other salmon do, as they sometimes don t come back to the same stream that they hatched from. This is called straying. When the female salmon gets ready to lay her eggs, she pumps her tail to clear some of the gravel and rocks off of where she wants to lay her eggs, also called a redd. Once the female is done laying her eggs, the male salmon fertilize them. The female then moves upstream and does the same movement with her tail to cover the eggs. A female salmon produces multiple redds to mate with multiple males (USFWS, 2009). Economics In the beginning of our paper, we have mentioned that the two main areas that we are focusing on are the environmental and economic aspects of the pink salmon resource. We discovered that pink salmon were of high economic importance not only in our document research, but also had this confirmed by two of the experts we interviewed. These two experts called pink salmon the bread and butter of the local salmon fishing industry (Breese, 2012; Medel, 2012). This is shown in harvest numbers, for example the year with the highest ex vessel price per pound for pink salmon was on the same year that the lowest harvest of fishing in pounds was caught between the years 1980 and In 1988 there was only about 400 million pounds of pink salmon caught but the price per pound was at an all time high of about $0.80 per pound, which was the only time it was over $0.50 per pound. The average price for pink salmon from 1980 to 2011 was approximately $0.25 per pound (Knapp, 2012)[See Graph 3].

7 Mateer-Olson et. al 7 Commercial Harvest History To further demonstrate the economic importance of pink salmon, we explored some harvest numbers. In 1985 the pink salmon harvest began to show its true economic potential. All of the years before 1985, the numbers did not exceed 30 million salmon, with the exception of The largest harvest for commercially caught pink salmon was in the year 1998 and the worst year for commercially caught pink salmon was in 1960 in terms of number of salmon caught (ADF&G, 2012) The commercial fishing harvest of pink salmon is the second largest salmon fishery in Alaska, behind the sockeye salmon, or Oncorhynchus nerka, fishery. The start of the commercial harvest for pink salmon in Alaska was in 1889 but the pink salmon industry took off in From 1980 to 1990 the average harvest of pink salmon was approximately 500 million pounds each year. From 1990 to 2000 the average harvest of pink salmon was approximately 620 million pounds each year. From 2000 to 2011, the average harvest of pink salmon was approximately 550 million pounds each year. Although the chum salmon, Oncorhynchus keta produces more pounds than pink salmon, pink salmon are more abundant than any other salmon. In 2011, the numbers of pink salmon harvested in Southeast Alaska were greater than the numbers for the combined harvest of all the other salmon, with 59,207,000 being pink salmon of the total 115,671,000 that were caught in 2011 [see Chart 1, 2]. (Knapp, 2012).

8 Mateer-Olson et. al 8 Culture In addition to its economic and ecological value, the value of pink salmon as a species is still very important to the cultural groups in Southeast Alaska. For the local tribes: Haida, Tlingit, and Tsimshian, this is one of the five salmon species that they depend on for their food. These native groups depend on the yearly runs to be able to smoke and store the salmon to survive through the winters. Although pink salmon are not considered to be one of the most prized salmon, they still have an impact on the natives. The pink salmon are used for traditional ceremonies, food, and bait to catch halibut and crab. Management Plan In our opinion, a strong management plan should address as many economic and ecological factors as possible. While there is no management plan in place specifically for pink salmon in Carroll Inlet, there are various management plans in place for the different fisheries in the district. Our goal is to incorporate some aspects of each of these plans into our own separate plan. The primary user groups we have put into consideration when making these plans are the following two commercial fishing groups: gillnetters, and purse seiners. We also took into account the ways this would impact sport fishing, as well as cultural implications. Our allocation method is based on the pink salmon escapement numbers from the Alaska Department of Fish and Game, or ADF&G. The goal of our plan is to help preserve, and if possible, increase the pink salmon population Carroll Inlet, as well as preserve the inlet itself, as we previously mentioned in the estuaries section above. To do this we have created a model of a committee we call the CIPSPC (Carroll Inlet Pink Salmon Preservation Committee).

9 Mateer-Olson et. al 9 Carroll Inlet Pink Salmon Preservation Committee Run by one administrator and two workers, as well as volunteers from commercial, charter, sport and native fisheries, this committee would be in charge of making guidelines. Guidelines would include how much the members of the committee would have to pay for the self tax, the quota and harvest limits of each of the different fisheries that would be involved with CIPSPC, and what sort of ongoing scientific monitoring needs to take place to maintain the health of Carroll Inlet. We recommend that representative members have degrees or equivalent work experience in business or economics and science or fisheries. We also recommend that standards are set by the committee in order to complete the work that is determined by the committee. The committee will use the current laws in place for fishing within Carroll Inlet as guidelines, as well as determine and review which tests should be made on the estuary to make sure it is running to the fullest and healthiest. Monitoring the Salmon Stock Our management plan is maintained by having reports on how many fish are successfully making it back to the river by using ADF&G aerial surveys on this pink salmon index stream. If our researchers feel that enough salmon have escaped, then they will open the fisheries. The fish will be counted over a period of three months: June, July, and August. If these guidelines are followed, the pink salmon estuary will be healthy and the fish will not be overfished. Escapement Fixed escapement is a harvest policy that makes sure that sufficient numbers of adult spawning salmon escape capture in the fishery and are allowed to spawn in the rivers, thus maintaining the long term health of the stocks. However, when the salmon managers

10 Mateer-Olson et. al 10 open and close fisheries on a daily basis and allow too many salmon to be caught in a single run, they alter the genetics of these salmon, which may in turn, alter the spawning populations as a whole. When run failures occur, managers close fisheries but this does not always prevent the salmon from changes in their genetic make up. Pink salmon have special behaviors that make them especially vulnerable to fishing pressure. Salmon exhibit high natural population variability that is driven by broad scale environmental change. If the salmon do not have too much pressure, then the salmon will be able to be properly sustained and yield a successful harvest (Kudish, 2012). User Groups Gill Net Fishery Gill netting involves laying a net wall in the water path of the fish and waiting for the salmon to put its head in the mesh. When this occurs, the gills get entangled in the webbing and the fish is prevented from escaping. Most gillnetters are small one or two man boats (ASMI, 2012). The Department of Fish and Game tightly regulates all commercial fishing openings in Alaska. They allow gillnetters to fish anywhere from zero to seven days a week depending on region, number of fish caught, strength of salmon run, etc. The duration of an opening is usually either 12 or 24 hours. Between openings, fishermen make repairs, prepare for the next opening, and rest (ADF&G, 2012). Purse Seine Fishery A purse seine is a net, which is set in a circle and can be drawn closed at the bottom. Salmon tend to jump on the surface of the water, which gives away the school s location as it moves through the water. When not actually engaged in setting or retrieving the net, every person on a purse is watching the water for a sign of fish (ASMI, 2012).

11 Mateer-Olson et. al 11 The purse seine fisheries management plan for Southeast Alaska was started in 1991, and was based on the 1991 pre season pink salmon forecast, as well as historical escapement and fishery performance. The purse seine fishery normally accounts for about 70 90% of the total commercial salmon harvest in the Southeast Alaska region, with pink salmon being the primary species targeted by the seine fleet. The purse seine fishery is managed on the abundance of pink salmon stocks. Adult tagging studies demonstrate that pink salmon stocks in Southeast Alaska exhibit a distinct separation between the northern and southern parts of the region. Generally, management of the purse seine fishery is by district. Districts 1 through 8 are grouped together as southern Southeast, and Districts 9 through 14 are known as northern Southeast (ADF&G, 1991). The primary management goals for the Southeast Alaska purse seine fishery are to obtain the overall pink and chum salmon spawning escapement goals with the best possible distribution to all systems. The management plan states that there is a goal of providing an orderly fishery while harvesting those fish in excess of spawning escapement methods and still minimize, to the extent possible, the interceptions of salmon destined for those fishing districts where weak returns are expected. We believe that the Purse Seine fishery picked these goals because, as stated, This will promote a harvest of good quality fish within constraints dictated by run size and timing, manage the District 4 purse seine fishery consistent with the provisions of the United States/Canada Pacific Salmon Treaty, and manage for a catch of Chinook salmon (28 inches or larger) that fall into the yearly amount allowable by the salmon treaty (ADF&G, 1991).

12 Mateer-Olson et. al 12 Threats To properly preserve pink salmon in Carroll Inlet we must look at the factors that threaten pink salmon. We chose what we think are the top three threats: overfishing, ocean acidification, and change in physical factors: mainly salinity, ph, dissolved oxygen content, water quality, and temperature. Overfishing: One of the major threats to all salmon is overfishing. We will use the term overfishing here to describe a situation where fish are being caught at a rate that exceeds the rate at which species reproduce. Overfishing can cause many different problems but what our group considers to be of high importance two particular factors. The first is the potential change in the genetics in future generations of salmon and the second is overfishing the stock past the point of recovery (WBGH, 2001; Nuttall, 2012). Through overfishing, humans create a sort of selective pressure (WBGH, 2001). An example of this would be the current size of pink salmon. According to our research, the average size of pink salmon that return to the stream have decreased nearly 30 percent in the last 40 years (WBGH, 2001). A plausible explanation for this decrease is that the salmon that remain, after you fish all the larger salmon, are all small enough to pass through the holes in fishers nets. The salmon then breed with the other small salmon, and we end up with smaller sized salmon offspring. Humans adjust to this new size, and once more, all the small salmon are left. The cycle then repeats itself, until eventually, the salmon might grow too small to be of any real use to us as a harvest. As we mentioned earlier, another reason overfishing is a danger to pink salmon is because it could one day deplete our pink salmon stock past recovery. While this may not

13 Mateer-Olson et. al 13 seem likely now with the abundant pink salmon resource available, overfishing past the point of recovery has happened before with other types of fish. Back in 1993 in Eastern Canada there was a collapse of cod populations that was so bad that a moratorium was declared on the fishing of that species (Myers, Hutchings & Barrowman, 1995). Ocean Acidification: Ocean acidification is the decrease in the ph of Earth s oceans, caused by absorbing carbon dioxide, or CO2, from the atmosphere. Ongoing acidification of the oceans can poses a threat to the food chains connected with the oceans in general and the salmon specifically by impacting organisms that the salmon eat (PMEL, 2012). Our group would monitor the ph of the estuary to check for trends in changing acidity. Funding the Plan After examining the different options, our group decided that the best way to fund this management plan would be through the self tax of the user groups. This option seemed the most reliable and fair to us compared to other options, especially when compared to things such as using the money gained from selling permits, which would prove harmful to the group if sales do not go as planned. It is also better than the option of using taxes from groups such as tourists, because if something bad were to happen, like the death that happened in Ketchikan when a tourist got ran over by a Duck Tour bus, it could make business drop, and would decrease the funds. With these points in mind, self funding would be the most justifiable, especially since that with self tax, the funds would come from a reliable source. With self taxing, the Carroll Inlet Pink Salmon Preservation Committee could hold a forum on how much each user group is willing to pay and then work out a compromise among themselves. The

14 Mateer-Olson et. al 14 committee, which includes members from each of the user groups, mentioned previously, would decide how much they would need to pay to keep their fishery working and maintain the health of the estuary. Funding Regulations: If any individual user group does not pay their fees they will be fined twice the amount they were originally supposed to pay. This way they can make up for the money lost in the non transaction. Fees will be paid to the committee at the end of each pink salmon fishing season, as well as a minimal fee before a pink salmon fishing season to pay for the workers collecting the taxing fees. If the pink salmon are fished past their guidelines, there will be an extra fee and a revocation of the fisher s CIPSPC fishing permit. The permit will be returned in two years if the fisher has paid all fees as well as the extra penalty fees. If a fisher ever violates federal or state regulations, their CIPSPC fishing permit will be revoked and they must pay an additional penalty fee. Subsequently, they will never be able to acquire a permit again. Snohomish Estuary As a comparison estuary we chose the Snohomish estuary, which is located at the shoreline of Puget Sound, off the coast of Washington state. It is 19.5 square miles, 9 miles in length and anywhere from 3 to 4 miles wide, depending on rainfall. Most of the water flowing into Snohomish River comes from rainwater and snowmelt. Although Snohomish Estuary is different in geographical terms from Carroll Inlet, they are both home to a large diversity of wildlife that depend upon the estuary. (Roberts, 1997).

15 Mateer-Olson et. al 15 The Snohomish area supports a wide range of wildlife, including more than 350 types of birds, a large variety of plants, sea mammals and salmon fry (Snohomish River Estuary). While most rivers in the Washington area have only odd year returns, Snohomish River is the only river in the Washington area to facilitate pink salmon yearly (NOAA, 1993). Ecology of Snohomish River and Estuary The entire salmonid migration for Snohomish River happens all year round, but tends to be more frequent from August to March. Pink salmon migrate upstream during the months of August and September. After emerging from the gravel around March or April, and sometimes as late as May, pink salmon fry begin to migrate downstream. The salmon fry in Snohomish River use near shore areas for early growth (NOAA NWFSC, 2012). Odd behavior has been observed in the migration of pink salmon in Snohomish estuary. They have been observed spending their entire marine phase in the near shore environment. The first study conducted on these salmon was in 1955 and were identified by their relatively small size. This small size can also be observed in our Carroll Inlet example mentioned above, as well (NOAA NWFSC). It is unknown whether these year round salmonid residents have an effect on the herring of the area, but the return rate of herring to the rivers is relatively low at 30% 50% returning annually ("Pacific herring information," 2012).

16 Mateer-Olson et. al 16 Human Interaction Washington estuaries are affected more by human interaction than those in Southeast Alaska. While most estuaries in Alaska are remote and mostly accessed exclusively by fishing vessels, Washington s growing population has brought people closer and closer to the waters edge, affecting the waterway. Snohomish is a prime example of this because over the years companies have set up industrial plants around the river, leaving negative effects on the river and the aquatic life of the area. Management Plan for Snohomish Snohomish estuary is quite different than Carroll Inlet, but we believe that the plan we have created for Carroll Inlet could be effective for Snohomish as well. The salmon industry in Snohomish basically consists of the same fisheries. The monitoring system described in our management plan can be done using Washington Department of Fish and Wildlife. Our plan is versatile, as it covers the main threats to pink salmon throughout its habitat range. Conclusion In our research we found that, in the past, there has been low salmon population numbers due to overfishing. When overfishing occurs, the genetic make up of the salmon stock can be altered. Another area that could be affected by the low pink salmon numbers is all of the predator prey relationships that involve pink salmon. In order for the pink salmon in Carroll Inlet to maintain their health, we recommend limits to fishing and scientific monitoring of the estuary funded by a committee s self tax. If this management

17 Mateer-Olson et. al 17 plan is enforced, it can help keep the Carroll Inlet estuary healthy as well as preserving the commercial fishing business, which also helps all of the businesses that depend on the fishery. In addition, charter fisherman, sports fisherman, and people who use these fish for subsistence will benefit.

18 Mateer-Olson et. al 18 Figures and Graphs Figure 1: Overview of Puget Sound including Location of Snohomish River (NOAA, 1958). Chart 3: This Chart shows the average exvessel prices of salmon from Courtesy of Gunnar Knapp.

19 Mateer-Olson et. al 19 Chart 1: This Chart shows the number of Pink Salmon that were commercially caught annually since Courtesy of ADF&G. Chart 2: This chart shows the amount of salmon in weight caught commercially since Courtesy of Gunnar Knapp References AFSC. (2012, November 03). ema: Forecasting pink salmon harvest in Southeast Alaska. Retrieved from Alaska Department of Fish and Game. (1991, June). Retrieved from Alaska Department of Fish and Game (2011, October 31) Alaska commercial salmon harvest. Retrieved from Alaska Department of Fish and Game. (2012, November 11). Pink salmon (Oncorhynchus gorbuscha). Retrieved from Alaska Department of Fish and Game. (2012, August 13). Fp Retrieved from 18.pdf

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22 Mateer-Olson et. al 22 NOAA. (25, March 2008). Why are estuaries important? The economy and environment. Retrieved from Nuttall, N. (2012). Retrieved from United Nations website: Oberrecht, K. (n.d.). Salmon in the estuary. Retrieved from Orth, D. J. (1967). Geological survey professional paper. Washington D.C., Maryland: United States Government Printing Office. DOI: books.google.com/books?id=agqaqaaiaaj&printsec=frontcover Pink salmon facts. (1996, December 16). Retrieved from PMEL. (2012). Ocean acidification. Retrieved from Acidification Research Group Corvallis. (2009). Wild salmon center. In Wild Salmon Center. Retrieved from Roberts, P. Environmental Protection Agency, Puget Sound Water Quality Authority, Washington State Department of Ecology. (1997). Snohomish estuary wetlands integration plan. Retrieved from Department of Planning and Community Development website: pdf Snohomish river watershed draft initial assessment. (1995, May). Retrieved from Washington Department of Fish & Wildlife, (2012).Pacific herring information summary. Retrieved from website: WBGH Educational Foundation & Clear Blue Sky Productions, Inc. (2001). Shrinking salmon. Retrieved from