Potential Impacts of a Commercial Hatchery on Kachemak Bay
Find out about the Costs to Wild Fishes
Background
Tutka Bay Hatchery releases approximately 60.6 million pink salmon fry into Kachemak Bay every year. Kachemak Bay is both a Critical Habitat Area and a State Park. Once known as the “richest bay in the world,” it has experienced the loss of significant stocks of Dungess, tanner and king crab, five species of shrimp, wild salmon and herring; halibut quotas for sport fishermen in 2020 are slated to be reduced by 40%.
When the Tutka Bay hatchery first started operations, like hatcheries all over the State of Alaska, it was meant to rehabilitate depressed stocks. Because hatcheries were new, release sizes, stock sources, and operation sites were experimental. At the outset, Tutka Bay hatchery’s releases were relatively similar to the sizes of the natural run. Stream surveys that took place three years before estimate wild returns of 14,500 fish to Tutka Lagoon Creek; hatchery returns remained in that range until the early 90s. However, the release of an average of 60.6 million fish every year between 1995 and 2017 represents a shift in purpose and scope of impact from the initial intent of rehabilitation. Escapement numbers at Tutka Lagoon Creek are variable, but in some years can be 10 times more than the suggested escapement goals of 6,500-17,000 fish. With this basic information in mind, it is clear that operations may exceed the carrying capacity of the waters of Kachemak Bay. In this respect, Tutka Bay is not unique; hatchery fish in Alaska are seldom released in numbers that are related to the carrying capacity of the receiving stream.
Do Alaskans Benefit?
The Tutka Bay hatchery has not been a benefit to many people, though it has been a significant benefit to a few. By far the largest beneficiary of the Tutka Bay Hatchery is Cook Inlet Aquaculture Association. Between 1996 and 2017, the hatchery harvested 82% of the total pink salmon harvest, and commercial common property harvesters captured 18% of the total.
The significant losses to lodges, guides and other seekers of a scenic experience have been clearly established in the public record. There are hundreds of businesses around Homer who make their living from sharing the scenic bay with visitors. Their interests are aligned with the guiding statutes of the scenic park.
The potential losses to biodiversity and the associated scenic value as well as to sport and subsistence fishermen are outlined below.
Competition, Predation, and Straying
The Tutka Bay Hatchery pink salmon releases that are orders of magnitude larger than historic wild salmon in the bay very likely reduce areas available for public enjoyment by reducing fitness and productivity of species that are important sources of recreation including King, Tanner and Dungeness crab, halibut, shrimp, herring, Pacific cod, clams, and muscles, which juvenile pink salmon are known to either compete with or predate upon these species. Pink salmon are known to stay in Kachemak Bay throughout the summer, so the scope of potential impacts are highly significant.
Furthermore, hatchery fish are not as fit as wild fish, and recent ADFG studies show that hatchery pink salmon progeny have about 50% less likely to survive than wild progeny. When hatchery fish mate with wild fish there are significant losses to genetic variation in the total population and also significant losses to the fitness of the wild population. See the following for a discussion of hatchery straying and impacts to wild salmon genetic diversity and fitness:
- https://www.adfg.alaska.gov/static/fishing/PDFs/hatcheries/research/2016_nprb_final_report.pdf
- https://www.adfg.alaska.gov/static/fishing/PDFs/research/genetics_finfish_policy.pdf
- https://link.springer.com/article/10.1007/s10641-012-9975-7
- http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0081916
- https://www.researchgate.net/publication/5909528_An_Evaluation_of_the_Effects_of_Conservation_and_Fishery_Enhancement_Hatcheries_on_Wild_Populations_of_Salmon1
Assessment of the scope of impacts of straying, competition, and predation of hatchery operation to the flora and fauna of to wild populations in Kachemak Bay would have to begin with the following questions:
- Where do hatchery juvenile and adult salmon go in Kachemak Bay?
- How long are hatchery juvenile salmon and returning adults in Kachemak Bay?
- What are they eating in the nearshore environment?
- How much are they eating in the nearshore environment?
- How does the volume and quality of the hatchery salmon diet affect the flora, fauna of the Kachemak Bay State Park and Critical Habitat Area?
- What is the carrying capacity of the waters of the state park where the hatchery fry and adults are found?
None of these questions has been studied by ADF&G.
Discharges into Alaskan Waters
Hypernutrification due to salmon farming is problematic in fjords and basins, like Tutka Bay, because they tend to be characterized by low flushing rates and therefore may be sensitive to organic waste loadings. Hypernutrification leads to anoxic conditions that basically smother all life at the bottom of the basin, which include crab, shrimp and other shellfish.
A primary contamination concern related to aquaculture involves the organic wastes produced by salmon hatcheries. Types of waste include excess feed, fish feces and urine, fish carcasses and biofouling. A recent pilot study conducted in British Columbia found that commercial feed used in salmon hatcheries had significant concentrations of PCBs, organchlorine pesticides, brominated diphenyl ethers, PAHs and mercury. Persistent contaminants in fish food are of concern since these chemicals are known to bioaccumulate. Health officials say PCBs pose a danger even in tiny amounts: in addition to causing cancer, PCBs can affect brain development and mimic the hormone estrogen. The State of Washington has enacted a law requiring state agencies to purchase PCB-free products or the best alternative.
In 2017, Cook Inlet Aquaculture “disposed” of 267,913 dead fish (868,038 lbs.) in Tutka Bay, after removing their row to hatch the next year’s brood stock. DEC currently permits discharges from the Tutka Bay Lagoon Hatchery under an Alaska Pollutant Discharge Elimination System General Permit to Aquaculture Facilities in Alaska, Permit No. AKG130000. This permit only requires that receiving waters be sampled by operators once a year, at a time and location chosen by the operator. Receiving waters at the site of the carcass dump are not required to be monitored. No data is being collected on what the Clean Water Act, section 117 calls the living resources of the site: “grasses, benthos, phytoplankton, zooplankton, fish, and shellfish” except immediately below the pens. There are no random visitations on the part of DEC to verify accurate reporting.
Moreover, there is the highly significant problem that, according to DEC Seafood Processing Lead Clynda Case and Jackie Ebert, Environmental Specialist IV there is no historical record of any reporting from Tutka Bay Hatchery to DEC on effluent discharges, receiving water body quality, or the benthos below the net pens or in in the carcass dumping grounds, or on water flow at the net pens or at the carcass dumping site. Sadly, Tutka Bay is not alone; there is little to know reporting to DEC from any hatchery in the State of Alaska for the entire history of operation—over 40 years.