98 species. Moreover, due to changing stream variables and changes in plankton bloom as ice melt is accelerating, misbalance of this equilibrium may have long-term impacts for salmon populations, including lack of nutrient availability decreasing size of the fish, in turn hindering survival (Johnson, 2016). Although for some species the consequences of range extension and fluctuation in biomass are not entirely known, the same cannot be said for Alaskan pollock and crab. Pollock and crab are two primary economic driving fisheries in the state, and climate change already is hindering those catches, with problems expected to accelerate. Alaskan pollock is the largest fishery in the US. Annual catches average upwards of 1.5 million metric tons, a first wholesale value of nearly $1.5B in 2017 and 2018 (McDowell Group, 2020). However, with more persistent periods of warmer water in the Bering Sea, prosperity for pollock may be challenged. Current warming projections are expected to lead to a drastic decline in Alaskan pollock fisheries: an estimated 32%–58% lower pollock harvest by 2050. Research suggests that while initial periods of warmer waters reduce pollock mortality rates and enhance growth, subsequent reduction in high-quality prey and increased predation of juvenile pollock result in a lower rate of survival to adulthood (Mueter et al., 2011). During warmer periods, there is less availability of lipid-rich plankton and krill, which typically become more available following melt of abundant ice; after low-fat summer diets, young pollock are not well suited to survive winter. The low-lipid-content plankton dominant in warm periods do not provide sufficient nutrients (Alaska Fisheries Science Center, 2015). Additionally, in those warm periods, the metabolism of predator fish increases where predators prey more heavily on juvenile pollock. These relationships explain the shifts in pollock populations moving further north to remain in cold water, allowing them to better survive. It is estimated that eventually 35% of US pollock biomass will have migrated across the Russian maritime border, making the fish inaccessible to the Alaskan fleet (Johnson, 2016). For Alaskan crab fisheries, warming water and ocean acidification threaten to hasten an already noticeable prolonged decline in stocks of various crab species. Bering Sea crab fisheries are some of the most economically important fisheries in the US, contributing an annual average of $238M in first wholesale value in 2017 and 2018 (McDowell Group, 2020). This economic benefit is in jeopardy because complete cessation of king crab fishing is estimated to occur before 2100 due to dwindling biomass (Johnson, 2016). King crab and snow crab have been found particularly susceptible to ocean acidification during the larvae stage of development, when reduced calcium ion concentration limits their ability to form shells. Another concern for both snow crab and tanner crab, the parasitic dinoflagellate Hematodinium, causes a potentially fatal disease known as bitter crab syndrome in both species. This disease is believed to be connected to climate change, although no direct link has been proven beyond correlation (Alaska Fisheries Science Center, 2021). Crab fisheries stakeholders have already felt the effects. Snow crab populations in 2021 fell 55% compared to 2019, and decreased red king crab populations resulted in temporary closure of the Bristol Bay fishery for the first time since 1994. According to the trade group Alaska Bering Sea Crabbers, these two factors cost the industry in excess of $100M for the 2021 season (Welch, 2021a). In short, the harm to the Alaskan pollock and crab industries demonstrates the likely growing risks of climate change for other segments of what currently is a robust industry in the state. Adaptive Management: A Necessary Response to Climate Change Fishery management encompasses the practices and regulations set to achieve sustainable biological, social, and economic value with respect to limited aquatic resources. Furthermore, general fishery management agencies can be broken down into two categories: management councils and analytic research organizations. Referring to the former, councils typically are responsible for setting catch limits, developing and implementing management plans, and developing research priorities for a given region. Due to an interconnected relationship, the councils work closely with analytic research organizations that provide insight and conduct research studies so that optimal management decisions can be made. For Alaskan fisheries, the management
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