Skip to Main Content

Breadcrumb

GOA_Noteworthy

Noteworthy: Gulf of Alaska 2024

We include information here that is relevant to ecosystem considerations of fisheries managers, but does not fit our typical indicator format. Information included here is often new, a one-time event, or a deeper discussion on a topic of interest

Endangered Species Act and Critical Habitat Petition Updates

Contributed by Julie Scheurer and Jenna Malek, Protected Resources Division, Alaska Region NOAA Fisheries Contact: julie.scheurer@noaa.gov (North Pacific Right Whale Critical Habitat Update) and jenna.malek@noaa.gov (Gulf of Alaska Chinook Salmon)

North Pacific Right Whale Critical Habitat Update: The Center for Biological Diversity and Save the North Pacific Right Whale submitted a petition to the Department of Commerce to review the areas designated as critical habitat for the North Pacific right whale. NOAA Fisheries, Alaska Regional Office is leading the response to the petition and published a positive 90-day finding in July 2022 that a revision to critical habitat may be warranted. In September 2023, NMFS released a 12-month finding on a petition to revise North Pacific right whale critical habitat. NOAA found that the petitioned action was warranted and have been taking the following steps to identify areas that meet the definition of critical habitat under the ESA:

  1. Analyzing all available acoustic data collected in areas recommended by the petitioners and currently designated as critical habitat
  2. Assessing spatial and temporal patterns of prey species (i.e., copepods and euphausiids) in conjunction with oceanographic information
  3. Analyzing sightings data for evidence of feeding behavior
  4. Synthesizing available acoustics data, trends in zooplankton, and sightings data to identify critical habitat areas
  5. Conducting and impacts analysis
  6. Developing a proposed rule for public comment

As of October 2024, NOAA is still in the analysis process and have begun the impacts analysis.

Gulf of Alaska Chinook Salmon Status Review under the Endangered Species Act: On January 11, 2024, NMFS received a petition from the Wild Fish Conservancy to delineate and list one or more evolutionarily significant units (ESUs) of Chinook salmon Oncorhynchus tshawytscha in the Gulf of Alaska (GOA) as threatened or endangered under the Endangered Species Act, and to designate critical habitat concurrently with the listing. On May 24, 2024, NMFS announced a positive 90-day finding on the petition and commenced a status review of the species to determine whether one or more ESU warrants listing (89 FR 45815).

NMFS has convened a team of federal scientists led by the AFSC to collect and analyze the best available scientific and commercial information on the species, including its biology, ecology, abundance and population trends, and threats to the species, in order to evaluate the species’ current status and extinction risk. The status review team will develop a peer-reviewed status review report to inform the agency’s determination as to whether the petitioned action is warranted.

Within one year of receipt of the petition, NMFS must complete the status review and make a 12-month finding. If, after completing the status review and considering ongoing conservation efforts, NMFS determines that listing is not warranted, a negative 12-month finding will be published in the Federal Register and no further action is taken. Alternatively, if NMFS determines that a listing is warranted, we will publish a positive 12-month finding and proposed rule in the Federal Register and seek public comments on the proposed listing. The status review report, 12-month finding, and proposed rule (if applicable) for GOA Chinook salmon are expected to be completed in early 20255.

5For updates: https://www.fisheries.noaa.gov/action/petition-list-gulf-alaska-chinook-salmonthreatened-or-endangered-under-endangered-species

Low Returns of Pink Salmon in 2024

Contributed by Bridget Ferriss, Alaska Fisheries Science Center, NOAA Fisheries Contact: bridget.ferriss@noaa.gov

Pink salmon returns in the Gulf of Alaska, in 2024, were low relative to usual lower even-year returns, and lower than forecasted (with the exception of southeast AK) (Whitehouse in this Report, p.113, Vulstek et al. in this Report, p.124, Strasburger et al. in this Report, p.116). Pink salmon survival can be influenced by freshwater conditions, early marine survival in the coastal, shelf environment, and adult survival in the oceanic environment in the GOA gyre. The salmon spend one year in the ocean environment before returning to spawn, influenced by previous year shelf and open ocean conditions (e.g., temperature and prey availability). Here we review potential explanations of the low returns in 2024.

There is some evidence that both the nearshore environment and oceanic environment may have contributed to the low pink salmon returns in 2024. Given the low returns of pink salmon affected both wild and hatchery populations, it appears freshwater conditions were not the driving reason behind the low survival. Yasumiishi (2023) summarized how the 2023 early marine environmental conditions for southeast AK juvenile pink salmon were generally less favorable for growth and survival, including lower body condition, low abundance, and shorter fish (Fergusson and Strasburger, 2023). Primary and secondary (zooplankton) production was variable but below average in parts of the GOA, indicating a reduced prey base for pink salmon, but not showing extreme reductions (Ferriss, 2023). The fact that southeast pink salmon AK forecasts were more accurate than other GOA regions, supports some evidence of early marine mortality. Southeast AK forecasts are based on juvenile salmon surveys (integrating some measures of early mortality) whereas other GOA regions’ forecasts are derived from adult returns or harvest in the previous brood year (2 years prior), which doesn’t integrate any components of early marine mortality for the current year adult returns.

Ruggerone (2024) describes the potential for the near record high abundance of pink salmon in 2023 may have contributed to the low returns in 2024, due to increased competition where they overlap in the GOA oceanic environment (off the shelf). There are few monitoring data to validate the potential for limited prey conditions in the GOA oceanic environment. Ostle and Batten (In this Report, p.77) report below average mesozooplankton biomass and lower biomass of large copepods, relative to smaller copepods in 2023 in the oceanic environment, similar to conditions in 2020 – 2022.

Numerous studies link variation in marine species’ diets, condition, growth, and reproduction to competition with pink salmon for zooplankton, squid and forage fish (summarized in Ruggerone et al., 2023). While trophic cascades in marine systems are debated, the biennial pattern of pink salmon brood years (higher returns in odd years and lower in even years) allows for some correlative analyses. Batten et al. (2018) has suggested increased pink salmon can lead to reduced abundance of large copepods (increased grazing pressure) and increased large diatoms (reduced grazing pressure from copepods). Zooplankton-eating seabirds have shown indications of a reduced prey base in years of high pink salmon (higher competition) including reduced reproductive succeed (black-legged kittiwakes, Zador et al., 2013) and reduced condition (short-tailed shearwaters, Toge et al., 2011). Other salmon populations exhibit changes in diet and reduced condition that have been linked to pink salmon competition (Tadokoro et al., 1996; Ruggerone et al., 2003). Total pink salmon biomass (hatchery and natural origin) returning to the GOA in 2015 was approximately 403,566 mt (Ruggerone and Irvine, 2018). The odd year pink salmon abundance has been higher in 2021 and 2023. In comparison, the survey-estaimted biomass of dominant zooplankton predators in the groundfish community include Pacific ocean perch (NOAA bottom trawl survey estimate 1,595,547 mt in 2023) and walleye pollock (NOAA bottom trawl survey estimate 921,866 mt in 2023) (Callahan et al. in this Report, p.139. While pink salmon would have less of a predation impact than these groundfish populations, years of high returns of pink salmon and lower prey abundance could lead to increasde competition among these pelagic foragers. Conversely, years of low pink salmon returns (e.g., 2024) could experience reduced competition for zooplankton, squid, and forage fish prey.