19  Central California Current Forage

Description The Central CCE forage survey (known as the Rockfish Recruitment and Ecosystem Assessment Survey, RREAS) samples much of the West Coast each May to mid-June, using midwater trawls sampling between 30 and 45 m depths during nighttime hours. The survey targets young-of-the-year (YOY) rockfish species and a variety of other YOY and adult forage species, market squid, adult krill, and gelatinous zooplankton. Juvenile rockfish, anchovy, krill, and market squid are among the most important prey for CCE predators (Szoboszlai et al. 2015). Time series presented here are from the “Core Area” of that survey, centered off Monterey Bay. Catch data were standardized by using a delta-GLM to estimate year effects while accounting for spatial and temporal covariates to yield relative abundance indices, shown with their approximate 95% confidence limits (Santora et al. 2021). This modeling approach was adopted in recent reports to reduce bias in 2020, when sampling effort and spatial coverage was severely constrained by the COVID-19 pandemic.

Pelagic forage data from the Central CCE were provided by J. Field, T. Rogers, K. Sakuma, and J. Santora, NMFS/SWFSC, from the SWFSC Rockfish Recruitment and Ecosystem Assessment Survey (https://go.usa.gov/xGMfR). Similarity analysis and cluster plot by A. Thompson, NMFS/SWFSC.

Indicators

• Species:
  • Aurelia
  • Chrysaora
  • Adult Anchovy
  • Adult Sardine
  • Total Krill
  • Market Squid
  • Total Myctophids
  • Octopus
  • Pyrosomes
  • Salps
  • Thetys
  • YOY Anchovy
  • YOY Pacific Hake
  • YOY Rockfish
  • YOY Sanddabs
  • YOY Sardine
• Component Category: Ecological Integrity
• CCIEA Data Contact: john.field@noaa.gov
• Institution: NOAA SWFSC
• Source Data: Dr. John Field (NOAA; john.field@noaa.gov) and Tanya Rogers (NOAA; tanya.rogers@noaa.gov) from the SWFSC Rockfish Recruitment and Ecosystem Assessment Survey (RREAS; https://storymaps.arcgis.com/collections/af0fa37db2bf4f1cadb024ec0ffbdfb5).
• Additional Calculations: Samples represent catch (individuals) per standard 15 minute trawl (CPUE) from the historical core area (36.5-38.2N) of the RREAS during late spring (May to mid-June). Data are log(CPUE+1) transformed, with geometric means calculated on non-zero data. Note: Sampling effort was greatly reduced in time and space during 2020 due to COVID restrictions, and associated data reflected substantial bias for many taxa. Catches were standardized by using a Bayesian delta-GLM to estimate year effects while accounting for spatial and temporal covariates, and to estimate approximate 95% confidence limits; see Santora et al. 2021 (https://doi.org/10.1038/s41467-021-26484-5) for model approaches used to develop alternative indices in 2020.

Indicator Download

ERDDAP™ link:

https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_EI_FBC.html

References

Santora, Jarrod A, Tanya L Rogers, Megan A Cimino, Keith M Sakuma, Keith D Hanson, EJ Dick, Jaime Jahncke, Pete Warzybok, and John C Field. 2021. “Diverse integrated ecosystem approach overcomes pandemic-related fisheries monitoring challenges.” Nature Communications 12 (1): 1–10.

Szoboszlai, Amber I, Julie A Thayer, Spencer A Wood, William J Sydeman, and Laura E Koehn. 2015. “Forage species in predator diets: synthesis of data from the California Current.” Ecological Informatics 29: 45–56.