Ocean and Ecosystem Observations on the Trinidad Head Line

A project of the Southwest Fisheries Science Center’s Cooperative Fisheries Oceanography Research Team.

Since late 2007, the Southwest Fisheries Science Center (SWFSC) and Humboldt State University (HSU) have conducted frequent ocean observing cruises to characterize seasonal and interannual variability in the plankton ecosystem in coastal waters off northern California.

On these cruises, we collect data and samples at five stations along the Trinidad Head Line, a transect that extends from the inner continental shelf to the middle of the continental slope due west of the HSU Marine Laboratory in Trinidad, California. At each station, we:

• Measure physical, chemical, and biological parameters (e.g., temperature, salinity, chlorophyll fluorescence, pH, dissolved oxygen) throughout the water column (to a maximum depth of 500 meters)
• Collect water samples at various depths for laboratory assays that measure concentrations of chlorophyll, nutrients, and harmful algal bloom toxins (domoic acid)
• Collect zooplankton samples from the upper 100 meters of the water column that are later analyzed to produce data on community structure in krill, copepods, and larval fish, and on variability in size structure of dominant krill species

These data are further complemented by:

• Observations at a Trinidad Wharf shore station maintained by HSU and the Central and Northern California Ocean Observing System (CenCOOS)
• An autonomous glider that extends the Trinidad Head Line several hundred kilometers offshore, a collaboration between Oregon State University, CeNCOOS, the Northwest Association of Networked Ocean Observing Systems (NANOOS), HSU, and the SWFSC

In combination, these data give insight into how coastal ecosystems respond to seasonal cycles and larger scale climate dynamics, and contribute to a much broader coastwide collaborative effort to understand the dynamics of the California Current Large Marine Ecosystem.

More Information

• SWFSC Cooperative Fisheries Oceanography Research Team
• Humboldt State University Marine Laboratory
• CenCOOS
• NANOOS

Selected Publications

Robertson, Roxanne R., and Eric P. Bjorkstedt. 2020. Climate-driven variability in Euphausia pacifica size distributions off northern California. Progress in Oceanography 188:102412.
https://doi.org/10.1016/j.pocean.2020.102412

Thompson, Andrew R., et al. 2019. State of the California Current 2018-2019: A novel anchovy regime and a new marine heat wave? CalCOFI Reports 60:1-65.
https://calcofi.org/publications/calcofireports/v60/Vol60-SOTC2019.pdf

Harvey, Chris, et al. 2019. Ecosystem status report of the California Current for 2019: A summary of ecosystem indicators compiled by the California Current Integrated Ecosystem Assessment Team (CCIEA). NOAA Technical Memorandum NMFS-NWFSC-149. 87 p.
https://doi.org/10.25923/p0ed-ke21

Jones, Timothy, et al. 2018. Massive mortality of a planktivorous seabird in response to a marine heatwave. Geophysical Research Letters 45(7):3193-3202.
https://doi.org/10.1002/2017GL076164

Bjorkstedt, Eric P., and William T. Peterson. 2015. Zooplankton data from high-frequency coastal transects: Enriching the contributions of ocean observing systems to ecosystem-based management in the northern California Current. In: Yonggang Liu, Heather Kerkering, and Robert H. Weisberg (eds.), Coastal ocean observing systems, p. 119-142. Academic Press (Elsevier).
https://doi.org/10.1016/B978-0-12-802022-7.00008-0