The Fisheries Resources Division uses a device known as the continuous underway fish egg sampler, or CUFES, to collect fish eggs while the ship is underway. Eggs captured by the CUFES are counted onboard the ship every thirty minutes or less. These data are normally transmitted to shore each day during the annual spring cruise. The Sardine Cruise page will be updated periodically during the cruise to illustrate the progress of the ship in assessing densities of Pacific-sardine, northern-anchovy, and jack mackerel eggs. Data from the CUFES along with other samples are used to assess the biomass of the sardine population in U.S. waters via the daily egg production method (Lo et al. 2004). Recent stock assessments for sardine can be downloaded from the Pacific Fishery Management Council.

Previous Spring Cruises

Egg maps from previous cruises are linked below. Each figure depicts the sampling pattern of the ship(s) as red lines, and number of sardine, anchovy, and jack mackerel eggs captured per cubic meter as vertical bars. The data are overlaid on an image of satellite-derived sea-surface temperature (degrees celsius) based on one-month mean temperatures near the middle of the sampling period (e.g., centered on 15 April). White areas indicate temperatures outside the range of 11-19 degrees or where no temperature data are available. Sea-surface temperature data were obtained from the NOAA CoastWatch website. They are from Pathfinder 5.5-km resolution measurements until 2008, and AVHRR 1.4-km resolution data thereafter.

Images in png format: