The distribution of fish eggs in the ocean provides valuable insights into the location and timing of fish spawning. Fish egg counts are also used to estimate spawning biomass, a key component of a commercial fishery’s stock assessment. The full value of egg and larvae surveys, however, is currently compromised by the fact that some species have eggs that are morphologically similar if not identical. This project has exploited an existing DNA barcoding database (mitochondrial DNA sequences) for West Coast fishes to develop oligonucleotide probes for 23 marine fish species. The probes target species whose eggs are abundant in California waters but are difficult to identify at the species level morphologically. In the coming year, scientists will use the probes (and others to be added to a bead array) to identify fish eggs in archived samples collected during CalCOFI and other cruises, in collaboration with NOAA Southwest Fisheries Science Center. The ultimate goal is to deploy an automated shipboard instrument for rapidly identifying species of fish eggs and larvae collected by nets and a continuous fish-egg sampler.