In the tide pools of La Jolla, where the Pacific Ocean breathes in and out over ancient volcanic rock, something remarkable is happening this summer. More than 50 of the world's leading marine taxonomists have descended on San Diego's coast—not for medals, but for something far more consequential: building a genetic map of life itself.

This two-week bioblitz, which began June 21 at the tide pools near Scripps Institution of Oceanography, marks the launch of the California Intertidal Biodiversity DNA Barcode Library Project. The initiative, led by the Southern California Coastal Water Research Project Authority with support from the California Ocean Protection Council, aims to create the most comprehensive survey of intertidal species in California's history—and fill a critical gap that has long hindered ocean conservation.

These coastal zones, where the ocean meets the land between the tides, are among California's most biologically rich and climate-vulnerable ecosystems. Rising ocean temperatures and sea-level rise are remaking them faster than scientists can track. Traditional monitoring methods often miss species entirely, but environmental DNA (eDNA) monitoring—matching genetic traces found in seawater to reference libraries—could change that. There's just one problem: those genetic databases remain dangerously incomplete along much of the California coast.

"These bioblitzes will briefly bring together one of the world's highest concentrations of marine taxonomists, and the catalog we produce will serve as a model for DNA reference libraries far beyond California," said Greg Rouse, curator of the Benthic Invertebrate Collection at Scripps Oceanography and one of the project's leaders. "It will set a baseline for tracking previously undocumented species and help inform the management decisions needed to protect these intertidal ecosystems."

Through July 4, teams will survey 23 intertidal sites stretching from Imperial Beach to Oceanside, investigating sandy beaches, estuaries, rocky shores, and even harbors teeming with encrusting organisms. Researchers collect specimens, photograph them using standardized methods, and preserve tissue samples for long-term archives. Most specimens undergo DNA barcoding—a process generating a unique genetic identifier for each species—while selected representatives receive full genome sequencing.

"Every sample will be tracked, cataloged and preserved—now and for the future," said Dean Pentcheff of the Natural History Museum of Los Angeles County. Specimens will be archived at major institutions including Scripps, the Natural History Museum of Los Angeles County, the California Academy of Sciences, and the UC Berkeley Herbarium, ensuring future generations of researchers can build on this work.

The project transforms fleeting observations into enduring knowledge—giving California a genetic baseline against which its changing coast can finally be measured.