San Francisco Bay/Delta Estuary


A substantial component of CRAB’s work has focused on non-native species in the San Francisco Estuary, the most invaded estuary in the world.

Rapid Assessment Surveys

By organizing and implementing four surveys for non-native species in San Francisco Bay in 1993-1997, we developed a now widely-used Rapid Assessment (RA) survey approach for detecting and monitoring these species in marine waters. Similar surveys were later conducted, several of them with our help or under our leadership, in Washington, Oregon, southern California, New England, British Columbia, England, Panama and elsewhere; and a further survey was conducted in San Francisco Bay in 2004-2005, funded by the National Geographic Society.

Typically, an RA survey is conducted by a team of half-a-dozen to a dozen senior taxonomists and taxonomic specialists, along with a few field assistants, who initially sort and identify organisms in the field (focusing on fouling, intertidal or shallow subtidal organisms) and then transport them immediately to the laboratory for final identification and verification usually within 6-24 hours. The opportunity for taxonomist specialists to conduct or direct the collecting at the field site aided by initial identifications, and to examine fresh/live material in the lab, are a great help in meeting the challenge of distinguishing and then identifying novel organisms from undetermined source regions. These regionally synoptic surveys have contributed to our knowledge of the status of invasions, promoted broader understanding and awareness of invasions among scientists, policymakers and the public, developed a cadre of marine taxonomists who continue to work on invasions, and provided valuable field experience to students.