In 2001, white abalone, Haliotis sorensoni, became the first marine invertebrate to be listed as an endangered species. A submarine survey of rocky reefs for white abalone at offshore islands and banks in southern California found white abalone at densities three orders of magnitude (ie., 1000 times) lower than historically reported. Using the abundance of abalone at different locations and the amount of potentially suitable habitat at these locations, the investigators conservatively estimated that 3,000 individuals (or < 2.3 metric tons) remain in California (most on the offshore banks) compared with the total combined commercial landing of >280 metric tons. An estimate of the number of white abalone in Mexico (based on rough estimates of suitable habitat) only added another 200-2,000 animals to the total abundance for the species. Abalone were associated with Laminaria farlowii (an alga) and occurred on relatively large rocks (with a variety of algal/invertebrate cover), usually near the rock-sand interface. The investigators were able to collect several white abalone and hold them in captivity until they were ready to spawn. Spawning resulted in settled juveniles that are presently under culture.