Certainly they have dwindled from what they once were. Red, black, and white abalone are three of the species that live along California's coast; red abalone is the only type that's currently fishable, recreationally rather than commercially and with strict rules. In 1996, the numbers of black abalone appeared to have been reduced to a fifth of their original levels in some places; the IUCN still lists the population as in decline. 99% of the white abalone population in Southern California has disappeared between the 1970s and the present.