Sea otter foraging along Monterey Bay beaches and at Atascadero State Beach has precluded recreational Pismo clam fisheries at six major clamming beaches. Outside the sea otter's foraging range Pismo clam stocks are yielding good catches; apparently the stringent controls on the recreational fishery is adequate to maintain the State's Pismo clam stocks. Clammer interviews at Orange and Los Angeles County beaches and at beaches near Pismo Beach and Morro Bay and in Monterey Bay revealed the clam stocks to be on a healthy, sustainable yield basis. Exceptionally
large numbers of small 1.5 to 3.5 inch Pismo clams were reported at all clam beaches surveyed north of Pt. Conception indicating good year class survival in recent years. Sea otters forage dense Pismo clam beds by moving along a "front", progressively foraging from one beach to the next, reducing the clams to low levels before moving on. Some sea otters continue to forage throughout the areas previously depleted by the larger aggregate moving northward, thus the large numbers of sublegal clams
in the 1.5 to 3.5 inch size group in these intertidal and shallow subtidal areas are not expected to reach legal size in numbers sufficient to develop a recreational fishery. In Monterey Bay about 60,000 Pismo clams were removed or killed by human activity in the April 1974 to March 1975 period. A rough estimate of the Pismo clams consumed by sea otters during this same period in Monterey Bay is over 500,000 clams. (51pp.
