Diablo Canyon power plant site ecological study Quarterly Report no. 15: January 1 - March 30, 1977

Abstract

Three permanent subtidal stations were surveyed. Little change in densities of quantified plants and animals was apparent at two of the stations. However, the density of giant red sea urchins, Strongylocentrotus franciscanus, declined 57 percent at station 15 in South Cove after foraging by about 20 sea otters, Enhydra lutris, occurred in February. Stormy seas hampered intertidal surveys. As a result, we were unable to conduct surveys at our Diablo Point study area. Survey dives were made to assess impacts of the cooling water flow immediately in front of the outfall structure. Our foam observations in Diablo Cove were discontinued after PG&E installed an automatic camera system on their Met Tower. The camera takes a photo every 15 minutes during daylight hours. A small raft of sea otters has taken up residence in a Macrocystis bed in the cove north of Diablo Cove. These otters are foraging at least as far south as Diablo Cove. (21pp.)