A biological sampling program at Jackson Point in Port Valdez, Alaska, was begun in December 1970. Sixteen artificial substrate samplers (8 multiplate and 8 rock-fllled baskets with net liners) were retrieved after 2 to 4 months' exposure. The most common groups in order of their abundance were Copepoda, Foraminifera, Nematoda, and Ostracoda during winter; Copepoda, Nematoda, Cirripedra, and Foraminifera, during spring; Pelecypoda, Amphipoda, Insecta, and Cirripedia during summer; and Pelecypoda, Copepoda, Insecta, and Nematoda during fall. The most abundant species collected during the study were the blue mussels (Mytilus edulis), copepods (Harpacticus sp.), midges (Clunio sp., Ghironomidae), and fairy shrimp (unidentified amphipods). During the summer and fall of 1972 the total number of epifaunal organisms was 22 times greater than during the same period in 1971, with Mytilus edulis comprising 88 percent of the community in 1972 (more than triple the percentage for 1971). The two sampler types collected approximately the same major groups of organisms; however, the multiplate samplers collected an average of 1.6 times more organisms than the basket samplers. The basket sampler, on the other hand, collected three more species per sample than did the multiplate samplers, resulting in species diversities 0.3 to 0.6 greater than those of the multiplate samplers. Diversity values were lower during 1972, except for the spring sample. Seasonal diversity varied from a low of 0.36 in the summer of 1972 to a high of 3.99 in the fall of 1971.
