Noncommercial benthic fauna

Eastern Bering Sea


The bryozoan, Carbasea serrulata.

Phylum Bryozoa

Species Representatives: Eucratea loricata, Carbasea serrulata, Escharopsis lobata, Rhamphostomella costata

Distribution and Life History: Bryozoans are small colonial animals that are common on hard substrates in the SE Bering Sea. They can be easily confused with hydroids and corals. Each individual (called a zooid) in a bryozoan colony is interconnected. Some species produce a non-feeding larva with a brief, free-swimming period, while some larva persist for several months (Barnes, 1980). Only the largest, most conspicuous species have been identified from the NMFS SE Bering Sea trawl survey, although none are routinely identified. About 90 species of bryozoans have been identified in the SE Bering Sea., but intensive collecting might double that number (3). Roughly two-thirds of the area's known species are low profile encrusting forms. Rock, live and dead bivalve and gastropod shell and crab shells are common substrates for attachment. Age and growth rates of bryozoans vary, but many species in the SE Bering Sea probably mature in one to three years (3).

In Lower Cook Inlet, Alaska, the bryozoans Flustrella sp. and Dendrobeania spp. were associated with the largest catches of juvenile red king crab (Paralithodes camtschatica)(Sundberg and Clausen, 1977). Bryozoans were a common component of young-of-the-year red king crab habitat on the west Kamchatka Shelf (Tsalkina, 1969), and they were the substrate of choice in laboratory experiments with young-of-the-year, and 2-3 year old red king crab (Babcock et al., 1988).

Eucratea loricata (feathery bryozoan) - Height to 18 cm; flexible structure. Common north of the Alaska Peninsula (Kessler, 1985).

Carbasea serrulata (Flustra serrulata (leafy bryozoan) in Kessler (1985)) - Height to 15 cm; flexible structure. Uncommon north of the Alaska Peninsula (Kessler, 1985).

Escharopsis lobata (Escharopsis sarsi (crusty bryozoan) in Kessler (1985)) - Length to 8 cm; rigid structure. Uncommon north of the Alaska Peninsula (Kessler, 1985).

Rhamphostomella costata (ribbed bryozoan) - Length to 8 cm; rigid structure. Uncommon north of the Alaska Peninsula (Kessler, 1985).