SPECIES COLLECTED, FEEDING HABITS, AND TROPHIC LEVEL RELATIONSHIPS The principal species collected were selected because they are commonly eaten by the Marshallese; relatively abundant; have different feeding habits; and for some, represent species for which previous available at Enewetak and Bikini for comparison. radiological data was It was not always possible, however, to obtain an adequate number of the same species at every location we sampled because of tides, insufficient time, unavailability of a species, and depletion of a species at inhabited atolls. Various reef fish were collected. Mullet Neomyxus chaptalii are herbivorous, detrital Convict surgeonfish Acanthurus and filamentous. algae that grow on reef rock or on the base of dead coral. The growing on herbivorous Naso lituratus, sandy and browsers garbage dump areas. browsers. All browsers and fronds unicornfish herbivorous crenilabis feeders that ingest considerable quantities of bottom sediment along with food. triostegus are Crenimugil also rocky but feeding a herbivore, areas. will on small browses Rabbitfish occasionally algal feed on larger Siganus on fleshy seaweed rostratus items are found in Rudderfish Kyphosus cinerascens are strictly herbivorous 8 the above fish belong to the second trophic level. of Goatfish Mulloidichthys other benthic fauna including small clams, crustaceans, other invertebrates, and small fish. This species belongs to samoensis the consume third fossorial trophic and level. ® Threadfin Polydactylus sexfilis feed strictly on benthonic fauna and also belong to the third trophic level.° Parrotfish Scarus sordidus are common’ reef-dwelling, omnivores feeding on live coral heads and occasional algae. grazing Parrotfish are in the fourth trophic leve1.® Four crocea, species of clams, Tridacna gigas, and Hippopus hippopus were collected. sessile, filter-feeding mollusks that live Tridacna squamosa, These large the lagoon on Tridacna invertebrates are bottom and coral reefs. Larger benthic, midwater, collected from the lagoons. the third trophic level and surface carnivores were also occasionally Grouper Epinephelus sp. are benthic carnivores of that feed on small fish and invertebrates. ° Jacks Caranx melampygus and Elegatis bipinnulatus (rainbow runner) are fast~swimming carnivores that feed on small fish occasionally eat swimming crustacea. and squid. Elegatis bipinnulatus may Snappers Aprion virescens (grey snapper) and Lutjanus bohar (red snapper) are hovering midwater-to-surface carnivores.