Table 1. Physical descriptions of habitat types present at Pelekane Bay, Hawai'i and a summary of their major biological features. Habitat types follow those described in Chaney et al. (1977). Habitat Type 1: Mixed rubble and silt bottom Depth to 1 m. Substrate defined as loose small to medium-sized coral rubble or debris with coral fragments up to 20 cm in diameter. Alternating compositions of sand and silt mixed with coral rubble. Substrate was commonly covered with filimentous red algae and super-surface algal mats. Encrusting coralline algae was seen, but rare. Macro-invertebrates that were observed, but rare, include burrowing shrimp and isopods. Box crabs were commonly seen. Chelonia midas were commonly observed on sandy bottoms. Habitat Type 2: Sand and silt bottom Depth ranged from 1 - 3 m. Visibility was usually very poor—between 0.5-1.0 m. Substrate was primarily composed of silt and sand. Shrimp burrows were quite abundant, ranging from 0.5 cm - 4 cm in diameter. Distinct channeling of silt between shore and patch reef area. Chelonia midas were observed but rare. Habitat Type 3: Basalt pavement with rubble Depth was 0.5 - 3 m. Southern side of bay composed of basaltic pavement and large boulders. Visibility usually ranged between 1-3m. Macro-invertebrates commonly seen were Echinometra mathaei, E. oblonga, Echinothrix diadema, E. calamaris. Other invertebrates that were seen include Anthelia edmondsoni, Zoanthus specificus, and turf algae. Common fish were juvenile Acanthurus triostegus and Mulloidichthys spp., Kuhlia sandvicensis and Mugil cephalus. Habitat Type 4: Coral in mixed rubble Depth usually between 0-1m. Characterized by small dead coral heads on a silt-sand substrate (off Eastern point) and offshore. Some Pocillopora damnicornis and isolated patches of Porites lobata were observed. Filamentous algae and Porolithon onkodes were common. Habitat Type 5: Patch reefs Patch reefs were 1-4m in depth. Habitat Type 5 had the greatest visibility on all occasions ranging from 2-4m. Large vertical relief of coral formations that were up to 4m in diameter. Most coral formations were dead due to extensive sedimentation or coverage by dead coralline algal mats. Live corals were sparsely distributed patches of Porites lobata interspersed with Pocillopora damnicornis, Porites compressa, and Pavona varians. Large areas were abundantly covered with Porolithon gardeneri and P. onkodes. Few macro-invertebrates were found. Those that were included Echinometra mathaei.
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