Coral Community Structure at Pearl & Hermes Atolls NW Hawaiian Islands (Kenyon)
Channel: Ronald Cannarella
Date: 2012-06-02

A presentation at the Hawaii Conservation Conference by Jean Kenyon1, (Matthew Dunlap1, Casey Wilkinson1, Kimberly Page1, Peter Vroom1, Greta Aeby2, Oliver Dameron1
1NOAA Pacific Islands Fisheries Science Center Coral Reef Ecosystem Division, Honolulu, HI, 2Hawai‘i Department of Land and Natural Resources, Division of Aquatic Resources, Honolulu, HI) on "Coral Community Structure at Pearl and Hermes Atoll in the Northwestern Hawaiian Islands: Unique Conservation Challenges in the Hawaiian Archipelago". The distribution and abundance of scleractinian corals at Pearl and Hermes Atoll, Northwestern Hawaiian Islands, were determined from georeferenced towed-diver surveys covering more than 85,000 m2 of benthic habitat and site-specific surveys at 34 sites during 2000 – 2002. Three complementary methods (towed-diver surveys, videotransects, and photoquadrats) were used to quantify percent cover of corals by genus or species in the forereef, backreef, lagoon, and channel habitats. Three genera – Porites, Montipora, and Pocillopora – account for 97% of the coral cover throughout the atoll, although their relative abundances vary considerably according to habitat and geographic sector within habitats. Forereef communities are dominated by massive and encrusting Porites, while the backreef is dominated by Montipora, and the lagoon by Porites compressa. All taxa also show habitat-specific differences in colony density and size-class distributions, as assessed through colony counts within belt transects at fixed sites. These demographic data, which provide the most thorough quantitative description of the coral communities at Pearl and Hermes Atoll produced to date, are used to focus a discussion on risks of reef degradation from salient contemporary hazards including bleaching, disease, marine debris, and Acanthaster predation. Coral communities at Pearl and Hermes Atoll may be the most vulnerable in the Hawaiian Archipelago to bleaching and accumulation of marine debris, thus these corals may warrant special management attention. These data also provide a detailed baseline to which population parameters derived from long-term monitoring surveys can be compared to assess the direction, pace, and drivers of change.

Hawaii Conservation Alliance
Executive Producer: Ronald Cannarella