Changes in reef community structure after fifteen years of natural disturbances in the eastern pacific (Costa Rica)
Abstract:Eastern Pacific coral reefs have been severely disturbed by natural events during the past two decades. We have monitored changes in reef structure and reef recovery after ENSO 1982–83 (starting in 1984), at sixteen permanent plots in four different habitats at Caño Island, Costa Rica. Reefs were also severely affected by dinoflagellate blooms in 1985, and by warming events in 1987, 1990–95 and 1997–98. The 1982–83 event caused approximately 100% coral mortality in shallow reef zones at Caño Island, particularly of pocilloporid species. Coral recruitment may have coincided with putative larval pulses during the various ENSO events or shortly after, as deduced by the presence of sexual recruits during 1987–88 and widespread sexual recruitment in 1993–94. Mortality of juvenile and adult colonies during the 1997–98 ENSO warming was low (5%), suggesting that populations of massive and branching corals may have been more tolerant of elevated thermal stress than during previous events. Supporting this notion are the Reynolds SST comparative plots for 1982–83 and 1997–98, which indicate similar warming trends and temperature maxima at this locality. Reefs at Caño Island are recovering, with significant increases in the number of new sexual recruits. Although 1984 levels of coral cover have not yet been attained island-wide, 70% cover occurs in reef areas on the north side of the island. Other disturbances, such as phytoplankton blooms that affected Pocillopora spp. in all habitats, may have retarded reef regeneration, complicating the course of recovery after the 1982–83 ENSO warming disturbance.
Document Type: Research Article
Publication date: July 1, 2001
More about this publication?
- The Bulletin of Marine Science is dedicated to the dissemination of high quality research from the world's oceans. All aspects of marine science are treated by the Bulletin of Marine Science, including papers in marine biology, biological oceanography, fisheries, marine affairs, applied marine physics, marine geology and geophysics, marine and atmospheric chemistry, and meteorology and physical oceanography.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites