Title

Life history strategies and population dynamics of stony corals (Cnidaria: Scleractinia) in marginal habitats of the Bahama banks: Implications for long-term survival and persistence of coral communities

Date of Award

2007

Availability

Article

Degree Name

Doctor of Philosophy (Ph.D.)

Department

Biology

First Committee Member

Kathleen Sullivan Sealey, Committee Chair

Abstract

This thesis examined near shore, non-reefal coral community and population ecology of The Bahamas. Near shore coral communities are incredibly dynamic through space and time, and assemblages are highly responsive to micro-habitat conditions. Analyses completed across geographic and geological gradients confirmed strong island and habitat effects on conspicuous epifauna presence and abundance throughout The Bahamas. These findings strengthened the importance of linking different scales of physical factors (i.e., attributes of island and benthic habitat type) structuring organism distribution and abundance patterns in characterizing coral communities. "Marginal" (suboptimal) habitat coral subpopulations and individual colony growth and survival rates did display some degree of flexibility in response to natural and artificially imposed fluctuations in environmental conditions, as well as the acute disturbance regimes of a hurricane. Subpopulation structure changes over time were highly species-specific, and individual colonies also displayed species-specific responses to transplantation between marginal habitat types. Massive, relatively long-lived k-strategist species such as S. siderea, M. annularis, D. strigosa and D. clivosa overall responded more positively to habitat mitigation attempts employing artificial reefs, while "weedier" r-strategist species, such as F. fragum and S. radians, were overall less accommodating of transplantation to a more complex habitat structure. The assemblage patterns of communities, changes in populations, and responses of individual coral colonies documented in this study implicate micro-scale habitat conditions (often specific to one survey site) as major influential forces on marginal habitat organism dynamics. "Marginal" coral habitats, such as patch reefs, hardbar, and seagrass habitats, may be incredibly important to coral metapopulation persistence, as these habitat types are more common in The Bahamas than reefs, cover wider areas, and support highly dynamic coral subpopulations and benthic invertebrate communities.

Keywords

Biology, Ecology; Biology, Oceanography

Link to Full Text

http://access.library.miami.edu/login?url=http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3267725