[Coral-List] Coral reefs under threat

[Eugene Shinn]

     Some readers are claiming that coral die-offs like what is 
happening now in the Florida Keys has never happened before. I can't 
remember how many times I have suggested that corals have indeed 
perished along the main reef tract during the past 6,000 years. Seismic 
profiles and coring in large parts of the main reef tract showed that 
corals either never got started on many miles of the reef tract, or were 
exterminated by unknown causes. In those areas where the main reef tract 
is under 8-10m of water there has been less than 2 m of Holocene coral 
accumulation on the underlying Pleistocene reef ridge. Even the slowest 
growing corals could have kept pace with rising sea level during that 
time period. I encourage someone to do the research and determine why 
the corals did not keep pace with rising sea level. Was it water 
temperature or pollution? Remember this all happened long before humans 
invaded the Keys. Some well placed carbon 14 dates of dead corals 
attached to the underlying Pleistocene surface may help solve the problem.

      I recommend reading the extensive compilation of Keys research 
compiled by Barbara Lidz cited below. More than 2 decades of research is 
compiled in her USGS website below. Gene

Lidz, B.H., Reich, C.D., and Shinn, E.A., 2007, Systematic Mapping of 
Bedrock and Habitats along the Florida Reef Tract: Central Key Largo to 
Halfmoon Shoal (Gulf of Mexico): U.S. Geological Survey Professional 
Paper 1751 (300+ single-spaced hardcopy pages: DVD and online at 
http://pubs.usgs.gov/pp/2007/1751 <http://pubs.usgs.gov/pp/2007/1751>