coral disease outbreak

[Harry McCarty]

Dear Colleagues, 

During the post-8th International Coral Reef Symposium field trip to 
the eastern Caribbean region of Panama 3-5 July 1996, Esther Peters 
and Jim Porter observed an extensive outbreak of yellow-blotch disease 
(YBD) on Montastraea spp.  This disease, also known as yellow-band 
disease, was discovered off Key West, Florida, by Craig Quirolo 
(Underwater USA, 11(8):15, 1994), and has appeared on only a few 
colonies of M. faveolata there.  Monitoring of this disease is 
continuing in the Keys (C. Quirolo) and histopathological and 
microbiological studies were recently initiated on samples from the 
Keys (Deborah Santavy and Esther Peters).  Similar signs of disease 
have been observed occasionally on colonies of M. faveolata elsewhere, 
but on reefs off the Salar Islands group approximately three-quarters 
of the largest (100-300 years old) M. faveolata colonies were affected 
by YBD.  Disease signs were seen less often on smaller colonies and 
on colonies of M. annularis.  YBD is characterized by: 

*  Circular to irregularly-shaped patches or wide streaks of lightened 
   tissue, occurring in no particular pattern on the surface of the 
   colony. 

*  Color of affected tissue is yellowish, not pale brown to bright 
   white as occurs in the condition known as coral bleaching, although 
   we found a few bright white bleached patches adjacent to yellowish 
   ones (Tissues are translucent and histologically symbiotic algae 
   remain in affected tissues, although reduced in number). 

*  Affected tissues otherwise appear normal. 

*  The lightened patches frequently, but not always, are adjacent to 
   or forming a perimeter around algal/sediment accumulations on dead 
   coral skeleton.  The algal/sediment accumulation is immediately 
   adjacent to living tissue, no "band" of clean, denuded, skeleton is 
   apparent. 

We are interested in learning more about the incidence and prevalence 
of this disease in the western tropical Atlantic and in collaborating 
on further studies to investigate its etiology.  We would appreciate 
learning of your observations.  Please send reports to Esther Peters 
at 73261.2212 at compuserve.com.  THANK YOU!