Jh. Hudson et al., ENVIRONMENTAL IMPLICATIONS OF GROWTH-RATE CHANGES IN MONTASTREA-ANNULARIS - BISCAYNE-NATIONAL-PARK, FLORIDA, Bulletin of marine science, 54(3), 1994, pp. 647-669
Long-term annual growth rates were determined for 25 Montastrea annula
ris colonies at eight reef sites in Biscayne National Park, Florida, X
-radiographs of slabbed coral cores revealed chronologies that average
d 113.5 years in length with a range of 40 to 242 years. A total of 2,
837 annual growth increments were identified and measured. Dating of d
ensity bands was verified by visually crossdating fluorescent bands wi
thin the coral skeleton. Average accretion rates of individual colonie
s varied from 5.0 mm.yr-1 in the northernmost sector of the Park to 11
.3 mm.yr-1 in the southernmost sector. Long-term growth rates of most
corals in this study were greatest prior to about 1950 except for a ma
jor, 3-5 year, decline in the growth record of older corals centered a
round 1878. Waxing and waning coral growth rates are discussed in rela
tion to natural and anthropogenic perturbations that impact this high
latitude reef ecosystem. Attention is drawn to nutrients from sewage o
utfalls as a possible contributing factor to observed growth rate decl
ine since 1950.