Survivorship and growth rates for some transplanted coral reef building species and their potential for coral reef rehabilitation in the red sea

Abstract

The deterioration of coral reefs in Egypt is a serious environmental problem. As part of studying the reef habitats rehabilitation; about 180 specimens of 8 hard coral reef species belonging to 2 families (Pocilliporidae and Acroporidae) were transplanted using table-type galvanized steel frameworks. Survival and growth rates were measured in situ then monitored over 24 months. From the transplanted 180 specimens, 128 fragments representing 71% were still survived after 4 months decreased to 121 fragments with a percentage of 67.2% after 12 months increased to 123 fragments (after recovery of two specimens) with 68.3% of the transplanted specimens after 24 months. Significant differences (P<0.05) in growth rates were observed among the three periods of investigation (4, 12 and 24 months) in both families. The mean growth rates of investigated species of Pocilliporidae; S. pistillata, P. damicornis and P. verrucosa after 4, 12 and 24 months were; 1.27±0.06 cm yr -1 , 1.2±0.07 cm yr -1 and 1.03±0.07 cm yr -1 (F = 3.43, 3.16 and 4.95) respectively. The investigated species of Acroporidae; Acropora tenuis, A. digitifera, A. horrid, A. samoensis and A. variabilis recorded the annual mean growth rates of; 0.56±0.02 cm yr -1 , 0.45± 0.04 cm yr -1 , 1.04± 0.05cm yr -1 , 0.83± 0.04cm yr -1 and 0.98± 0.03cm yr -1 (F = 17.58, 0.59, 0.60, 1.50 and 2.83) respectively. New coral reef recruits were observed for S. pistillata, P. verrucosa, P. damicornis and A. degitefera, but the coral recovery was observed for S. pistillata only.