MEPS 458:103-122 (2012)  -  DOI: https://doi.org/10.3354/meps09726

ABSTRACT: Internal bioerosion by macroborers (polychaetes, sipunculans, bivalves, and sponges) was investigated in dead Porites branches collected from 8 coral reefs along the Kenyan coast, 4 and 6 yr after the 1998 mass mortality of corals. Levels of nutrients, benthic cover, and numbers of grazing and invertebrate-eating fish and sea urchins were measured and evaluated for their influence on macrobioerosion. The macroboring community composition was influenced by the grazer composition on each reef; worms were the major macroboring agent where sea urchin biomass was high, and sponges were the dominant agent where herbivorous fish biomass was high. Bivalves accounted for a small proportion of the internal bioerosion and were not measurably influenced by consumers or water quality. The total macrobioerosion rates in Porites branches ranged from 534 ± 70 to 1134 ± 44 g CaCO₃ m⁻² (4 yr after the coral death) and 837 ± 111 to 2149 ± 314 g CaCO₃ m⁻² (6 yr after the coral death). The macrobioerosion rates were linearly and positively correlated with chlorophyll a concentrations (chl a) in the water column 4 and 6 yr after the coral death. Sponge boring rates were also positively correlated to chl a 6 yr after coral death but not after the initial 4 yr. Consequently, the macrobioerosion rates responded to nutrient status, but the community of borers changed with the dominant grazers, which in turn were influenced by fisheries management.

KEY WORDS: Calcium carbonate · Climate disturbance · Kenya · Marine protected areas · Monitoring · Pollution · Reef framework · Thermal anomaly

Full text in pdf format

Cite this article as: Carreiro-Silva M, McClanahan TR (2012) Macrobioerosion of dead branching Porites, 4 and 6 years after coral mass mortality. Mar Ecol Prog Ser 458:103-122. https://doi.org/10.3354/meps09726 Export citation Share:    Facebook - - linkedIn