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2489635 
Journal Article 
Population expansion of a new invasive coral species, Tubastraea micranthus, in the northern Gulf of Mexico 
Sammarco, PW; Porter, SA; Sinclair, J; Genazzio, M 
2014 
1 
Marine Ecology Progress Series
ISSN: 0171-8630
EISSN: 1616-1599 
495 
161-173 
WOS:000330356000012 
An Indo-Pacific scleractinian coral has invaded the northern Gulf of Mexico (GOM): Tubastraea micranthus. It was initially observed on one oil platform (GI-93C) near the Mississippi River. Here, we determined whether its populations were spreading and whether there was evidence of rapid expansion. We compared population density data of T. micranthus with those from T. coccinea, a congener which invaded the western Atlantic earlier. Fourteen oil/gas platforms were assessed down to 138 m depth using remotely operated vehicle digital video. Colony den sities in numbers m(-2) were determined for both species, and colony size was measured for T. micranthus. Data were analyzed by platform and for geographic distribution. T. micranthus densities were highest on GI-93C and on GI-116A, SW of the Mississippi River, being significantly higher than on other platforms. Densities declined radially from there. Mean colony size was highest on MC-311A, with colonies generally being > 100 cm(2). This platform is situated at the head of the Mississippi Canyon and may have been the original site of colonization. It also receives blue water instead of turbid, lower salinity water, and this species may grow better under those conditions. T. micranthus size frequency distributions were generally skewed towards 1-200 cm(2) (5 cm diameter) (sometimes > 90% of the population), suggesting that most populations are potentially in an expanding growth phase. T. coccinea densities were high (range: similar to 50 to 300 colonies m(-2)). Its populations were also centered SW of the Mississippi River. T. micranthus is spreading through this region, and the window for its potential eradication may be closing. 
Coral; Invasive species; Tubastraea micranthus; Gulf of Mexico; Spread; Oil platforms