Cold-water coral colonies are long lived as sessile adults (hundreds to thousands of years). Impact of the Deep water Horizon oil spill impacted several CWC ecosystems and their survival rates. Figure 7, shows Paramuricea sp. and Asteroschema sp. found in the Mississippi Canyon, 20 km from the Macondo well, showed coverage of brown flocculent material. In the area of 100m, the thick, deep water consisted petroleum hydrocarbons from the Macondo well in June 2010, which left behind impacts on the deep water ecosystem. There were visual signs of tissue damage and loss as well as tips of branches in the red boxes (figure 7), showing change in coverage of flocculent material. As you can see, the coverage is less in December 2010 but high in November 2010 which was due to these oil spill impacts. Many coral colonies showed a variation of stress such as sclerite enlargement, abundant mucous production, bleached ophiuroids, and brown flocculent material coverage. There was strong evidence that the oil from the Macondo well caused damage and death to cold water ecosystems, leaving a large impact on CWCs found on these sites (White et al, 2012).
Oil and gas exploitation and decommissioning affect corals and animals associated with CWC reefs. High powered air guns are used to locate hydrocarbon deposits have been tested. These substances such as hydrocarbons, drill cuttings, mud and sediment extraction has left corals poisoned and smothering them. Oil pipelines and construction crushes corals on the seafloor and removes any rocks that CWCs have attached themselves to (Hysing et al, 2013).