TY - JOUR
T1 - Growth rates, densities, and distribution of Lophelia pertusa on artificial structures in the Gulf of Mexico
AU - Larcom, Elizabeth A.
AU - McKean, Danielle L.
AU - Brooks, James M.
AU - Fisher, Charles R.
N1 - Funding Information:
We wish to thank Matthew Schmidt, Miles Saunders, Jay Lunden, and Greg Boland for assistance at sea, Matthew Schmidt for assistance with image analysis, Erin Becker for assistance with statistical treatment of the data, Miles Saunders for assistance in preparation of Fig. 1 , three anonymous reviewers whose input significantly improved the manuscript, and the associate editor for extensive and insightful edits and suggestions. We thank the crew of the Brooks McCall from TDI Brooks International and the ROV operations team from the University of Connecticut without whom this work would not have been possible, as well as the oil and gas companies and their personnel who provided historical survey video and allowed us access to their platforms to conduct video surveys. This work was supported by BOEM contract M08PC20038 to TDI Brooks with vessel and submergence facilities support provided by National Oceanic and Atmospheric Administration's Office of Ocean Exploration and Research.
PY - 2014/3
Y1 - 2014/3
N2 - Using industry inspection video and ROV imaging, we examined Lophelia pertusa (Linnaeus 1758) on 10 artificial structures of known ages (9 to 100 years) in the northern Gulf of Mexico (GoM). Five different types deep-water energy installations with depths ranging from 320 to 995. m, and three shipwrecks with depths ranging from approximately 530 to 615. m, were examined. Density, depth ranges, and growth rates of L. pertusa colonies were calculated from video and image analysis. L. pertusa colonies were present on all structures examined. Minimum calculated growth rates for the largest colonies ranged from 0.32 to 3.23. cm/yr on the different structures. The shallowest depth at which L. pertusa was observed was 201. m and the deepest was 801. m, considerably expanding the known depth range of this species in the northern GoM. Colony density varied with structure type, age, and depth, with the highest density between 503 and 518. m on the single structure that spanned the entire depth range of occurrence of L. pertusa observed in this study. L. pertusa colonies growing on thinner and deeper installations appear to have higher colonization rates, i.e. to develop higher densities over a shorter time period, compared to those on shallower and more massive types of installations. However, on average, colonies have slower growth rates on these installations than colonies on more massive, shallower installations (compliant and solid installations). In general, the calculated minimum growth rates were higher on the installations than on the shipwrecks, which were substantially older. A continuum of colony sizes was documented on all installations, suggesting multiple settlement events. L. pertusa thickets were observed on the oldest anthropogenic structures, with most of the components of these structures covered by colonies of L. pertusa. Brown, orange, and mottled color-variants were documented for the first time in the GoM. All installations examined for this study were colonized by L. pertusa and it is likely that most artificial surfaces in appropriate depths in the GoM will be as well.
AB - Using industry inspection video and ROV imaging, we examined Lophelia pertusa (Linnaeus 1758) on 10 artificial structures of known ages (9 to 100 years) in the northern Gulf of Mexico (GoM). Five different types deep-water energy installations with depths ranging from 320 to 995. m, and three shipwrecks with depths ranging from approximately 530 to 615. m, were examined. Density, depth ranges, and growth rates of L. pertusa colonies were calculated from video and image analysis. L. pertusa colonies were present on all structures examined. Minimum calculated growth rates for the largest colonies ranged from 0.32 to 3.23. cm/yr on the different structures. The shallowest depth at which L. pertusa was observed was 201. m and the deepest was 801. m, considerably expanding the known depth range of this species in the northern GoM. Colony density varied with structure type, age, and depth, with the highest density between 503 and 518. m on the single structure that spanned the entire depth range of occurrence of L. pertusa observed in this study. L. pertusa colonies growing on thinner and deeper installations appear to have higher colonization rates, i.e. to develop higher densities over a shorter time period, compared to those on shallower and more massive types of installations. However, on average, colonies have slower growth rates on these installations than colonies on more massive, shallower installations (compliant and solid installations). In general, the calculated minimum growth rates were higher on the installations than on the shipwrecks, which were substantially older. A continuum of colony sizes was documented on all installations, suggesting multiple settlement events. L. pertusa thickets were observed on the oldest anthropogenic structures, with most of the components of these structures covered by colonies of L. pertusa. Brown, orange, and mottled color-variants were documented for the first time in the GoM. All installations examined for this study were colonized by L. pertusa and it is likely that most artificial surfaces in appropriate depths in the GoM will be as well.
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U2 - 10.1016/j.dsr.2013.12.005
DO - 10.1016/j.dsr.2013.12.005
M3 - Article
AN - SCOPUS:84892873346
SN - 0967-0637
VL - 85
SP - 101
EP - 109
JO - Deep-Sea Research Part I: Oceanographic Research Papers
JF - Deep-Sea Research Part I: Oceanographic Research Papers
ER -