 |
Low_Res_Image
Audio WAV file |
STUDY SITES: Lophelia reefs are well-developed on the two northern Gulf of Mexico Viosca Knoll sites investigated by USGS in 2004-2005. |
 |
Low_Res_Image
Audio WAV file |
VK906-862-MAP: Bottom topography on the Viosca Knoll study sites is rugged, with hard substrate raised by an underlying salt dome (multibeam imagery from the U.S. Navy submersible NR-1). |
 |
Low_Res_Image
Audio WAV file |
BIG BLUE REEF: Lophelia coral populates the flanks of elevated ridges on the Viosca Knoll 826 study site, as illustrated in this acoustic profile. A well-developed Lophelia reef occurs at this site. |
 |
Low_Res_Image
Audio WAV file |
SULAK SUB: Lophelia mission Chief Scientist, Ken Sulak, about to enter the acrylic observation sphere of the DSRV Johnson-Sea-Link submersible, in preparation for launching a deep-coral research dive from the RV Seward Johnson mothership. |
 |
Low_Res_Image
Audio WAV file |
SUB COLLECTION: Capable of multiple sampling operations, the JSL submersible uses it manipulator arm to deploy a coral collection wire basket, while simultaneously suctioning up a large brisingid brittlestar (Novodinia antillarum). |
 |
Low_Res_Image
Audio WAV file |
FISH TRAP DEPLOYMENT: USGS scientists prepare to deploy a baited fish trap in 350 m of water from the RV Tommy Munro. Several types of remotely-deployed sampling devices launched from a surface research vessel supplemented in situ submersible sampling and video operations on Viosca Knoll continental slope study sites. |
 |
Low_Res_Image
Audio WAV file |
LOPHELIA REEF DIVERSITY: On the 350 m deep Viosca Knoll study site, arborescent pure white Lophelia coral is just one of many sessile invertebrates comprising a diverse fauna of particulate feeders. Others include clustered lollipop glass sponges, solitary irregular desmo-sponges, and several species of anemones. |
 |
Low_Res_Image
Audio WAV file |
LOPHELIA CLOSE UP: When feeding, Lophelia polyps, with their nematocyst-laden tentacles extended into the current, are formidable predators. The beauty of the flower-like polyps belies their deadly purpose. They can rein in tiny plankton, but also capture active crustaceans up to 2 cm in length. |
 |
Low_Res_Image
Audio WAV file |
FLYTRAP ANEMONE (Actinoscyphia saginata): Stunningly beautiful but deadly, the large reddish-orange Venus flytrap anemone (Actinoscyphia saginata), behaves much like its terrestrial namesake, rapidly closing in upon and engulfing prey stunned by the corona of stinging tentacles. |
 |
Low_Res_Image
Audio WAV file |
BLACKBELLY ROSEFISH (Helicolenus dactylopterus): In a world illuminated only by pale blue biological luminescence, the strikingly beautiful red and white reticulation of the Blackbelly Rosefish (Helicolenus dactylopterus) actually serves as a cryptic camouflage, rendering this stationary ambush predator virtually invisible against the irregular reef background. |
 |
Low_Res_Image
Audio WAV file |
HITCHHIKING LOBSTER ON CUCUMBER: On open soft substrate,away from the hard substrate of the deep reef, attached particulate feeders are replaced by deposit feeders like this unidentified sea-cucumber (Holothuroidei), and a hitchhiking squat lobster, also unidentified. |
 |
Low_Res_Image
Audio WAV file |
GORGONIAN (Callogorgia americana delta) SNAKESTAR (Asteroschemia?): 'Soft corals', like this 2-m tall Callogorgia americana delta gorgonian, are locally important members of the deep-reef fauna. This species plays host to a large commensal snakestar (Asteroschemia?) that entwines its long fleshy arms throughout the gorgonian branches. The nature of the commensal relationship remains a mystery. |
 |
Low_Res_Image
Audio WAV file |
ELASIPOD HOLOTHURIAN: A swim and drift deep-water vagrant, this delicate and elegant gelatinous elasipod holothurian (Peniagone sp.) extends its webbed 'sail' to catch the current. Several species of pelagic sea cucumbers episodically are capable swimmers, descending to the substrate for mouthfuls of sediment, digesting the organic matter therein, then moving along. |
 |
Low_Res_Image
Audio WAV file |
CRINOID GLASS SPONGE: The stony surface of Lophelia provides a holdfast for the glass sponge (Aphrocallistes), in turn providing an elevated feeding perch for a particulate-feeding 9-armed antedontid crinoid (sea-lily). |
 |
Low_Res_Image
Audio WAV file |
BEGGATOIA BACTERIAL MAT: Where hydrocarbons emerge from the rock substrate, the bacteria Beggatoia forms thick fuzzy whitish mats. |
 |
Low_Res_Image
Audio WAV file |
BLACK CORAL ANEMONES: 2-3 m tall red black coral trees (Leiopathes cf. glabberima) are up to 3000 years old, among the oldest living organisms on earth. |
 |
Low_Res_Image
Audio WAV file |
BLIND LOBSTER: In DeSoto Canyon, just east of Viosca Knoll and away from rock and reef biotopes, the seafloor is a thick, fine-grained sediment. This soft, clay-like material enables the blind lobster (Acanthocaris caeca) to excavate large, deep burrows, often with a second or third entry. |
 |
Low_Res_Image
Audio WAV file |
BRISINGID BRITTLESTAR: Sitting upside-down atop a Lophelia coral bush, arms extended into the current, the large orange-red brisingid brittlestar (Novodinia antillarum) gathers food from the water column , then bends an arm in toward the central mouth to make the transfer. |
 |
Low_Res_Image
Audio WAV file |
CIRRIATE OCTOPOD: An evolutionary oddity, the distinctive cirriate octopus (Opistoteuthis agassizi) retains small swimming fins (like a squid), and has the arms joined by a membranous web. A necklace of pale blue bioluminescent spots rings the head. |
U.S. Department of the Interior |
U.S. Geological Survey
