by Verena Tunnicliffe, Marine Biologist, University of Victoria
June 30, 2010
This video shows just some of the stunning imagery captured by the high-definition cameras on the Little Hercules remotely operated vehicle (ROV) on June 30, 2010, during the vehicle's second dive down to Kawio Barat volcano. Video courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download video (mp4, 73.2 MB).
We are deep in one of the most exotic seas in the world – the centre of the Coral Triangle with the highest diversity of marine animals in the world. The Little Hercules remotely operated vehicle (ROV) is throwing a tiny spotlight onto deep-sea habitats rarely seen before our exploration. As we neared the first hydrothermal venting on the summit of Kawio Barat, the biologists were excited to discover what types of animals would inhabit the vents. Would we see the same animals that occur at vents in other areas of the western Pacific or would these vents have their own special character?
The Little Hercules ROV nears active hydrothermal vent sites on the summit of Kawio Barat submarine volcano. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.7 MB).
The Little Hercules ROV shines its lights on a veritable field of sulphide chimneys and rocks covered with shrimp. In a short period of time, a thriving community over a large area of diffuse venting was revealed. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.6 MB).
The first animals we sighted were clams sparsely scattered over the sediment. But then, as we came into the field of sulphide chimneys, we could see a veritable field of animals and chimneys festooned with barnacles and rocks covered with shrimp. On the chimneys where shimmering flow was higher, we also saw small worms in tubes, large limpets, and snails. It was a thriving community over a large area of diffuse venting.
The barnacles are particularly intriguing. They appear similar to forms seen near Lau and the volcanic arc north of New Zealand. They are a type of goose-neck barnacle that can wave around on a stalk. We watched as their tentacles (‘cirri’) extended like blooming flowers, then folded back into the shell. We know from similar animals at other hot vents that the white fluff on the cirri are filaments of bacteria that grow in the passing vent water. The barnacles hold out the cirri to grow the bacteria then, apparently, withdraw to “lick their fingers.” The overall effect of thousands of blooming barnacles was quite stunning.
Sulphide chimneys on Kawio Barat were completely covered with barnacles. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.8 MB).
The barnacles are a type of goose-neck barnacle that grow on a stalk. The white fluff on the cirri is filaments of bacteria that grow in the passing vent water. The barnacles hold them out to improve growth then, apparently, withdraw to “lick their fingers.” Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.6 MB).
Our first impression is that there is much more to learn here – about the animals and their habitat. We see crabs but what species? We see vent worms but are they the same as those from Lau Basin? And we see shrimp...not immediately recognizable even to the shrimp experts. These stars of the Celebes hot vents will await further exploration and study.
The Little Hercules ROV descends down to the summit of the Kawio Barat submarine volcano. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.3 MB).
The Little Hercules ROV images a vent plume as it descends to the summit of Kawio Barat submarine volcano. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.7 MB).
Scientists and spectators located at the Seattle Exploration Command Center intently watch live video being streamed from the Little Hercules ROV. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 2.0 MB).
The first animals we sighted were clams sparsely scattered over the sediment and white mats, both of which use vent fluids as energy for associated microbes. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.8 MB).
Zooming closer with the cameras on the ROV, we can see frozen sulphur rivulets covering the rocks. Molten sulphur at high temperature is black while the yellow sulphur indicates a lower temperature when molten. Diffuse vent fluids in the area promote the growth of bacteria, attracting dense populations of shrimp that graze on the food source. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.8 MB).
Scientists and spectators located at the Seattle Exploration Command Center watch as a thriving hydrothermal ecosystem unfolds before them in video footage streamed live from the seafloor. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 4.2 MB).
A closer look at a chimney surface reveals blue-white fluffy bacteria on and a white squat lobster, probably a grazer. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.6 MB).
The surface of the sulphide chimney has started to oxidize to an orange colour. A large scale worm lurks to the left; it is a predator with large jaws. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.7 MB).
In a new site, we can never know for sure what the animals are from images only, but this crab likely belongs to a group known only from hot vents. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.8 MB).
Cameras on the ROV reveal a field of sulphur chimneys completely covered with barnacles. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.8 MB).
Venting is still active through some of the chimneys. Here, a thin spire grows with a black tip and emerging water that is probably over 100°C (212°F). Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.7 MB).
View of the control room on board Okeanos Explorer during ROV operations. You can see live footage from the ROV on the left monitor, revealing sulphur chimneys covered with dense communities of barnacles on the seafloor. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 678 KB).
A dense assemblage of barnacles covered rocks and sulphur chimneys on Kawio Barat. Image courtesy of the NOAA Office of Ocean Exploration and Research, INDEX-SATAL 2010. Download larger version (jpg, 1.9 MB).
