Finding out what lives there

The new pump has a set of rotating chambers that make it possible to undertake several independent sampling operations in a single ROV dive. This represents a tremendous increase in sampling efficacy. It was only possible to test it once this summer, but it worked successfully on the new Ægir 6000 ROV, and gathered a number of samples from several different locations including a black smoker chimney, the low-temperature venting barite area as well as several sites away from active venting locations.

In addition to the suction pump samples, the video uptake on the Ægir 6000 gave the group good film material, something that is having increasing importance when studying organisms living in such inaccessible and inhospitable environments.

Completing the picture

Finally, the group had a chance to replicate a previous seafloor sample using the ROV’s “dig and scoop” drawer. The material gathered on a previous cruise was insufficient for all the tests they had hoped to be able to conduct. This summer’s bottom sample will provide complementary material including some tube worms, more vent amphipods, Exitomelita sigynae, and snails, both Skenea sp. and Pseudosetia sp.. Professor Hans Tore Rapp, leader of the Marine Biology research theme at CGB, hopes this material will enable his group to complete the description of the fauna around Loki’s Castle.

Photosynthesis vs chemosynthesis driven?

Future goals for this group would be for more “bottom time” to be able to gather more extensive samples, including some from areas not explored as yet, such as the so called, rubble zone below the chimneys. A number of organisms live in this area including sea anemones and fish. In order to understand more about this complex ecosystem, the group would also like to collect more environmental data about different environmental niches, for example close to the vents and some distance away. It would be optimal someday, to be able to collect data that could reveal information about seasonal variation and sedimentation rates over time. Such time series data would provide essential information about the impact of sinking biological material vs chemosynthetic production on this ecosystem.

Researchers from CGB’s deep sea marine biology theme are part of a larger marine biodiversity research group at the Department of Biology. Being able to share experiences, methods and techniques helps this latter group as a whole to understand marine biology across the oceanic ecosystem from tide-pools, to fjord waters, to coastal waters, to open seas and, finally, to the deep sea.

METAS AS