East Pacific Rise Cruise 2004: Extreme 2004

FWF research project No. P16774-B03

Projects:

Quantitative Meiobenthos Collections

Discovery of a new Nemertine

The Search for Babies

Baby Traps – The next generation

DOC grant, Academy of Science

Collaboration with scientists and crew

11/29/2002 - 12/20/2004

Chief scientist: C. Cary (University of Delaware, USA)

Austrian participants:

Monika Bright

Research Vessel Atlantis

Deep Submerged Vehicle Alvin

We were invited to continue our research at deep-sea hydrothermal vents at the East Pacific Rise f9°N. We would like to thank C. Cary and his team for their support.

More informations about Alvin and Atlantis and all cruises are provided on the WHOI website.

Further informations about the Cruise Extreme 2004 and a Cruise diary (in german) are provided on the Extrem for Kids website.

Quantitative Meiobenthos Collections 2004

This time, we were able to collect several samples from Alvinella pompejana aggregations on sulfides. This habitat is extremely interesting to us because it is the hottest vent environment inhabited by animals. However, not only a few macrobenthic animals were found there, but we discovered also meiobenthic animals, mostly copepods.

Available diploma theses: Meiobenthos

                    Collection of meiobenthos from Michael’s vent                                        Copepod from Alvinella aggregation

Discovery of a new Nemertine

In a collection of Riftia during the dive #4073 at the sulfide mount 13 °N , we found several small, pink worms. They are undecribed nemertines and are currenty investigated.

                                  Riftia aggregation from 13 °N                                                         Pink nemertines from Riftia aggregation

Hochschuljubiläumsfond der Stadt Wien, Academy of Science

The Search for Babies

In December 2003, we deployed 5 artificial settlement devices (Baby traps) in a clump of large tubeworms. Unfortunately, these devices were displaced somehow during the last year. When returning to the site, we found them on bare basalt with no baby tubeworms on them.

                       Deployment of babytraps December 2003                                            Recovery of babytraps December 2004

Baby Traps – The next generation

In order to prevent displacement and loss of traps in large aggregations, we used a different design of deployment. The babytaps were mounted on 2 m long glass fibre sticks and deployed in a large Riftia aggregation at Tica.

We would like to thank the Alvin crew and especially senior pilot Bruce Strickland for the design and building of the devices. In honor of Bruce we name the next generation of Babytraps ‘Bruce’s sticks’.

                                           Bruce Strickland with ‘Bruce’s sticks’                                      Mounting ‘Bruce’s sticks’ on the basket of Alvin

            Deployment during dive#4071, Monika’s dive                                               Bruce’s sticks in large Riftia aggregation at Tica

DOC grant, Academy of Science - Incubations of Riftia pachyptila

The smallest symbiosis ‘unit’ is the host bacteriocyte housing the endosymbiotic bacteria. The distribution and morphology of the bacteriocyte within the trophosome suggests that a specific cell cycle with terminal differentiation is present. In order to test this hypothesis we conducted a time series of incubations using 3H thymidine and Brdu (a thymidine analog), which are incorporated in DNA during synthesis.

            Sampling of large Riftia on which juvenile tubeworms settle                                        Searching for small tubeworms for incubations