I am an associate professor of marine biology and zoology at the University of Vienna, Austria. Andrea Nussbaumer, a Ph.D. student from my lab, and I have been invited on this cruise by Colleen Cavanaugh and are collaborating with her lab in the "search for the free-living symbiont in tubeworms." Additionally, I am currently funded by the Austrian Science Foundation for the study of the meiobenthic community — small animals in the size range up to 1 mm — at hydrothermal vents and for the study of the infection mode in tubeworms (the latter is Andrea’s Ph.D. work, and she will tell you about it).
What questions are you trying to answer and why?
Large animal communities provide microhabitat and refuge for meiofauna at hydrothermal vents, but at present, the composition, the distribution, and especially the ecological role(s) are unknown. We will characterize the meiofauna community of the East Pacific Rise (9°50’ N) hydrothermal vents and the adjacent off-axis sediments so that the species diversity, abundance, biomass, and distribution are documented according to well-characterized habitats within this ecosystem. This information will allow us to distinguish communities within the spreading center between active and inactive sites, either hard substrate, sulfide precipitates, or soft sediments and the off-axis ridge areas. From these descriptive data, underlying evolutionary and historical processes may be invoked and hypotheses on the origin and evolution of vent meiobenthos can be developed. These data will also enable the estimating of meiobenthic biodiversity, to distinguish and characterize the meiobenthic communities and to estimate their ecological impact. Within this framework, our work will greatly increase the understanding of the entire hydrothermal vent community and of interactions therein.
Why is this research important?
We know from many studies carried out over the past 15 years that only a few marcrofauna species are adapted to live in this extreme environment. The species number is low, but the abundance of these species is very high. However, the small meiobenthos has received so little attention during this time that we still do not know if these small animals follow the same trend. In order to understand an ecosystem, I believe it is important to consider the entire community. Also by discovering and describing new species, this work can contribute to our knowledge on the biodiversity that exists in the oceans.
What is your educational background? What lured you into marine research?
As an Austrian having grown up in a land-locked country, the sea was far away for me. However, every summer my parents took me to the northern Adriatic Sea on vacation. My fascination with the sea started when I first learned how to swim in the sea and collected shells from the beach. Of course this created a strong personal link to holidays for me at that time. Only much later, becoming a zoologist and marine biologist, did I learn that going to sea meant work.
Initially, I was mostly interested in the evolution and phylogenetic relationships of lower marine worms, but later I became fascinated with symbiosis. Some worms living in the sands of coral reefs are completely covered with a fur of bacteria. These hosts carry their symbionts to sand layers, where chemicals are available for carbon fixation. In return, some of the bacteria serve as food for the host. Also close to the coral reefs, mangrove swamps harbor similar symbiosis — for example, a colonial ciliate. Like the worms, the ciliates also live on their bacteria.
After receiving my Ph.D. from the University of Vienna in 1992, I was fortunate to be invited on a cruise to the deep-sea hydrothermal vents of the East Pacific Rise. I became hooked on this remote marine environment when I went on my first dive in Alvin. I wanted to study the giant tubeworms. But how could I do that as an Austrian without having access to a research vessel and a submersible? So I decided to work on tropical shallow-water symbiosis for a few post-doc years in Germany and the U.S. before I found the courage and opportunity to move my research into the deep sea. Now more than 10 years after my first dive, I have been invited on 7 cruises to the hydrothermal vents and was able to take along 5 of my students on U.S. research vessels. Just recently, for the first time in Austrian history, I received funding to rent a submersible, but this will occur later, sometime during the next year.
