Where are you from, and what is your role in Extreme 2004?

I am a postdoctoral research associate working with Dr. Dave Caron and Peter Countway (Extreme 2003 cruise participant) at the University of Southern California (USC). We investigate single-celled organisms called protists using molecular methods based on DNA sequence information. In collaboration with Dr. Craig Cary, we examine protistan diversity and community structure at hydrothermal vents, and this is the second time that our lab has been invited to participate in the Extreme program. I will collect protists from the water column (within and around the hydrothermal plume) and from different locations within and surrounding the deep-sea hydrothermal vents for molecular analyses and for the isolation of protists to establish cultures.

What questions are you trying to answer and why?

The questions addressed in our research concern diversity, abundance, and activity of protistan assemblages in hydrothermal vent ecosystems. By using DNA-based technologies, we are able to detect and describe protists that are difficult to characterize by means of microscopy since cells often lack distinct morphological features. The resolution of electron microscopy helps resolve this issue for a number of species, but this technique is costly and labor-intensive. We will use molecular tools to investigate if protistan assemblages associated with the vent sites are unique to their environment and how abundant protists are at different sites within the vent ecosystem. In addition, culturing protists collected from the hydrothermal vent system (which was successful in 2003) will allow us to study their physiology and to link physiology with morphology and DNA sequence information for the isolated organisms.

Why is this research important? What are the benefits?

Protists play a fundamental role in aquatic ecosystems. Phototrophic protists (phytoplankton) are responsible for a majority of the primary production in the euphotic zone (the region of the water column illuminated by solar radiation) while heterotrophic protists feed on other protists and prokaryotes (bacteria and archaea) throughout the water column. Despite these facts, we have yet to better determine protistan abundances and describe species community composition in marine ecosystems and how both change with time. Addressing these questions for protists that live at hydrothermal vents is an important task that can help us understand how these single-celled organisms are able to cope with the harsh environmental conditions they experience at depth (e.g., high pressure, high temperature gradients, etc.) and what ecological role single species or functional groups of protists play in the cycling of energy and material through vent habitats.

What is your background, and what lured you into marine science/education?

Born in Austria, I came to spend all my summers at the Mediterranean Sea, which sparked my interest in marine biology. I returned to the northern Adriatic Sea to conduct fieldwork for my master's thesis, which dealt with coastal harmful algae blooms. Most of the sampling for this study required SCUBA diving, which I truly enjoyed. I graduated in zoology and ecology from the University of Vienna in 1995.

After my participation in a summer course at the Bermuda Biological Station for Research (BBSR) my interest in open ocean food webs lead me to conduct my Ph.D. fieldwork at BBSR. Under the supervision of Dr. Debbie Steinberg (BBSR) and Dr. Gerhard Herndl (University of Vienna), I investigated how crustacean zooplankton impact biogeochemical cycling in the Sargasso Sea. For three years, I participated in numerous monthly cruises with the Bermuda Atlantic Time-Series (BATS), whose main goal is to understand the ocean's role in global carbon cycling. While earning my sea legs, I enjoyed working as a teaching assistant for several courses, and upon completion of my Ph.D. in 2001 (University of Vienna) I returned to BBSR to instruct a course in Biological Oceanography.

In 2002, I moved to Los Angeles, California, to join Dr. Dave Caron's lab at the University of Southern California as a Postdoctoral Fellow. Since my arrival at USC, I have become involved in several interesting projects that focus on protistan biodiversity in different geographical regions such as the northeastern coastal Pacific, the North Atlantic, and the Southern Ocean. In addition, I study how protistan community structure is altered due to grazing pressure by crustacean zooplankton, and I am involved in the development of early detection methods for harmful algae species. My research experience at USC has allowed me to become proficient in molecular methodologies and has deepened my passion to try to understand and explore the field of marine biology and oceanography. I am greatly looking forward to my first participation in a hydrothermal vent cruise.