Plankton collected in the bay of Villefranche-sur-Mer by Johan Decelle, and imaged with a confocal microscope (Olympus) with a 10x lens under fluorescence (488nm). The images represent projections of 25 shots (spacing: 2mm).

Imaging during Tara Oceans

The imaging platform onboard Tara is referred to as T.A.O.M.I. (TAra Oceans Marine biology Imaging platform). It is dedicated to marine biology and the observation of plankton organisms (from a few micrometres to one centimetre). It allows three main types of assessments: flow analysis, microscopy and macro-photography.

The flow analyses continuously measure the variations of the surface water and of its plankton (number, sizes, photosynthesis efficiency…), but also allows to photograph the samples collected at various depths by the collecting devices located at the stern of Tara or by the plankton nets. It consists of four apparatus:

- the FRRF (Fast Repetition Rate Fluorometry), which allows to measure the photosynthesis efficiency. It is provided by Zbigniew Kolber, Monterey Bay Aquarium Research Institute, USA.
- the SeaFlow (continuous flow cytometer), which allows to assess accurately in time and space the distribution of the microscopic algae populations. This prototype is developed by Jarred Swalwell at the Washington University, Seattle, USA.
- The NASA analyses several physio-chemical parameters of the water.
- The FlowCam is an equipment consisting of a cytometer and a microscope enabling to swiftly follow organisms of very different sizes. It was developed by Mike Sieracki, Bigelow Laboratory for Ocean Sciences, USA.


On board Tara, imaging is processed in four different ways: underwater imaging, stereomicroscopy, fluorescent microscopy and fluorescent microscopy with phase. This allows to examine the plankton under low resolution in its natural environment, then to measure more accurately on board with specific markings and create 3D reconstructions of some organisms. The apparatus taken on board consist of:
- a UVP (Underwater Video Profiler) developed at the Villefranche-sur-Mer Marine Station. It allows to examine the plankton during its collection.
- a stereomicroscope to view, sort, dissect and prepare the plankton under low magnification.
- a fluorescent stereomicroscope for high definition imaging and 
- a fluorescent stereomicroscope with phase, a prototype from the Optical Microscopy Laboratory of the European Molecular Biology Laboratory, for three-dimensional imaging.

Finally, TAOMI also includes a macro-photography studio to illustrate the behaviour of a number of organisms making up the plankton (video), the photography of large organisms (larvae, jelly-fish…), and crucially of corals and macroscopic algae. It includes a horizontal fish tank and a vertical fish tank fitted with an articulated arm, various colour backgrounds and a low energy consumption lighting (LED).

TAOMI is not exclusive to Tara, because a number of observations are simply impossible to carry out on board: some types of microscopy require an improved optical stability, significant electrical energy consumption or the preparation of too complex or toxic samples. TAOMI on-shore is divided between the parent institution at the Dublin College University in Dublin, Ireland (Officer in charge: Dr Emmanuel G. Reynaud) and the stations: EMBL, Heidelberg, Germany (Officer in charge: Dr Eric Karsenti), Villefranche-sur-mer (Officer in charge: Dr Christian Sardet), Roscoff (Officer in charge: Dr Ian Probert) and also Naples (Officer in charge: Dr Giovanna Benvenutto). TAOMI on-shore can also carry out high-speed confocal microscopy as well as X-ray (Officer in charge: Dr Renaud Boistel).

Transformation of Tara

In order to accommodate T.A.O.M.I., Tara had to undergo modifications. One of the cabins had to be completely stripped out and transformed. It is now air-conditioned, and fitted with a pumping system to provide the FRRF and SeaFlow with surface sea water for the flow measurements. In addition, benches have been fitted to support the various equipment and for the preparation of samples. This miniature microscopy room also includes the FlowCam, the microscope with phase, a small incubator to keep the samples alive and a vertical fish tank for the macro-photography operations. Moreover, the bow saloon has also been adapted to fit a second microscopy room. It includes an observation post, which can accommodate the two stereomicroscopes, and the video/macro-photography studio for the investigation of corals and other algae with the help of a long articulated arm.


Contacts:

Officers in charge:    
Dr Emmanuel G. Reynaud    UCD, Dublin, Ireland
Dr Christian Sardet    Villefranche-sur-mer, France

Flow assessments:
Dr Zbigniew Kolber     Monterey Bay Aquarium Research Institute, USA.
Dr Jarred Swalwell     University of Washington, Seattle, USA.
Fluid Imaging Inc.     USA

Underwater imaging:
Dr Gaby Gorsky     Villefranche-sur-mer, France

Stereomicroscopy and phase microscopy :
Dr Emmanuel G. Reynaud    UCD, Dublin, Ireland
Dr Uroš Kržič  EMBL, Heidelberg, Germany

Macro-photography:
Dr Eric Roettinger     University of Hawaii, USA