Scientific Diving for the Research Topics: Marine Aquaculture, Maritime Technologies and ICZM
As a consequence of the location of the majority of our projects being in the open water of the German Bight research requires assistance of both research vessels and scuba diving. While ship time is readily available and supplied by the AWI fleet, sampling, deployment, and retrieval of scientific equipment is mainly performed by our research diving crew.
At the AWI training for scientific divers is provided on the North Sea island Helgoland. In the course trainees get experience in dry suit diving, snorkelling, apnoe diving as well as the theory of diving, physical principles, diving medicine and first aid. The final examination is done by the Hauptverband der Berufsgenossenschaften (HVBG), the board, which also regulates scientific diving in Germany.
Fig. 4: For most of our diving offshore the RV Uthörn is our home, but our diving usually takes place from a Zodiac. Below members of our dive crew and RV Uthörn do routine maintenance work on our offshore longline for the project AquaLast.
Fig. 3: Unlike in the heated swimming pool our work in the cold waters offshore requires wearing dry suits and due to the low visibility we often have to use lamps. Depending on the nature of the work we have to carry and manipulate a wide range of tools underwater.
Fig. 2: Part of the course is done in a swimming pool where basic scuba diving skills and apnoe diving are learned.
Fig. 1: On Helgoland the small vessel Diker is used as a diving base, the image below shows a dive crew in action.
Fig. 6: The image above shows a 60 m longline installation moored at our test site AquaLast off the island of Sylt. The longline has been brought to the surface for maintenance reasons and so the test bodies and attached buoyancy devices can be clearly seen. The whole installation was build up by our team of scientific divers. This was an extremely challenging task as heavy equipment needed to be handled in a safe way in the often rough conditions of the North Sea.
Fig. 5: If samples have to be taken very close to the surface it is sometimes easier to snorkel. Here a pair of divers samples blue mussels on a buoy moored in our test-area Nordergründe near the light house Roter Sand in the North Sea.
Fig. 7: To attach the longline to the two piles divers had to install 2 massive steel rings at 5 m depth. The size of the rings can be seen here on the working deck of the RV Uthörn.
Fig. 8: Instruments for AquaLast are attached to the steel rings. The image below shows the underwater data recorder, battery pack, and wave sensor used to measure the force exerted onto the longline. Divers have to service the instruments every two months.