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Scientists Tow AUV With Kayak to Protect Coral

Richard Yeo of Hafmynd, Iceland, tows an AUV from a kayak during a wide-swath sonar survey of a delicate coral reef.  The project was the NOAA-funded Bonaire 2008 mission in the Caribbean in January.

Richard Yeo of Hafmynd, Iceland, tows an AUV from a kayak during a wide-swath sonar survey of a delicate coral reef. The project was the NOAA-funded Bonaire 2008 mission in the Caribbean in January.

We believe this is the smallest manned vessel to operate with IHO-quality swath survey equipment, and also the smallest to run with a towfish. Unless someone has seen anything smaller?

In order to protect sensitive coral near Bonaire in Netherlands Antilles in the Caribbean, Richard Yeo surveyed the area by towing an autonomous underwater vehicle (AUV) using a kayak.

The survey was part of a project in January by scientists to map the pristine ocean environment around Bonaire, a shallow leeward environment that was last mapped in the 1980’s by Dutch scientist Dr. Fleur van Duyl.
Yeo’s company, Hafmynd of Iceland developed the Gavia AUV, which uses GeoSwath wide-swath bathymetry sonar, and he was at Bonaire as part of the NOAA Ocean Explorer program Bonaire 2008: Exploring Coral Reef Sustainability with New Technologies.

Usually the Gavia would run autonomously using its own power to follow a pre-programmed mission plan, but operating fully autonomously in very shallow waters resulted in a lot of obstacle warnings and aborted lines, in addition to endangering the delicate coral polyps which reached to 30 centimeters below the surface.

In order to collect the highest resolution data possible, and to investigate how the instruments could be run safely in the shallows, it was decided to tow the unit while it was collecting survey data with the nose camera and sonar.
Yeo ran several 350-meter-long long lines at 1.5kts for an hour and a half through the shallow coral reefs near the Science House.

The bathymetry and sidescan data Yeo collected are now being analyzed for comparison with the van Duyl maps. The data have also been used in the ‘bathycaching’ student exercises during the University of Delaware Study Abroad ‘08 program led by Art Trembanis of the Coastal Sediments, Hydrodynamics, and Engineering Laboratory (CSHEL).

THE MISSION

The Bonaire mission is funded by the US National Oceanic and Atmospheric Administration (NOAA) and aims to enhance knowledge of coral reefs and their value, and to motivate people to take action to sustain them. The work in Bonaire has an especially high profile in 2008, which is the International Year of the Reef. (www.IYOR.org). This expedition was led by Mark Patterson of the Virginia Institute of Marine Science (VIMS), along with co-principal investigators Dr. Arthur Trembanis of the University of Delaware and Jim Leichter and Dale Stokes of the Scripps Institution of Oceanography. Dr. Trembanis has placed an order for a GeoSwath-equipped Gavia for the Coastal Sediments, Hydrodynamics, and Engineering Laboratory (CSHEL) in the College of Marine and Earth Studies at the University of Delaware. As well as the principal investigators and 16 students from Delaware, academics from NOAA’s Undersea Research Center (NURC, USA), the University of British Columbia (Canada), and the National Oceanography Centre Southampton (UK) assisted the mission.

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