Standard IWC methodology for multi-disciplinary studies is being used throughout all SO GLOBEC collaborative cruises. This involves experienced cetacean researchers conducting line transect sighting surveys throughout daylight hours in acceptable weather conditions. Data are recorded on a laptop-based tracking program (Wincruz), and photo and video records are also obtained for species identification, group size verification, feeding (and other behavior), ice habitat and individual identification (taken from D.Thiele).
Observations were made from the ice tower by a single observer. When conditions permitted, the observer was outside along the cat-walk of the ice tower, otherwise observations were made from the inside. Effort was focused 45° to port and starboard of the bow ahead of the vessel, while also scanning to cover the full 180°ahead of the vessel. In sea ice, the method was adjusted to include searching behind in the vessel's wake as well, in order that cetaceans and seals hidden by ice would be detected more readily. The observer used a combination of eye and binocular searching (7x50 Fujinon). Effort would commence when the following conditions allowed: appropriate daylight, winds less than 20 kts or Beaufort sea state less than 5-6, visibility greater than 1 nm (measured by the distance a minke whale blow could be seen with the naked eye as judged by the observer) and the ship actually steaming. An incidental watch was kept in borderline conditions or in variable visibility, such as fog and snow squalls. Subjective weather data was recorded to keep track of the changing conditions, e.g., Beaufort sea state, cloud cover, glare, ice, sight ability, etc.
Sightings were recorded on a laptop-based Wincruz Antarctic program, which also logged GPS position, course, ship speed, and a suite of other environmental and sightings conditions automatically. Visual observations were made both during the station-transect portion of the trip, as well as during transit. When possible, photographic and/or video documentation was made of each sighting for later use in individual identification, species confirmation, and habitat description.
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