At Sea, Falkland Islands to South Georgia
Today is our first day at sea after leaving the Falkland Islands and setting off into the great Southern Ocean. We have been sailing all day on a southeasterly course and will cross the Antarctic Convergence sometime later today. At the Convergence, relatively warm sub-Antarctic waters come into contact with the very cold water flowing north from Antarctica and where the two bodies converge, there is an accumulation of food, which attracts the magnificent seabirds of the Southern Ocean, especially the wandering albatross that have been soaring around the ship all day. There are several other bird species including petrels, prions and tiny diving petrels also in the area.
When we observe albatross from the ship they are nearly always on the wing, although I did manage to photograph one sitting on the water even in a strong breeze (Fig. 3). There is a conventional wisdom that albatross spend their entire lives on the wing and never rest on the surface of the ocean, but his is due to an observational bias resulting from the fact that people usually observe them from ships. The birds know about ships and the chances of a free meal associated with them, especially with fishing vessels, and they will follow ships for miles at sea. To test this conventional wisdom, in 2002 a group of French ornithologists led by Henri Weimerskirch attached miniature GPS tracking devices to free ranging wandering albatross (Diomedea exulans) born on Possession Island in the Crozet archipelago in the southern Indian Ocean. (Science, 15 February 2002). They found that wandering albatross spend 60% of the time sitting on the water and only about 8% of their time flying at their maximum speed flight of about 50 mph. The rest of their time is spent in slower foraging flight.
We are spending our time preparing for our visit to South Georgia by hearing presentations from the natural history staff about the birds, the geology and the waters of the Southern Ocean and by cleaning our backpacks and other foul weather gear so that we do not inadvertently introduce any exotic plants or animals into the relatively pristine environment there.
