Updated: 12 September 2012
Four different “ecotypes” of killer whales spotted in Falklands waters
Ten different “ecotypes” of killer whales have now been proposed: populations that look different, have different prey preferences, feeding habits and acoustic behaviours. Also they may represent several different species.
Cataloguing photos from around the world, biologists have identified five different ecotypes in each of the Northern and Southern Hemispheres, with possibly as many as four having a distribution that could potentially include waters around the Falkland Islands.
At Sea Lion Island, “type A” killer whales are sighted. These are clearly demarcated black and white, with a white patch above and behind the eye. However, there are likely to be other ecotypes in Falkland waters. The “type D” killer whale has just a tiny white eye patch; it is known from a few sightings in Sub-Antarctic waters, including at South Georgia and it probably occurs in Falklands waters also.
A pod of killer whales photographed to the north of the Falklands in 1979 has now been identified as “type B” killer whales; more grey than black and with a much larger white eye patch than types A or D. And from satellite tracking studies, there is reason to suspect that this form regularly moves through the waters offshore the Falklands.
Eight type B killer whales foraging in Antarctic Peninsula waters were equipped with satellite transmitters to record their movements during the summers of 2010-2012 by US scientists John Durban and Bob Pitman.
To the scientists great surprise, these killer whales made speedy northwards trips, getting up to speeds of 12km/hr or 6.5 knots, passing just east of the Falkland Islands, to the much warmer waters off Uruguay and Brazil.
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