By ANNE BESTON
Seals with video cameras attached to their heads are being used to unravel some of the mysteries of life under the Antarctic ice shelf.
Over the past three summers, a team of researchers from three American universities set up base at McMurdo Station and attached video cameras and
data recorders to 15 Weddell seals.
The original aim of the project was to observe seal hunting behaviour but the scientists have found the "sealcams" have also shed light on the behaviour of two rare Southern Ocean fish species hunted by the Weddell seal and prized by commercial fishers - Antarctic silverfish and Antarctic toothfish.
The cameras and data recorders allowed the scientists to accompany the seals on their hunts and to record how the seals and their prey interacted.
The study gave the scientists more data on species distribution.
Most silverfish were observed at depths greater than 160m, with some swimming at low as 414m. Toothfish were generally found at about 180m.
Based on the sealcam data, the researchers believe silverfish migrate from deeper to shallower water using reflected light as a cue, even without the benefit of sunset during the Antarctic summer.
The researchers acknowledged the limitations of using the sealcam but said improved technology could mean similar techniques could be used to observe species such as dolphins and small whales in their natural environment.
The team will publish its findings in Marine Biology journal next month.
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