Wild animals see overhead electrical powerlines as disturbing lines of flashing lights, which could explain why many species avoid electricity pylons to the point where their natural territories become seriously fragmented, scientists have discovered.
A study of wild reindeer in Norway has shown that they can see overhead power lines in the dark because their eyes are sensitive to the flashes of ultraviolet light which are invisible to the human eye but are constantly being emitted by high-voltage electrical transmission, the researchers said.
Many other species, from birds in the Arctic to elephants in Africa, can also see ultraviolet radiation which may explain why different kinds of animals in widely varying habitats all tend to avoid overhead power lines even though they are considered to be inert and invisible to wildlife, they said.
“Reindeer see deep into the UV range because the Arctic is especially rich in UV light. Insulators on power lines give off flashes of UV light,” Professor Jeffery said. “The animals potentially see not just a few flashes but a line of flashes extending right across the horizon. This is the first bit of evidence that explains why we think they are avoiding power lines,” he said.
Scientists have known that many animals avoid power lines to the point that it sometimes causes their populations to fragment into separate habitats. But until now the observation could not be easily explained, especially as the avoidance goes on for many decades after the power lines were first erected.
Source: Powerlines disturb animal habitats by appearing as disturbing flashes of UV light invisible to the human eye The Indepedent (12/03/14)
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