杏吧原创

NEXT time you hear someone say last night鈥檚 TV was so bad they lost the will
to live, spare a thought for Australia鈥檚 urban possums. For them, TV really can
be fatal. Cable TV lines strung from the poles that carry electric power lines,
rather than buried underground, have proved an unexpected threat to wildlife,
say researchers at Deakin University in Melbourne.

Emily Seymour and Peter Brown in the university鈥檚 school of ecology and
environment have found that possums are being electrocuted. The problem stems
from the cable companies鈥� decision to run their electrically neutral cable TV
lines above the electric power lines.

Power companies cut back trees near power poles to stop possums jumping onto
the live wires. But the optical fibres used for cable TV lines are safe to climb
on and branch off in different directions, giving possums new routes to clamber
onto the lines, Brown says.

While the animals are sitting on the cable TV lines they鈥檙e safe. The danger
comes when their prehensile tails grasp nearby power lines, electrocuting them.
This not only kills the animal, but often causes a local power cut. 鈥淭he optical
cable enables brushtail possums ready access to power lines, but the lion鈥檚
share of the outages are caused by the smaller ringtail possum,鈥� says Brown.

The researchers have assessed the cost to power companies of these power cuts
since the cable lines were first installed in the 1990s. 鈥淪ince the cable TV
rollout, there鈥檚 been a doubling of wildlife-caused outages,鈥� Brown says. 鈥淣o
one considered urban wildlife at all when they decided to run cable TV on power
lines.鈥� Melbourne power company United Energy, for example, lost A$5.7
million (拢2.2 million) between 1994 and 1998 due to wildlife-caused power
cuts, most of them thanks to possums. The utility is now insulating its live
wires to save money鈥攁nd possums.

鈥淭he ringtail possum might be considered a pest by some members of the
public, but we should still be conserving them,鈥� says a spokeswoman for the
World Wide Fund for Nature.