This piece from a London newspaper yesterday dovetails with the current
thread about the incremental demise of bustards and other birds here in
Australia. It isn't pleasant reading, but it is so relevant to us and our
problems that I feel the need to share it.
Bill Jolly
Irish barn owl faces extinction as numbers dip
A study has shown a catastrophic decline in the number found in the country,
indicating the rare species may not survive. The census found just 150
breeding pairs of barn owls, compared with almost 500 in 1972.
"I think we are going to lose them," said Dick Coombes, a conservationist
who works with BirdWatch Ireland. "Their numbers have fallen below the
critical mass."
The decline is due mostly to poisoning and a lack of suitable nesting sites
and hunting grounds.
Dominic Berridge, an ornithologist, spent three years counting owls and
collating information on their nesting sites. His unpublished report
concludes that they are now close to extinction.
"Barn owls have virtually vanished. Only a handful have survived west of the
Shannon. The rest live around Dublin, Wexford, Meath and Louth, with a
smaller population in Cork," he said.
"Poisons are causing most deaths. Owls are killing and eating poisoned rats.
All vermin poisons, with the exception of warfarin, kill owls."
Berridge's study also found that it was becoming increasingly difficult for
owls to rear their young.
"Traditionally, they bred in old buildings. These days, there are few stone
buildings that have not been developed and most modern grain sheds have no
access for owls," he said.
Barn owls will nest in hollow trees but these are often chopped down by
landowners for insurance reasons. A lack of suitable hunting grounds and
prey has also contributed to their decline. "Irish owls feed predominantly
on field mice. Before the 1960s many farm yards were alive with mice and
rats. This is not the case anymore," said Berridge.
In Britain, the species feed largely on field voles, but they do not exist
here. The fact that little is known about the owls' hunting methods makes it
difficult to preserve them.
"We are not sure how barn owls hunt - whether they hover, pounce or hop from
post to post. Tilled fields seemed to help," said Berridge.
Coombes believes it is probably too late to save the barn owl. "A pair will
occupy a territory three kilometres wide," he said. "If one birds gets
poisoned, its mate becomes redundant immediately because the chances are it
will not find another suitable mate.
"The big decline happened in the last 20 years. I remember owls flying
across to Dalkey island to hunt rats but they have now gone," he said.
The release of owls bred in captivity has been tried in Britain with little
success. "If wild owls cannot survive there is an underlying problem that
needs to be addressed through conservation measures," said Berridge.
"Releasing captive birds will not solve the problem."
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