The Kiwi Killers;
Slimy invader with huge appetite for earthworms threatens countryside
11/20/2004
The Daily Mail (London, England)
By ALISTAIR MUNRO
An invader from the
other side of the world is threatening to wreak havoc in the Scottish
countryside.
At first glance, the
New Zealand flatworm seems an unlikely enemy, but its enormous appetite for
earthworms make it a huge potential threat to wildlife and agriculture.
Earthworms perform a
vital role, recycling nutrients required by plants and breaking down the
structure of the soil to assist drainage.
The earthworm is
also a part of a delicate food chain for other animals, and its possible
disappearance threatens creatures like moles, badgers and hedgehogs.
Earthworms which
encounter the killer creature literally meet a sticky end.
The flatworm covers
its prey with caustic digestive juices causing it to slowly dissolve.
Estimates suggest
that each of the soaring number of flatworms eat one or two earthworms per
week. Top ecologist Dr Brian Boag yesterday said he believes the earthworm
population is declining rapidly and has called on the Scottish Executive to
urgently provide funding to combat the invader.
Retired Dr Boag, who
used to work for the Scottish Crop Research Institute, said the flatworm poses
a major threat to the livelihood of Scottish farmers.
He claims the true
extent of the dangers which the flatworm presents requires further research,
but minister have refused funding.
'The flatworm was
first recorded in Scotland at the Botanic Gardens in Edinburgh in the 1960s,'
Dr Boag explained.
'It is believed it
came here in the soil of pot plants taken by Botanic Gardens from New Zealand.
'It was initially
considered a curiosity but that status was reviewed in the 1980s when a study
in Northern Ireland showed earthworm numbers were reduced to below detectable
levels. This was as a result of the introduction of flatworms,' he added. 'I
did a study for the Scottish Office in 1992 which showed they were widespread
throughout Scotland.
'Basically they have
spread from garden centres and botanic gardens into domestic gardens. They are
now spreading into agricultural land.
'I get two or three
recorded episodes of flatworm every week.
They are widespread
as Shetland and Lewis. They cover the whole of Scotland.'
Dr Boag added: 'The
population of moles in certain areas has disappeared. I would like to look at
the implications for the rest of wildlife in Scotland.
'If moles are
disappearing because of the flatworm eating their source of food then the
impact may hit badgers and hedgehogs and other animals.
'It would be
negligent of the Executive not to put money towards researching the impact of
flatworms in this country.'
Flat Facts
Officially known as
the earthworm-eater planarian, it has the jawbreaking Latin name Artioposthia
triangulata
It comes from the
Southern Hemisphere city of Christchurch, New Zealand, and arrived in Ireland
and Scotland in the 1960s
The planarian eats
the earthworms which normally help aerate and drain soils and cycle nutrients
It is pointed at
both ends, dark-brown with a pale margin and pale underside.
At rest, it is about
one inch long and 1/3 inch wide - but when moving it can stretch to nearly 12
inches
IT produces shiny black egg 'capsules', each with several young inside. In
its native New Zealand, it probably evolved in beech forests of the Canterbury
Plains
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