27-Jun-2006
- A fast-breeding alien fish that has colonised
two East Devon lakes and is threatening to wipe
out the local fish population could soon be facing
extinction itself.
This week the Environment Agency
is taking the first steps to eradicate the Top
Mouth Gudgeon from lakes at Bicton College and
Bicton Park Botanical Gardens near East Budleigh.
By acting now, the Agency aims to prevent any
further spread of the species to surrounding lakes
and rivers.
Measuring only 3 - 4 cms in
length, the Top Mouth Gudgeon can out-compete
native species and may carry a damaging parasite,
both of which could threaten fish diversity in
the area if measures are not taken.
Topmouth gudgeon, a small Asiatic
member of the carp family, appeared in mainland
Europe in the 1960’s. It has been introduced accidentally
into a number of British lakes. This small fish
is around the same size as the UK native gudgeon
which it resembles.
It can out-compete native species
such as roach and rudd because it matures at one
year old, whereas a rudd does not mature sexually
until two or three. It can also breed up to four
times a year.
The Agency recently installed
a gravel filter on behalf of Bicton College to
prevent the spread of the invasive fish. There
was a slight setback after the ornamental lake
overflowed following a thunderstorm and a number
of Top Mouth Gudgeon were washed past the filter
and carried down the Bicton Stream.
Agency fisheries officers later
collected around 6,000 of the fish from the stream
following the thunderstorm ‘break-out’. It is
estimated that there could be up to 100,000 of
the tiny invaders in the smaller lake alone.
On Thursday (June 29) the Agency
will electro-fish approximately 400 – 500 metres
of the Bicton Stream and remove any Top Mouth
Gudgeon it finds. The fish will be sent to the
Agency’s national fisheries experts for analysis.
‘At the moment Bicton is thought
to be the only site in Devon with a population
of Top Mouth Gudgeon. We are keen to take action
to eradicate them. They pose a very real risk
to our native fish. It is important we act now,’
said Dave Brogden for the Environment Agency.
The Agency has successfully
removed the species from two sites in the North
of England and one in the Midlands. Ultimately,
the removal of Top Mouth Gudgeon from Bicton will
probably involve the rescue of native fish from
the lakes prior to final eradication of the alien
species.
Last month special measures
were introduced at Bicton during a BBC Springwatch
event to ensure anyone using the main lake didn’t
accidentally transport Top Mouth Gudgeon fish
or their eggs off the site.
These included using disinfectant
to wash down boats using the lake, cleaning people’s
shoes and boots and cleaning/disinfecting fishing
equipment.
For further information about
the electro-fishing including times, directions
and access arrangements for the site call the
Press Office on 01392 442008.
Note to Editors:
Top Mouth Gudgeon is listed
as a category 5 risk species under the Importation
of Live Fish Act (ILFA) which is the highest level
of risk.
The parasite they carry is believed to interfere
with the breeding cycle of salmon and trout.
The Environment Agency is working with the owners
of the two lakes who have been issued with licences
under the Importation of Live Fish Act (ILFA).
These licences require the containment of the
alien species within the lakes
The smaller of the two Bicton lakes flows into
the Bicton Stream, which feeds the Colaton Raleigh
Stream which in turn flows into the River Otter.
It is thought the Top Mouth Gudgeon were accidentally
introduced to Bicton Lake as a result of fish
stocking.
Mike Dunning
