29/06/2005 - The Environment
Agency has discovered why hundreds of fish
died in Foxcotte Lake in Andover last month.
New research into toxins that can cause damage
to fish has provided a vital clue to the incident.
The Environment Agency was called to the lake
in early June after receiving reports of dead
fish from the Andover Angling Club. Extensive
investigations were carried out and the Environment
Agency considered various possible causes
of death including the occurrence of a pollution
incident or an outbreak of disease.
Water quality samples and autopsies of the
fish were carried out but all investigations
failed to identify the cause of death and
Environment Agency Fisheries Officers were
baffled. However, new research undertaken
by the Environment Agency and Royal Holloway
College has now given Officers valuable information
that has helped identify the most likely cause
of death.
Andy Thomas, Environment Agency Fisheries
Technical Specialist in Hampshire, said: "An
incident like this involving a wide variety
of species is usually due to problems with
water quality and not an outbreak of disease
so our initial investigations focussed on
that possibility. But then we heard about
this new research being carried out by our
colleagues and it has shed some light on the
incident."
To undertake this research, scientists have
been looking at fish gill tissue under powerful
scanning electron microscopes. They have been
able to identify damage that has been caused
to fish by exposure to bacterial exotoxins,
which are naturally produced toxins. The production
of bacterial exotoxins is thought to be linked
to changes in the nutrient status of the water.
Andy Thomas continued: "We carried out
extensive investigations into this incident
but it remained a mystery. Now we have looked
into this research everything suggests that
these toxins are the reason that hundreds
of fish died in Foxcotte Lake."
The Environment Agency, Test Valley Borough
Council and Andover Angling Club have now
met to discuss the findings and what can be
done to minimise the risks of future fish
deaths. Members of the public are advised
that the toxins responsible for the fish deaths
are harmless to other wildlife and humans.
