Can wasps help save Britain's conker trees
Can wasps help save Britain's conker treesWasps, regarded by many as a pest, could be the salvation of Britain's
imperilled conker trees currently under threat by an 'alien' species of moth.
The horse chestnut leaf miner is an 'alien' (non-native) moth which arrived in
the UK in 2002 and is rapidly spreading damage across the country's conker
trees. Now, academics from the Universities of Hull and Bristol have teamed up
with thousands of children across the country as part of a national Conker Tree
Science project and are asking for the public's help to see how successful wasps
are at attacking the moths.
The moth has caterpillars that live inside conker tree leaves, forming
distinctive patches of damage called 'leaf mines'. Up to 700 leaf mines have
been recorded on a single leaf and the damage caused by large numbers of larvae
can be striking.
Severely damaged leaves shrivel and turn brown by mid summer and fall early,
well before the autumn, giving the impression that the tree is dead. Although
the moths do not kill the trees directly it appears that they weaken the trees,
which then produce smaller conkers and may become more susceptible to lethal
diseases.
These moths are attacked by tiny parasitic wasps - related to the familiar
large, striped wasps - which act as natural pest controllers in the British
countryside.
No one knows how successful these wasps are at keeping moth numbers down so Dr
Darren Evans and Dr Michael Pocock are inviting schools and members of the
public to take part in an exciting national web-based experiment to look at the
rate of attack as well as monitoring the rate of spread of this 'alien' insect.
This is the largest project of its kind in the UK and is funded by the Natural
Environment Research Council (NERC).
Dr Darren Evans from the University of Hull, explains: "We are asking
schoolchildren and members of the public to be our 'lab assistants'. Parasitic
wasps are vital pest controllers not only against these 'alien' moths attacking
conker trees, but also for garden and farm insect pests. This is a real
scientific study - we don't know the answer, but we are excited to see the
results."
Dr Michael Pocock from the University of Bristol, added: "We need more help to
fully understand how important these wasps are, and so we are asking any member
of the public to get involved - all you need is a conker tree with the 'alien'
leaf-mining moth. Pick a leaf this week, put it in a plastic bag and see what
insects come out in two weeks time. It's an easy, but important way to add to
scientific knowledge."
There are several thousand species of parasitic wasps in the British
countryside, which provide a beneficial service to people by controlling insect
pests.
Dr Evans and Dr Pocock recently ran a pilot study in Bristol city centre to
raise awareness about the effect of alien species on biodiversity; they used a
large Jenga game to demonstrate that we rely on nature and the fact that once
enough animals and plants are taken away, there can be a catastrophic effect on
people.
Dr Evans continues: "Any alien species is a major threat to biodiversity because
all organisms live in relation to each other and once an imbalance occurs, the
whole system could begin to unravel. The horse chestnut leaf miner is just one
example of how destructive an alien species can be."
To find out more and to take part in this important experiment visit
www.ourweboflife.org.uk <http://www.ourweboflife.org.uk>
