A programme to recruit the public in monitoring the horse chestnut leaf miner moth (Cameraria ohridella) has led to greater understanding of the pest's establishment in new areas.
Researchers Michael Pocock of the Centre for Ecology & Hydrology and Darren Evans of the University of Hull recruited around 3,500 people to the Conker Tree Science project in 2010.
The data they submitted confirmed that
- levels of damage to horse chestnut leaves were greatest where C. ohridella had been present the longest;
- the level of attack C. ohridella by parasitoids were also greatest where it had been present the longest.
"There was a rapid rise in leaf damage during the first three years that C. ohridella was present and only a slight rise thereafter," the researchers deduced from the data.
Meanwhile, rates of parasitism increased from 1.6 to 5.9 per cent between the third and sixth years of its establishment.
They added: "We suggest that this increase is due to recruitment of native generalist parasitoids, rather than the adaptation or host-tracking of more specialized parasitoids, as appears to have occurred elsewhere in Europe."
Public participants tended to under-report parasitoid activity compared with experts, which was accounted for in the analysis, they added.
On the practical value of the approach, they concluded: "With appropriate checks for data quality, and statistically correcting for biases where necessary, hypothesis-led citizen science is a potentially powerful tool for carrying out scientific research across large spatial scales while simultaneously engaging many people with science."