Alastair Christie, the Island’s Asian hornet co-ordinator, said the number found this time last year was around four.
Thirteen active primary nests, with queens inside, have been located and destroyed, compared to 12 nests last year, he added.
Last month Mr Christie began the fourth year of a battle to contain the spread of the Asian hornet, working with the Natural Environment Department.
‘The amount of queen Asian hornet sightings has dramatically increased, while the amount of nests found this year is no different to last year,’ he said.
Although the rise is a concern, Mr Christie said he thought that people were now much more aware of the issue. ‘A lot of people are on high alert, which means the amount of reports is much higher than last year,’ he said.
‘So far we have had a total of 203 reported sightings of Asian hornets and of those, just 80 turned out to be a hornet – the rest were just wasps, bees and other pollinating insects.
‘But while the increased amount of sightings is partly down to people being more aware, it is also undoubtedly due to the fact that there are more of them on the Island this year.’
Mr Christie, who was previously on the Jersey Beekeepers’ Association’s management committee, was this year tasked with leading a new strategy, called the Asian Hornet Management Plan.
The plan includes slowing the rate of the species’ spread and funding the destruction of nests by professional pest controllers by providing specialist equipment, materials, training and advice. The strategy will also aim to ensure Islanders are aware of Asian hornets and the risks that they pose.
The insect is native to parts of eastern Asia and was accidentally introduced to south-west France in 2004. It went on to reach the Channel Islands and the UK in 2016.
The rise in the number of nests found in Jersey indicates a rapid rate of establishment and 2019 could see a further increase in numbers, according to the management plan.
Asian hornets are threat to local wildlife and can consume up to 50 honey bees in single day.