ALONG with scores of Islanders, one of the UK’s most endangered insects will be enjoying the dulcet sounds of the National Trust for Jersey’s Sunset Concerts later this month at Grantez.
The former parking area used for the events was discovered to be the best habitat in the Island for Gryllus campestris, more commonly known as the field cricket.
While the gigs were on break because of the pandemic restrictions, the site was among a number surveyed last year during the cricket’s May and June breeding season. To figure out how many field crickets called each site home, the surveyors listened for the insect’s distinct songs.
After determining Monts Grantez, above St Ouen’s Bay, had the most activity, a more intense survey was undertaken with the help of the Société Jersiaise’s entomology section and 142 singing males were recorded and mapped across the site.
Adult field crickets range in size from 17mm – 26mm. They are described as a ‘chunky’ species with black or brown bodies and yellow wing bases.
The male insect digs a burrow during mating season and ‘sings’ to attract a mate. Although they have wings, field crickets cannot fly, and instead use them to create loud chirping, mating calls.
National Trust for Jersey conservation officer Louise Whale told the JEP that field crickets were among eight insects listed as protected wild animals under the Jersey Wildlife Law enacted last year.
‘Since then, we have had to relocate our car park for the Sunset Concerts due to the high numbers of crickets being present at the old car park sites,’ she said.
‘While this may mean that there will be less parking available for the concerts this year, we hope that our supporters understand that we want to enhance our local biodiversity and feel encouraged to make use of public transport.’
The trust will also be putting up signs around Grantez to raise awareness about field crickets and their precarious future.
The concerts are not expected to disturb the insects.
‘There is no current evidence to suggest that the Sunset Concerts negatively impact their population numbers,’ said Ms Whale. ‘However, we will be monitoring the cricket numbers for several years and adjust our plans if something changes.’
The site has been grazed by sheep since 2004, she added, which has helped prevent the domination of bracken.
‘According to Mike Edwards, from Bees, Wasps and Ants Recording Society, who we have been working closely with, the lack of suitable habitat management is one of the leading causes of decline for the field cricket, which shows how vital our work at Grantez is,’ Ms Whale said.
The crickets find an ideal habitat in the early dry grassland at Grantez. ‘If too much scrub – shrubs and young trees – takes over the grassland, the crickets will find this less attractive,’ Ms Whale added.
‘While scrub is still valuable habitat for other species, it must be carefully managed to make sure a range of habitats can also thrive.’
To avoid harming the crickets or damaging their burrows, visitors to Grantez are encouraged to stick to the footpaths in the area.
‘If the crickets are given space, you can enjoy watching their natural behaviour with the best time to see them being afternoons or evenings during May or June,’ Ms Whale said. ‘As with any species, it is always a great idea to take a photo when you see one and send it to the Jersey Biodiversity Centre or enter it into the iRecord app.’
