For three weeks from mid-July, 126 Islanders recorded a total of 2,223 sightings of butterflies and moths as part of wildlife charity Butterfly Conservation UK’s Big Butterfly Count. The figure represented a 30% drop from the 3,182 recorded in 2019.
A similar decline (34%) was recorded over the same period across the remainder of the British Isles by more than 111,500 volunteers, giving further concern for the future of the insects that play an important role in the human food chain by pollinating crops.
Overall, the nationwide results were the lowest average number of butterflies logged since the event began 11 years ago, despite more members of the public taking part than ever before.
Dr Zoë Randle, senior surveys officer for Butterfly Conservation, said: ‘Unfortunately, this summer has not seen an abundance of butterflies across the UK. We do see peaks and troughs of butterfly numbers each year – last year for example we saw a huge influx of migrant painted lady butterflies – so the data from the Big Butterfly Count is an important snapshot which, along with our other monitoring schemes, helps our understanding of the rates of decline of butterflies and moths.’
However, it may not be all bad news for Jersey’s butterflies, as a more detailed picture of how they are faring will be available early next year when the findings of the separate 2020 local annual Butterfly Monitoring Scheme are due to be published.
Denise McGowan, who works for the Island’s Natural Environment team and oversees the Jersey Butterfly Monitoring Scheme, said: ‘At this stage it is not clear why there was a decline in butterfly sightings for this year’s Big Butterfly Count.
‘Butterfly Conservation states that it may be due to an early spring resulting in butterflies appearing earlier and the count only capturing the end of the flight period for some species.
‘We are pleased that more people took part in the Big Butterfly Count this year. We value people’s time and effort when they take part in these surveys. We also know that they learn through getting involved and they are contributing to a large-scale project.
‘They also get the feel-good factor of being outdoors in nature, something that is especially important this year.’
Since 2004, 50 Islanders have volunteered for the local monitoring scheme to record butterflies at 33 sites – known as transects – around the Island once a week between April and October when butterflies are active.
Top ten Jersey butterflies in the Big Butterfly Count 2020
1. Large White
2. Gatekeeper
3. Red Admiral
4. Speckled Wood
5. Small White
6. Meadow Brown
7. Common Blue
8. Small Copper
9. Small Tortoiseshell
10. Painted Lady
