UK butterfly season to start earlier than usual

The UK's butterfly season is expected to start earlier than usual due to a particularly sunny spring.

Record-breaking levels of sunshine have encouraged midsummer butterflies to emerge unusually early, with an array of both common and rare species appearing a month before their usual flight season.

Butterflies can be found in meadows and woods in July, including the ringlet and marbled white butterfly.

Image credit: Butterfly Conservation

With weather data indicating this year has provided the best summer for butterflies in nearly 25 years, butterflies have emerged earlier than normal. Most butterflies tend to fly during the warmest, sunniest time of day, from mid-morning to late afternoon.

When the sun comes out, it is typical for butterflies to emerge in large numbers.

Spotted so far is the heath fritillary, a notoriously sedentary butterfly which this year has been found on new sites across Exmoor. Its emergence has come as a nice surprise, particularly as it is listed as an endangered butterfly.

Image credit: Butterfly Conservation

Matthew Oates, a nature conservation advisor for the National Trust, has noted that 10 species of Apatura iris (a beautiful and rare butterfly) has seen 10 species earlier this year than during any other summer for fifty years.

Fortunately for butterflies, they are "climate and weather opportunists par excellence", said Oates. The early emergence of butterflies is an adaptation and response to the early warm dry weather across the UK, but also global warming which is causing large revisions to butterfly flight seasons.