Southern Small White butterfly in UK spotted for the first time
For the first time, the Southern Small White butterfly in UK has been officially recorded. A volunteer at Landguard Bird Observatory in Suffolk photographed the butterfly on 2 August, marking a historic arrival for this species previously confined to warmer regions of Europe.
Southern Small White butterfly expanding its range across Europe
Once limited to southern and south-eastern Europe, the butterfly has been steadily extending its territory northward over recent decades. It was first noticed north of the Alps in France and Germany in 2008, reached the Netherlands in 2015, and was recorded in Calais by 2019.
Experts believe climate change has played a major role in its expansion. However, early models published in the Climatic Risk Atlas of European Butterflies (2008) suggested the species would not appear in northern Europe until after 2050, even under severe warming scenarios. Its arrival far earlier than expected has surprised many conservationists.
Key identification features
The Southern Small White can be distinguished from the more common Small White butterfly. Its dark spot on the edge of the forewing extends lower, aligning with the circular spot further down. This subtle difference allows experts to confirm sightings with accuracy.
An “ecological leap” northward
Dr Dan Hoare, Director of Nature Recovery at Butterfly Conservation, described the butterfly’s arrival as an “ecological leap.”
“Southern Small White has spread rapidly, colonising regions from the Swiss Alps to the North Sea within a decade. It has moved north at nearly 100 kilometres a year—an extraordinary pace,” he explained.
This rapid movement sets it apart from other butterflies occasionally blown into the UK, which do not represent broader ecological shifts.
Will it become a resident species?
Whether the Southern Small White butterfly in UK establishes a long-term presence remains uncertain. Its caterpillars feed primarily on Candytuft, a garden plant that is not widely grown across Britain. Without an abundant food source, the species may not be able to sustain breeding populations.
At present, the sighting is considered a remarkable one-off record rather than proof of colonisation. Unlike migratory species, the Southern Small White has never previously travelled to the UK and has not yet been observed reproducing here.
