Northumberland butterfly numbers soar for 2026 as experts warn of 'population crash'

Across the county, 621 people took part, spotting 8,652 butterflies and day-flying moths during the three weeks.

The most-spotted butterfly in the county was the Small White, also known as the 'Cabbage White' due to their caterpillars' taste for cabbages and other brassicas.

The Large White took the second spot, with the Red Admiral following in third.

Another standout species was the Painted Lady – with 584 spotted in Northumberland in this year’s count, contributing to an increase of 335% across the UK.

The strong numbers of butterflies are likely down to excellent conditions for caterpillars in the spring and hot, dry weather which is loved by adult butterflies in the summer.

However, despite conditions being brilliant for butterflies this year, experts warn that what comes next could be dire.

With the Met Office confirming it ‘increasingly likely’ to be the hottest summer on record, August saw more than 70% of England officially declared in drought.

This year, many of the plants that caterpillars depend on had withered or died before the caterpillars had finished feeding on them, and the charity fears the impact on butterfly and moth populations will become fully apparent in 2027.

Professor Richard Fox, Head of Science at Butterfly Conservation, said: “Adult butterflies love hot, sunny weather for flying, feeding and breeding, and that's exactly why people saw so many this summer.

"However, the very same weather that made it a good year for butterflies could mean we’re actually on course for a population crash, which could take years to recover from.”