Britain set for butterfly boom after hot spring
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- Prof Richard Fox, head of science at UK charity Butterfly Conservation, said Britain's warm, dry spring and ongoing hot weather could deliver a "bumper summer of butterflies" across gardens and countryside
- Butterflies are cold-blooded creatures that rely on warmth from the sun, so hot, dry days let them find mates and females lay eggs to "create the new generation of butterflies later in the year"
- Fox urged thousands of people to take part in the Big Butterfly Count, recording the number of butterflies seen in a 15-minute window — a handful in a typical garden, "dozens or even hundreds" in flower-rich areas
- Summer 2024 was a "bad year" for butterflies, but Fox said numbers "bounced back" the following year — "not amazing" but improved
- Holly Blue and Red Admiral species had "a really good spring," which Fox said "bodes well for a bumper summer"
- Fox raised a caveat: drought-driven grass die-back and plant wilting could leave caterpillars — the next generation — without enough to eat
Why it matters: Citizen scientists will help determine whether 2026 becomes a banner butterfly season through the Big Butterfly Count, but Fox's caveat matters: the same hot, dry conditions helping adults reproduce are already stressing the plants caterpillars feed on, making the post-summer generation's survival contingent on rain that hasn't arrived.
