UK’s warmest spring boosts songbird breeding: Report

LONDON

The UK’s warmest and sunniest spring on record has led to a rise in breeding success for some of Britain’s best-loved songbirds, according to new data by the British Trust for Ornithology (BTO).

Scientists say the dry and mild conditions in spring 2025 offered a rare boost for threatened wild birds, with higher than average breeding success recorded for 14 species during the May to August breeding season.

Those showing improvements included the chiffchaff, garden warbler, whitethroat sparrow, coal tit, blue tit, great tit and robin.

The findings come from monitoring carried out by volunteer bird ringers for BTO, who tracked 29 songbird species as part of the constant effort sites scheme.

Under the project, birds are caught at the same locations and in the same way throughout the summer each year. This allows scientists to assess changes in adult numbers, the number of young birds produced, and how survival rates compare with previous decades.

Compared with the exceptionally wet spring of 2024, breeding success in 2025 was above average across many species.

Above-average breeding success was recorded among several migratory species, including the chiffchaff, reed warbler, blackcap, garden warbler, and whitethroat.

Among resident birds, nine species – coal tit, blue tit, great tit, Cetti’s warbler, long-tailed tit, robin, dunnock, chaffinch and goldfinch – showed statistically significant increases in breeding success compared with the five-year average.

The report said prolonged periods of good weather may also have increased the likelihood of birds producing second broods, contributing to higher overall productivity.

However, despite the improved breeding results, adult numbers of some popular songbirds continued to fall in 2025, a trend scientists have linked to the poor breeding season the previous year.