Dirty bird tables wiping out greenfinches

GREENFINCH numbers have plummeted due to a parasite found on dirty bird tables, with conservationists sounding a high-level alert over the birds’ future.

There was no fear for the species when the UK’S list of endangered birds was last updated in 2015. But now it faces being moved straight to the “red list” – indicating species of greatest concern – should the decline continue at the current rate. Numbers have plunged by 59 per cent in just 10 years, and the British Trust for Ornithology has now issued a major warning.

Dr Dario Massimino, lead author of the trust’s Birdtrends report, said: “Greenfinch abundance fluctuated somewhat up to the mid 1990s, but there was little change in either survival or breeding performance during this period. More recent CBC/BBS (Common Birds Census/breeding Birds Survey) data indicates population increases widely across the UK, followed by a sudden sharp fall induced by a widespread and severe outbreak of trichomonosis, which affects the upper digestive tract, that began in 2005.”

Trichomonosis makes birds’ throats swell, meaning they starve to death. It is spread by dirty bird tables, so householders are urged to clean them.

The parasite that causes the disease has long been known in pigeons and doves, and somehow spread to finches.