Richard Collins: Disappearing garden birds caused by an ancient parasite

There are fewer chaffinches and goldfinches these days — and greenfinches seem to have suffered greatly

Our European Greenfinch (Carduelis chloris) population has suffered a dramatic decline, caused by Trichomonas gallinae (the avian equivalent of Black Death)

Hail to Thee, far above the rest

In joy of voice and pinion,