The message
from "Geoff" contains these words:


I don't know anything about birds, the bad one was black with a red
crest and a longish beak,

Most woodpeckers have red feathers on the head but if, as you say, the bird
was black then it might have been a dyocopus martius a.k.a. a black
woodpecker but they are almost as large as a crow and have not been
recorded
in Britain. Stand by for twitchers?!!

My guess is that it was either a great spotted woodpecker (picoides major)
which also has a red bum or a lesser spotted woodpecker (picoides minor)
having no red bum! Both these are fairly common and the former has a
penchant for bluetits' peanuts so it might be an idea to move any peanut
dispenser far away from any nest box.

Actually Lesser Spotted Woodpeckers have become quite rare and are now
on the Red List of species in serious decline.

Judith's bird is almost certainly Great Spotted Woodpecker as they are
common in gardens and behave in just the way she describes.

Janet G