Looking
like a small parrot, the crossbill is
difficult to confuse with any other British
bird. The male is a reddish colour overall,
the
female yellow-green, both having dark
wings and tail. Juveniles are duller and quite
heavily streaked. Crossbills feed almost
entirely on conifer seeds, and have evolved a
specialised bill to cope with this specialised
diet; the tips of the bill are crossed over,
allowing them to extract the seeds from the
cones of Scots pine and larch etc. A summer
visitor to Britain, every few years an
eruption will occur where crossbills arrive
in far greater numbers, possibly caused by a
shortage of cones in their usual areas. When
these incidents occur the birds often remain
in the country through winter and into the
following summer. Continuing their association
with conifers, crossbills also tend to nest in
them, often in small colonies.
