Tuesday 21 February 2017

Long-lived Chaffinch

Hello

Chris Payne spent a couple of hours ringing at Bradden in South Northants today, processing 47 birds made up of a Siskin, 6 Goldfinches, 4 Chaffinches, 23 Blue Tits, 10 Great Tits, 2 Long-tailed Tits and a Nuthatch.

One of the Chaffinches was a male first ringed at Greens Norton in April 2012 when it was aged as an adult. This bird will be at least seven years old this year, pretty exceptional when you think that this species is currently suffering widespread disease issues which is seriously affecting longevity.

Regards

Neil M



Oystercatcher at
Summer Leys.
Courtesy of Robin Gossage.

A nice healthy-looking
male Greenfinch courtesy of
Robin Gossage. This species
is very susceptible to suffering
from a condition called Trichomonosis.
This is a parasite that causes lesions in
the throat of infected birds. They can't feed
or drink and quickly become weak, fluffed
 up and in due course die. One infected bird
 is enough to affect a whole population and
 despite cleaning feeders regularly and below them,
 it is difficult to contain. All finches and sparrows can 
be affected and it occurs in pigeons, doves and
raptors too.

This picture of a male Chaffinch
courtesy of Cathy Ryden shows the early
onset of a crumbly leg disease which
will probably be 'fringilla papillomavirus'
or could be a result of avian pox and/or mite
infestation. Locally up to half of our
Chaffinches suffer from this and in general
the birds learn to cope and can be affected for
years. However the condition will
undoubtedly worsen and it is not uncommon
to see abscesses or 'bumblefoot' take hold.
Toes and claws are lost and it is possible
to see affected birds with just stumps for legs.
However, generally these birds remain healthy
even if towards the end they cannot perch or
hop about! Bullfinches and Yellowhammers can
exhibit similar features, although it is thought they
don't suffer the papillomavirus itself.


A pair of healthy-looking Bullfinches
courtesy of Robin Gossage!

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