Two thirds
of the UK population are in Wales and Llŷn is a very important component, home
to 14% of UK choughs. Numbers in Scotland and Northern Ireland have declined
and Wales is showing signs of decline with a 48% reduction in Snowdonia and
disappearing in Montgomeryshire. In Llanberis there used to be over 65 birds
but now they number just a few. On Llŷn there are between 53 to 60 pairs and
numbers here are starting to reduce. The only habitat where there are signs of increase
is in the sand dunes.
We are
fortunate to have the passion and dedication of Adrienne Stratford and Tony
Cross who have been ringing and recording choughs in mid to north Wales for the
past 23 years. In that time they have ringed 5,000 nestlings, 150 adults and recorded
130,000 sightings. Within Llŷn 1,280 nestlings and 38 adults have been ringed.
Adrienne and
Tony have written a report which hopefully will be published soon. One part of
the analysis records the first year movements from Llŷn showing long distances
of up to 60km – the adults take their youngsters back to the flock or roost
from which they themselves originated.
On average
males travel 10km from their place of birth to where they breed and the females
travel 23km. By spreading themselves out they reduce the risk of in-breeding.
Another
analysis looks into their feeding habits with soil and dung invertebrates a key
component. After breeding and around July the birds head up into the mountains
to feast on bilberries coming back down from August to October to feed on leatherjackets,
the larvae of crane-flies. It’s the cow-pats (and pony-pats) that provide the
best larder during the winter months.
In late
spring I had the privilege of meeting Adrienne in a disused quarry building on
the north Wales coast where last year she’d installed a nesting platform from
bits of old planks.
A pair of
choughs had taken up residence, added heather, lined it with sheeps’ wool and
produced two beautiful chicks. They were plucked from their nest into a pillow
case, brought down a ladder, ringed, sexed and weighed before being returned to
the nest. A couple of times the adults came and shouted insults at us but it
was as if they knew the score; it’s that time of year again. As for the chicks,
they were quite chilled out and happy to beg food with their plaintive cries
and open beaks.
I was
surprised to see the tangerine orange colour of their legs. Eventually these
and the beak will turn to red.
To Adrienne
the choughs are a long running soap opera. She knows their relationships and
family histories and 2 of them are now 19 years old.
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