Saturday, 28 January 2017

Spain 16: Wallcreeper!

One of the most sought after birds in the mountains of Europe is the Wallcreeper, Tichodroma muraria. This relative of the nuthatches has a vast range from the Pyrenees across every mountain range in Europe and Asia to Eastern China in the breeding season. Outside the breeding season they spread more widely and to lower levels, with one even wintering in the Cheddar gorge not far from Bristol here in the UK in two separate years in the 1970’s.

Wallcreeper - range
In the summer Wallcreepers are found in the high mountains mostly above the tree line where they feed by gleaning insects and spiders brought from lower levels by the updrafts along the cliff face. Favoured locations are areas with overhangs and crevices, especially near water, as these usually have more invertebrate prey. Wintering sites may be more level and even include buildings in cities – one wintered in Amsterdam in 1990 – or quarries. In all cases there is little plant cover and large areas of bare rock and earth.
Wallcreeper in India
They are quite territorial birds at all seasons, and a given wintering site usually only has a single bird at a time. We found ours at a dam in the Pyrenees. The autumn had been mild, so we were a little concerned that the wintering birds were still on their breeding sites, but after a lot of searching we managed to locate one at last. They are surprisingly hard to spot as their blue grey colouration is a pretty good match for grey limestone, especially in the shadow of an overhang. They hunt over the rock face in the same way a nuthatch does over a tree, occasionally flying out to catch an insect in mid-air or flying from one side of a gorge to another.

When breeding the female constructs a cup-shaped nest deep in a crevice or cave where it is protected from the winds. Four or Five eggs are laid and incubated for around 20 days. The young fledge after around 28 days. Given the short breeding season at altitude there is only time for a single brood.

Film of Wallcreeper here:

Given the vast range of the Wallcreeper it is classed as Least Concern by the IUCN. There is little chance of the status changing as its habitat is unlikely to be altered by human beings or changes in agriculture.

(images from Wikipedia)

No comments:

Post a Comment