The Snug Bedding of Tree Sparrows

One of our winter tasks at a nature reserve is checking the bird nestboxes.  Like many winter jobs that take more skill than energy, it’s one of cold fingers and noses, but with rewarding moments.

Some nestboxes may have patches of rotten wood or other damage – this may be caused by poor drainage (especially in poorly designed or badly made boxes), or because the box is quite old.  Now and then there is evidence of woodpeckers or other creatures tapping holes.  Where possible, these are carefully mended, ensuring anyone who takes up residence in the coming year can keep their clutch safe and sound.

The joy of the task comes when a box is found to be full of nesting material – mosses, dried grasses, wool, fur and feathers.  It can be such a very snug, thick wedge of material, all so carefully collected, it is a shame to empty it out.  We must do so, nonetheless, to minimise disease, the likelihood of parasites, and other problems in the old bedding.  The birds will find fresh new material and make their nests cosy again soon enough.

Nesting Material from Tree Sparrow Box at Sun Rising

Nesting Material from Tree Sparrow Box at Sun Rising

This year, 4 of our 6 tree sparrow boxes were found with good nesting material inside, confirming our observation that the boxes were being used by nesting pairs.  The other 2 boxes were damaged and have now been fixed.  If all 6 boxes are used this year, we’ll invest in some more, hoping to increase our population of this little bird. With a conservation status still at RED, it is estimated that its numbers reduced by 93% between 1970 and 2008.  Our little community is a vital part of its revival.

Note the white to beige pheasant feathers in the nesting material in the photograph. You can also see grey feathers, from a wood pigeon or stock dove. It could be that a fox killed onsite at just the right time, when the tree sparrows were collecting for the box.  There are long semiplume and soft down feathers here, ideal for keeping the nest warm and secure.