I am planning to put up some nesting boxes for sparrows. I believe they are "colony" birds which means they are more likely to occupy the boxes if there are several close together.
Is this true and if so should you put them right together in a line or in a diagonal pattern or space them out a bit (or does it matter? )
Also, is it best to leave them completely empty or put a bit of bedding in?
(I put up 2 nesting boxes for blue tits a few years ago and they don't nest in them anymore although they did for two or three years)
Any advice would be appreciated
Don't be disappointed if nothing nests in them for a while though. Nearly all birds have nested now and are busy kitting out their nurseries with soft furnishings. Some have young already.
We have sparrows along the length of our back wall under the tiles and yes they live in colonies. Get the boxes up now and they will be weathered in well for next spring.
I saw some communal, sparrow boxes in a garden centre just the other day, about 3 or 4 joined together, I think, so they should be, hopefully, easily available.
I think, cleaning out the boxes in the autumn is a good tip.
Sparrows may be gregarious but still want their own space when breeding. It is unlikely that two pairs will get along with closely placed nest boxes.
The shape/size for sparrows is immaterial - they will breed in anything. As long as they feel safe, they will breed. Watch out for places where predators could jump or reach the nestbox.