We provide nesting boxes for birds and plan to add additional nesting boxes for Pipistrelle bats (Pipistrellus spp.), which regularly visit the garden and a male Tawny Owl (Strix aluco) that we have heard calling in the garden for the past few weeks.
We will do this to encourage them to take up residence. It is likely that the limiting factor for both of these species is not the abundance of food but the availability of suitable nesting sites. If we provide suitable nesting sites, they will move into the garden on a permanent basis.
Similarly, if we provide nesting boxes for other species of bird, we encourage them to nest and breed here. Birds are very territorial creatures so we need to be careful as to where we place nesting boxes for the same species. The box in the tree above has an entrance hole 25 millimetres across (1 inch).
This is designed for a Blue Tit (Cyanistes caeruleus).
If we enlarge the hole to 28 millimetres, we attract Great Tits (Parus major).
Isn’t it amazing what a difference 3 millimetres makes?
In contrast, the nest box in the tree overlooking the compost heaps has an open front. This style of box is preferred by Robins (Erithacus rubecula).