During the People’s Walk for Wildlife and the rewilding conference in Cambridge last year, I learnt in disbelief about the dramatic declines in insect, bird, mammal and wild plant populations since the 1970s – the decade in which I was born. This year I have resolved to put nature at the heart of our garden in an effort to support the natural world in my small piece of over 400,000 hectares of gardens across the UK – a collective habitat with the potential to make a real difference for wildlife.
We already feed the birds and have nestboxes; we grow plants for pollinating insects and garden organically without peat. So I am beginning to look for more ways to make our garden accessible and welcoming for wild creatures. We are currently adding a range of nestboxes for different species of birds to the small hole boxes we already have, and there are plans to install a barrel pond, create a small wild flower lawn, build hedgehog habitat beneath log piles and monitor the garden birds, amphibians, mammals, mini-beasts and wildflowers throughout the year.
In early March there’s still time to put up nestboxes before the breeding season is in full swing, so this seems like a good place to start. I hope you’ll join me throughout the year, as we encourage as much wildlife into our modest-sized garden as possible.
What nestbox where?
When putting up nestboxes, it is important to ensure they do not get overheated during warmer weather. Unless they are sited in good shade, it is best to site them on a wall or tree, facing between north and east, so that they are protected from the sun for much of the day. Unless otherwise stated, it is advisable to fit them at least 1.5 – 2m above the ground. It is also worth remembering to put them out of reach of neighbouring cats.
As a general rule, it is best to avoid the “decorative” nestboxes frequently seen in garden centres and some craft shops; they are often too small and may have the hole too close to the floor of the box (a distance of at least 120mm is recommended).
Small Hole Nestbox
This traditional nestbox is frequently used by Blue Tits and Great Tits, depending on the size of the hole (Great Tits need a hole with a minimum diameter of 28mm, while Blue Tits can fit through a 25mm hole). If you are lucky enough to have Coal Tits in your garden, they will also sometimes use artificial nest sites (again, a 25mm hole is big enough for them).
We’ve had both great and blue tits nesting in the small hole boxes in the garden
House Sparrow Terrace
House Sparrows generally nest in small colonies and will readily accept boxes if there are several close together. For this reason, many wildlife product suppliers offer “House Sparrow Terraces”, which usually take the form of a long box with 3 separate compartments. However, the same effect can be achieved by placing three, or more, boxes in close proximity to one another. Being somewhat bigger than Great Tits, House Sparrows need an entrance hole of at least 32mm diameter. Boxes should be at least 2m above the ground and, preferably, somewhere that is not subject to too much human disturbance.
Medium Hole Nestbox
Starlings typically nest in holes in trees or under roofing tiles if they can get access. They happily accept nestboxes but need more space than smaller species, so use a slightly larger box with an entrance hole of 45mm. Boxes should be placed at least 2.5m off the ground.
These boxes are aimed primarily at Robins although will sometimes be used by Wrens. Being open-fronted, they are more susceptible to predation than conventional nestboxes and should be placed in a well concealed site such as under overhanging ivy or clematis. Height off the ground is unimportant although, again, it is best to try to keep them out of reach of the local cats.
Swifts and House Martins
Swifts have declined as a breeding species in Britain as many older buildings with access to the eaves have been demolished and new houses do not usually offer any access. Specially designed Swift boxes can be put up under the eaves of your house but it might be necessary to play Swift calls throughout the summer months to attract them to the site. Artificial nests for House Martins are also available and can be fixed under the eaves.
Many species will not nest in boxes. Some that will, but are less likely to be encountered in most gardens are listed below:
If you live somewhere that has any of these species and would like to try to get them to nest in your garden, I would recommend “The BTO Nestbox Guide” by Chris du Feu, an excellent publication, with details of a wide range of nestboxes. Good quality nestboxes can be bought from the RSPB, CJ Wildlife, Ark Wildlife and other reputable wildlife equipment providers.
If you have a nestbox in your garden, why not take part in the British Trust for Ornithology’s “Nestbox Challenge”. They provide guidance on how to monitor nesting birds safely, without causing them to desert their eggs or chicks.
With thanks to bird guru, Alan Garner, aka my generous, talented and fabulous dad! If you’d like to follow our garden rewilding this year, just click below to subscribe.
4 thoughts on “What Nestbox Where?”
I’ve always wanted to know the hole sizes that different species prefer. Thanks Alan and Nicola for getting all the info together in one place!
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Really glad you found it useful – hope you get lots of birds in the garden this year!
A really interesting and informative post. Great!
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Thank you – really glad you found it helpful. Wishing you a bird-filled spring garden!
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