25 JUNE 2019

What birds use bird boxes

There're are up to 22 birds in the UK that use bird boxes, with the entrance hole size and shape important, and where the nest box is located.

Common birds in Britain that use bird boxes largely extends to small garden birds only; Tits, Sparrows, Robins and Wrens. With box options for larger birds that frequent the woods rather than busy urban areas; Owls, Kestrel, Nuthatch, Stock Dove and Woodpeckers likely to take to a box.

If you're thinking about setting up a bird box in your garden its likely you'll have one of the most common garden birds setting up home in the wooden box.

Well Wrens and Robins prefer an open fronted box, Tits and Sparrows prefer a box with a small rounded entrance hole, measuring anywhere from 25mm to 28mm.

Location is important, and well Blue Tits, Coal Tits and Great Tits would be happy to setup anywhere, Robins and Wrens demand seclusions with the box sited behind vegetation.

Talking about siting a bird box in the garden, make it so its facing north/east as to keep it away from direct sunlight and harsh westerly winds.

Which way you face a bird box is vital to keep the occupants safe during nesting times.

Well most birds will nest in a box setup in the garden, there's also the birds that will only take to boxes setup in a tree, preferably in a wooded area.

Bird Box Type Table

Bird:	Hole Size:	Type:
Barn Owl	120mm	Box
Blackbird	130mm	Open Fronted Box
Blue Tit	25mm	Box
Coal Tit	25mm	Box
Great Tit	28mm	Box
House Martin	45mm	Half Cup
House Sparrow	28mm	Box
Jackdaw	120mm x 120mm	Box
Kestrel	120mm	square
Marsh Tits	25mm	Box
Nuthatch	32mm	round
Pied Flycatchers	28mm	round
Pied Wagtail	100mm high	round
Robin	100mm high	Open Fronted Box
Starling	45mm	Box
Spotted Flycatcher	60mm high	Box
Stock Doves	120mm	Box
Swifts	28mm x 65mm	Half Cup
Tawny Owl	270mm - 230mm	Box
Tree Sparrow	28mm	Box
Woodpecker	45mm	Box
Wren	140mm	Open Fronted Box

Blue Tit

Blue Tits love handcrafted bird boxes as the only bird that would take to them over all other Tits, including most other species.

If there is a picture of a bird using a bird box, you can bet anything the Blue Tit is occupying it - usually confirmed as it protrudes through the entrance hole.

Opportunity that comes from selecting a bird box for a Blue Tits is endless, with all small entrance hole boxes suitable.

With that, you can use a box with a 25mm hole but it would be ideal for most other Tits.

Coal Tit

What is good for a Blue Tit is almost good for a Coal Tit, but would require the smallest hole at all times.

Multi-use bird boxes with a 25mm option entrance hole is a start, but make it one that is absolutely accurate to prevent others from nesting.

Again, what you select for a Blue Tit would be a perfect fit for a Coal Tit, so don't be surprised if you get a Blue or Marsh nesting in the box instead.

Great Tit

Of all the Tits, the Great Tit requires a box that is everything that is identical to all other bird boxes for Tits, only it requires a 28mm entrance hole as oppose to 25mm.

As its says in the name Great, so therefore this is an indicator of a larger bird, but not much bigger and still within the Tit family.

Internal dimensions are usually kept the same well only the hole needed enlarging.

If you're regularly visited by Tits, the Great is less likely to nest over others.

Wren

The Wren will take to a bird box that is actually designed for Robins, with a rectangular entrance hole with a fairly large gap overall.

Wren bird boxes are not really available to buy, as focus is on Robins only.

If you want to attract Wrens to nest use a Robin bird box that is smaller, stumpier and has a shorter distance from the entrance hole to the floor of the box.

Setting up a Wren box is made more difficult as it needs to be hidden behind plantation.

Robin

Note that you'll never get a Robin to nest in a bird box with a standard round entrance hole, with anything from 25mm all the way up to 45mm hole not suitable.

Instead the Robin bird box requires an entrance hole that is large and rectangular, or more into a square shape if that's what you have, depending on the manufacturer.

Saying that, the Robin would also take to more fancier boxes with a unique entrance, including that of a log/natural box with a more rounded but still large hole.

This might all be a moot point though as bird boxes for Robins need to be hidden below 2 metres well hidden in vegetation, so you might not see it.

Blackbird

Much like a bird box designed specifically for a Robin or Wren, the Blackbird uses an open-fronted bird box but with a change of style.

Rather than the Blackbird nesting in a confined wooden bird box, the open front is far larger, while opening up around the sides.

To see a Blackbird use a bird box of this type would relate to what they build in nature, only the wooden box is far safer to use.

Opening can vary in height or width drastically with little to no effect on potential occupants, but to make it an 130mm high open front at least would be a good start.

House Sparrow

If you're thinking about setting up a nest box for use by a Sparrow, know that House Sparrows require a colony box.

By that we mean multiple bird boxes lined up side-by-side, or a single box with up to three compartment.

House Sparrows don't nest alone but instead require nearby Sparrows as they are colonial nesters.

Your option to buy a bird box for Sparrows is one that would fit a Great Tit, with that all important 28mm entrance hole.

You could use two more identical boxes, or simply go for a Sparrow colony nest box as its less hassle to fix high up on the house eaves.

Jackdaw

You can't buy bird boxes for use with only a Jackdaw, instead you need a bird box that is intended for say a Little Owl or Kestrel, and hope a Jackdaw nests.

Jackdaws are known to take to a nest box belonging to an Owl or a bird box used for smaller birds, though the standard entrance hole should be 120mm square hole.

You're unlikely to have a Jackdaw nest in a busy urban garden as it would rather take to one deep in the woodlands, or at least a wooded garden nearby.

Kestrel

Incredibly, this bird of prey will take to a nesting box setup for it in a wooded area, though only within woodlands or an area with lots of trees.

This large square or rectangular open front box would only be located up a tree.

To distinguish a Kestrel box from say a similar Owl or Jackdaw box, the Kestrel bird box has a perch that is fixed to the front of the box, protruding out to the side.

Kestrels will use the perch to lookout for there next meal, well going back into the box with ease thanks to the large opening.

Marsh Tit

Of all the Tit family, the Marsh Tit is the smallest of the lot, in fact its one of the smallest garden birds in the UK - by up to 2 or 3 centimetres to be more accurate.

The Marsh Tit bird box would be the one occupied by any of the Tits, though we might say even the 25mm entrance is still quite large.

If possible the Marsh Tit might be safer in a box that has an entrance hole that is smaller; say 22 to 23mm with no perch.

Treat the bird box as one setup for a Blue Tit, only the entrance hole needs to be smaller.

Nuthatch

Nuthatches will take to a nest box but rather one that is setup on a tree in a dense wooded location.

Fairly large bird so one that needs a larger bird box with a corresponding entrance hole.

It should be at least a 32mm radius hole and be rounded. Saying that, its known Nuthatches will take to bird boxes intended for use by Tits.

So make it a multi-use bird box to attract a Nuthatch to nest, but its also possible any bird species would nest as the entrance hole allows for most to fit.

Popular bird boxes for a Nuthatch are those unique woodcrete boxes, only because when setup on a tree, the weathering effect blends in with the tree overtime.

Pied Flycatchers

Again, what's good for a Tit is good for a Pied Flycatcher, with a 28mm entrance that could be occupied by anything other than a Flycatcher.

The Pied Flycatcher is also likely to take over a bird box belonging another, so if you have Tits or a mixture of nesting birds in your garden, this one might take over it.

So that's why you should setup a box for a Pied, with an all purpose nesting box making do with a larger entrance hole.

Once they start building there nest using materials for the interior, they will finish it quickly.

Pied Wagtail

Pied Wagtail nest boxes are designed far differently to most we've mention, this is due to the rectangular entrance needing to be facing down, with a overhang protecting it.

There are bird boxes for use with a Pied Wagtail available you just need to seek out specialist builders.

If setting up in the garden the box will need to be located into ivy or full bloom creepers.

This only relates to garden with trees or near a wooded area, rather than those houses further into the suburbs or busy areas.

Starling

We think you'd have to agree we're all not short of a seeing Starlings out and about as we go about our daily lives.

With all these Starlings you would be doing a great service to provide a suitable nesting box for them.

And well any nesting box would do that used for Tits, the difficulty comes in entrance hole size as the Starling requires one with a large 45mm entrance.

Availability of Starling wooden nest boxes are not short, with a purpose made box or a multi-use box with the option to fix a hole with the recommended hole size for Starlings.

Spotted Flycatcher

Its quite possible a Spotted Flycatcher would be happy to take to a bird box with a small rounded entrance hole, or a box designed for a Wren.

Its likely the bird box designed for Spotted Flycatcher in mind would have a rectangular entrance hole that is at least 60mm high and a width of 120mm or so.

Height from the floor to the entrance should be kept shallow so the Flycatcher can perched on the edge to feed the young.

Locating the box is the hard part as the eave of a single-story building is needed, but so is locating it deep in vegetation, but still with a clear outlook.

Stock Doves

Stock Doves take to large wooden bird boxes with equally a large square entrance hole.

What is wonderful about supplying a hand built box for a Dove is it could be one made for either a Barn or Tawny Owl.

Well bare in mind both owls require a box that is designed very differently, but the Dove won't mind so much as to take up a box that is for use by a resident owl.

Location is very similar with an isolated, quiet outbuilding or a mature tree to be just as significant as to where you site a bird box for use by owls.

Though it would need a 120mm square entrance hole at least for the Dove to fit.

Barn Owl

Probably the largest type of hand built bird box that could be made for a wild bird. And that's only because the Barn Owl is a fairly large bird itself.

Size does not extend to cost as these boxes are often made with sheet material such as plywood, so that keeps the cost down.

Complicated design that has a large 120mm square entrance hole with a platform, well below inside the box is where the young stay.

If you require a Barn Owl nest box, make it one with panel to access the interior for cleaning out when not in use.

Tawny Owl

Bird boxes made for Tawny Owls are not as grand or impressive as those ones made for the Barn Owl.

All that is required is a long cube shaped box with an entrance hole that has the same dimensions used for the rest of the box.

Lower down the box would normally have a hatch to open up to access the interior. Its a long box that reaches further than arms length, so you need an access point for cleaning.

Unlike the Barn Owl box setup on inside an outbuilding, the Tawny Owl likes its box sited under a hanging, tough thick branch of a tree.

Tree Sparrow

Same as House Sparrows, the Tree Sparrow requires as bird box that is identical to one that is used for our urban visitors.

Only this box would be setup on a tree in the garden or deeper into the woodlands.

Quite a complex build with up 3 to 4 separate compartments, each one with an entrance hole measuring 28mm - plus a way to access the interior for each section.

Colony nesters so you're unlikely to get a Tree Sparrow to nest in a single box, though it is possible.

Wrap a bird box around a tree trunk with a lower branch to provide extras support.

Big box with some weight to it, so to fix a bird box to a tree you'll need to use suitable metal wiring or the coated plastic type, which protects the tree.

Woodpecker

With an entrance hole that measures 45mm, the Woodpecker will take to a bird box if its only setup in a tree, in the woods only.

It also needs a clear line of sight with a flight path that is clear from branches and nearby trees - the Great Spotted Woodpecker is bit of a fuss bucket.

Saying that it can be quite naughty to, as it hews other boxes in the woodlands to extract eggs or take the young.

Design of a Woodpecker bird box as the rounded hole of 45mm or smaller, with a deep box, with some length between the hole to the base of the box interior.

Birds NOT using standard boxes

Now that we've outlined entrance hole sizes for British birds that use nesting boxes only, there are wild birds who will nest in boxes, but not designed as you'll expect.

Instead these boxes are not boxes at all but rather nests that imitate what would be built by Swifts, Swallows and House Martin in the wild.

So away with the usual square or rectangular box shape and no more standard entrance holes.

Those wild birds whom are willing to nest in artificial nesting boxes take to ones not made in wood, but rather common house build material such as ceramic or fibre-glass.

House Martins

Martins don't use entrance holes in the traditional sense, but more a half circle that is cut into half shell with ceramic boxes fixed to the house eave.

The House Martin cup nester is made from solid material that is not quite wood, with a half-circle entrance hole that is suited to the design of the House Martin nesting box.

However, wood is used to support the back and top sides, creating an enclosed space but also acts as the piece to fix under the eaves.

Single boxes can be used but there's an option to double up with two boxes, as House Martins do like to nest nearby.

Swallow

Swallow handmade nest boxes replicate what they will build in the wild as a kind of half dish, half bowl shape.

When Swallows take to nest boxes made by people, they are not made from wood but rather strong, moulded materials like ceramic or fibre-glass.

It has a wooden back that is used to fix to the house eaves.

If you think this sounds familiar to boxes required by House Martins, you're not far off as its only the entrance that is different.

And its this entrance hole that is not a hole as such, but more a gap allowing access to the bowl from all angles, as it fits tightly to a board above with a 2cm or 3cm entrance.

Swifts

If you get a Swift come down to nest in your bird box, firstly consider yourself one of the lucky ones as its tough to get them to nest, but they will given the chance.

This purpose built bird box for use by a Swift is actually a large box to match that of a large Swift that nests inside.

The entrance hole is larger than most at 28mm by 65mm actually, though give or take a few millimetres has no baring if its nest or not.

This entrance then leads into a large rectangular wooden box with lots of space inside.

Designed to be located high up under the eaves, the box has a sort of angle to it as the entrance hole faces down, so this angle prevents the birds or young from falling out.