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Aparrows perched in window bars

Do window nest boxes work?

Its certainly a challenging prospect encouraging birds to nest in a bird box, but made more difficult when its a window bird box.

In our opinion, window nest boxes are unlikely to work for most people; put this down to lack of options that are only available with a traditional wooden box setup. All that is required for a bird to nest or roost is not possible with window boxes; lack of entrance hole options, location and height are limited.

Wherever you find yourself locating the window nest box, make it so the viewing area on the rear is covered; being open to people moving around in the house won't help at all.

If you're ever going to get a bird to nest in the box it must be setup like a regularly sited bird box, as to not deter them with fancy gimmicks.

And be warned, the use of a window nesting box is a fancy gimmick, and not practical.

If you do succeed in a wild bird nesting in the box then exposing the back to you glaring in would possible scare them away before they nest, let alone roost for the night.

Always keep the back covered that is attached to your window, and only when you're certain you'll not disturb them, take a peak.

Disappointing in the use of window feeders are they're not made to be used as advertised; the idea of bird nesting well you can look at them around the clock, it just doesn't work like that.

Treat it like siting regular bird boxes

Take all advice available to you where to site a regular bird box out in the garden, as the same rules apple.

And believe us, the idea of locating a bird box in the perfect spot well easy, its still difficult to get birds to nest in traditional wooden nest boxes.

With that in mind, you'll absolutely need to stick the box on a window that is only north/east facing, out of direct sunlight and only on the shaded side of the house.

You'll have to take the advice of which way to face a bird box and then fix it to a height that is acceptable to a garden bird you wish to attract.

Positioning a bird box requires facing it in the correct direction, height and whether you need to fix it within scrubs and plantation, and that applies to most wild birds that nest in bird boxes, particularly Blue Tits, Coal Tits, Great Tits and House Sparrows.

If you're setting it up yourself to encourage Robins to nest, forget about it.

Most available window bird boxes are only designed with a small rounded 25mm or so entrance hole, so only few small garden birds would take to a box with this hole size.

Robins, or Wrens for that matter require a big rectangular shaped entrance hole that is located only 1 to 2 metres high, fixed way back in scrubs or plants.

So now you have to consider which way to face it, height of the box, and the bird box entrance hole size, its made for more difficult.

Change house window, not position

If you're not getting birds to nest in your window box it might be that the window you've chosen is not suitable for them.

If after you've taken our advice on board in regard to siting a window bird box as you would a proper bird box, with still no interest, then its time to change window.

And this window must still be north or east facing, or anywhere in between as to avoid the direct sunlight and strong westerly winds - we can't stress that enough.

So whatever side of the house you've selected already, you can only fix the box to the remaining windows on that same side.

If you've tried the living or dining room window if both are suitable locations, then perhaps the smaller, much quieter toilet window would be more successful.

Sure, often bathroom windows are glazed but if that doesn't apply to you, give it a go.

When we do mention changing location, we're only referring to windows, not a different location on the same window, it won't make a difference.

Try the shed

If after many months you're not getting anywhere on the house windows, have you ever thought about isolating the bird box by fixing it to the garden shed window.

Don't worry, the suction cups will still take to the plastic windows of the shed, as oppose to just glass windows.

If fixed to a garden shed we can be assured birds will get less disturbance throughout the day and night, well almost setting up a window box similar to normal bird boxes.

If using a shed window it best be a shed that is not regularly frequented to get out the garden tools or bike, but one that is more disused and rarely visited.

Setup the window bird box on a window with a far reaching eave that hangs over wide; well it both protects the box from rain and sun, as well has praying cats.

This shed must still be out of sunlight and preferably in the shade.

If the shed gets hot during the summer months then this will only pass through into the box, making the conditions unbearable.

What makes a good window nest box

If we have to be honest with you, no window bird box makes a good nest or roosting site, the conditions outside and especially in are not a suitable environment for wildlife.

Wild birds demand seclusion with piece and quiet, with people not knowing this well using a window box - though the more successful window bird feeder should work.

If you only want to bring birds close to the window to get a close up view, then certainly consider a window bird feeder only, you might find it more enjoyable.

And well getting birds to feed from a window bird feeder is challenging, you get more from its then setting up a window bird box as birds need to feed.

One thing that we have noticed on many commercially available bird boxes readily available almost always come with a perch.

This can only prove the manufacturer's don't know what they're doing, as bird boxes should not have a perch of any kind

The use of a perch only serves to give a footing to predatory large birds, squirrels and cats, allowing them to get a foothold before taking the eggs within.

And well the box is often made with wood on the three sides, bottom and roof; the clear plastic window on the rear is not real insulation.

Therefore this might result in the box getting to chilly in the winter, or worse; the box will heat up as the heating is turned on in the house.

Weighty bird box

If the box feels insecure to you, then it will feel unsafe to the interested birds.

If you're ever going to get a bird to nest in the box, don't make it so the box is not tightly fixed to the window with cheap suction cups.

It must be fixed nice and tight with absolutely no movement.

When building a bird box for use on a window, most manufacturers will build it light, and where wood is required, its can only add more weight.

But what happens if you get a male and female nesting, its gets heavier right?

If they succeed in breeding and lay several eggs; this delicate time will need to be undisturbed before the hatchlings are born.

And remember, if you're forced to move the box with the occupants inside, you're breaking the law by moving a bird box with nesting or roosting birds inside.

From the get go, make sure your bird box will stay put for the duration of nesting season.

Strength of suction cups

Limited manufacturers produce commercially available bird boxes, so you can only go with what they offer you.

If made cheap - and many boxes are - the biggest issue facing you is not the box design, but rather the suction cups not fixing to windows.

You could help them stick by licking each one before applying to window, or use a wet cloth if you prefer.

If this simple method doesn't work from the get go, send the box back.

You could be absolutely sure by cleaning both the suction cups and window before use, just to not give the seller or manufacturer anywhere to go by refusing.

If the suction cups are not sticking from the get go, they won't work at all, let alone as the box gets heavier if birds visit the interior, or perch on the outside.


So there you have it, as you can probably tell we're not a fan of window bird boxes for the reason birds should be left to nest or roost on there own, without interference.

Its also our opinion the use of window nest boxes should be made illegal by the government, as everything that is required from a window box goes against what experts say, including those at the Royal Society for the Protection of Birds.

You see, its illegal to move or inspect a bird box that is currently occupied.

So how is it possible to sell a window box where people can remove the rear to peer inside the box, surely this will terrify the birds.

Evan more so, when the male and female are nesting, with little options to just pack up and go, what happens to the young birds if they do?

Well a bird window box may suite some people, in our opinion a window box is unlikely to work. And when it does, removing a back panel or any cover you've fixed on the window to help cover them, will only result in birds leaving.

If you must bring small garden birds to your window, forget about the window box.

Instead, go for a window bird feeder, well they will prove challenging themselves, you'll hopefully get an up close view of the beautiful birds that eat at your window over time.

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