Nest Boxes

 

A great way to help birds and bats is to erect nest-boxes.

To be used by immediately by nesting birds or bats, nest-boxes really have to be in place by the end of February.  However, it’s never the wrong time of year to make one because:

  • A suitable box, erected at any time may also find use over the winter as a bird-shelter.
  • By weathering in over the winter, the box is more likely to be used next season.
  • You'll have it ready as a Birthday/Christmas present for grandma.
  • Putting up a nest-box in January can be a cold, wet and miserable experience so why not put it up on a nice day in the Summer or Autumn.

You can easily buy a nest-box but beware, there's a lot of rubbish about.  Only trust solid, simple designs and beware fussy, ornate ones, as they're often useless.  Here are some tips:

  • The box needs to be waterproof but must have a drain hole in the bottom to allow any water that blows in to escape.  For the same reason, make sure the base of the box is inside the sides and not fixed to the bottom.  If it is the latter, don’t buy as water will be able to track straight in to the box.
  • The lid must fit tightly or be heavy enough to prevent squirrels and cats from getting in and eating the chicks.
  • Avoid designs that have perches under the entrance hole.  The birds don’t use them but they’re perfect for hungry squirrels to stand on.
  • Beware boxes that have been heavily treated.  The smell will have to go before birds will want to use it.

Making a Nest-box:

First, you need to decide what sort of nestbox you want.  There are two basic types: an enclosed space with a small entrance hole (tits, pied flycatchers) and a tray or ledge with or without sides and roof (blackbirds, pied wagtails, robins).

Having said that, all birds have their own special needs and the basic designs need to be modified accordingly.

 
A simple nest box for birds that nest in hollow trees.  This box could benefit from a rubber hinge to guide water away down the roof but doesn't need a catch (see middle picture).

A block of wood on the inside of the lid makes for better protection against flooding and predators.

 

This is a bat-box.  There are only two differences between this and the bird-box.  Firstly,  the backing board is longer, extends below the box and is roughened  to allow bats to climb up.  Secondly, the entrance to the box is on the bottom and not the front.

 

To construct the nest-box pictured, you need:

  • Wood:
    I use old floor-boards as they are a perfect size to easily build a nest-box.  Also, they are relatively cheap and easy to get hold of (and don’t forget that by using old timber like this you are doing a cool bit of recycling!)  You will need a plank at idealy 6” (150mm) wide, 1” (25mm) thick and 50” (1250mm) long to construct one nest-box.
  • Wood-Glue:
    Ordinary PVA (polyvinyl adhesive wood glue) is fine.  However, recently I have been experimenting with some of the new “tube” glues (e.g. “No More Nails” from Unibond or "Liquid Nails") which allow you to work much faster.  So far, results are promising.
  • Galvanised Nails:
    These hold the box together and wont rust.
  • A piece of metal or rubber:
    This is for making a hinge for the lid.  A good source of rubber is an old bycicle tyre.  Alternatively, you can fix a block of wood to the underside and wedge the lid in place.
  • Silicone Sealant:
    For sealing the joins after you’ve finished and ensuring that the inside stays dry, snug and warm.  Look carefully at the label on the sealant tube to make sure you buy one without fungicide – Aquarium sealant is your best bet as this is guaranteed fungicide free.
  • Drills:
    You’ll need two drill bits, a 10mm  wood drill to add a drainage hole to the base and a 28mm (1 1/8th “) wood drill for the entrance hole.  These days, 1 1/8th “ bits are a little hard to come by, the best you’ll probably find is a 25mm bit – try it, they sometimes work.  Be aware that a hole larger than 28mm will allow starlings and sparrows to access the box.  The size of entrance hole is crucial: 25mm – Blue, Coal & Marsh Tits only, 28mm – Great Tits (& all above), 32mm – Nuthatches (& all above).
  • Miscellaneous:
    You will also need a saw, pencil, measuring tape and ideally a tri-square to ensure that your lines are square.

Nest-box Plan

Fixing a Nest-box:

Fixing a nest-box is mostly common sense. 

  • Although they can be fixed at 6' above ground, I'd recommend fixing above 12' to deter cats and children from investigating!  The position needs to be protected from both prevailing cold winds and hot sun (try to fix the box so it faces somewhere in the arc from north through east to southeast).     
  • Try to ensure that the birds have a fairly clear flight path to and from the nest.  If mounting on a tree, be prepared to trim some foliage.
  • Mount at an angle to help exclude rain.
  • Don't crowd boxes together.

More info:

Contact the RSPB on the web or by post, enclosing a stamped self addressed A4 envelope and request a copy of of their leaflet on Nest-boxes (RSPB, The Lodge, Sandy, Bedfordshire SG19 2DL).  If you want to go crazy and learn to build nest-boxes for everything from Pippets to Peregrines you need a copy of  BTO Guide No.23 - Nestboxes by Chris du Feu published by the British Trust for Ornithology.

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