Thursday, November 1, 2012

Build a Simple Bird Box....

Hello All,

Unfortunately the weather still hasn't improved and any thoughts of gardening have been dismissed due to the completely water logged conditions here. The fields to the rear of my garden have been under water many times this year but have been submerged completely for the last two weeks now!! Health wise I have been suffering with my hip and back again so in some ways the boggy conditions have probably been at the right time to allow me the rest and relaxation that I'm not usually very good at!!!

Despite being house bound my mind tends to be on the garden and of course the wildlife that I have now become so accustomed to seeing in the garden. The birds have been absent for some time as they have been going through the Autumn moult and of course the wet ground makes worming so much easier for them! For a second year the hedges are laden with berries so unless we get a real cold snap I expect numbers to be 'reserved' again! Having said this I have noticed a slight increase on the feeders so it pays to keep them topped up with fresh grub so  they know that a ready supply is always available in 'Higgy's' garden!!

Thinking of the birds made me realise that now is the perfect time to be making and cleaning bird boxes. Getting clean boxes in place now gives prospective 'tenants' the opportunity to picking the right box ready for the Spring breeding season. If we do happen to get a harsh winter the boxes also serve as a warm place for birds to roost, it isn't unusual for several birds such as bluetits to sleep in the same box huddled together to reserve heat and get through an icy night or two!

So with the above in mind I've dug out my old bird box plan and thought that I'd share it on here for anyone who is interested in making their own simple bird box....

The first thing to think about is the type of wood that you need to use. I favour rough cut and untreated wood as the roughness will help chicks climb out when they fledge and being untreated there is no chance of any nasty chemicals leaching out and harming the birds who will peck at the box to mark their territory and make themselves at home!....


The picture above shows the the wood required for this simple box. Generally I find 15mm-20mm thick wood about the right thickness as it makes a box that is sturdy but not to heavy. Please see below for my size guide....

  •  Back Panel - 120mm wide x 250mm high
  • Side Panels -  120mm wide x 250mm high at rear cut at an angle to 200mm at the front
  • Front Panel -  120mm wide x 200mm high
  • Floor Panel -  120mm x 120mm
  • Roof Panel -   140mm x 160mm
  • To make the box you will need a hammer, water based wood glue, 50mm long nails, galvanised large head roofing tacks, shed felt or preferably 1mm thick rubber pond liner, galvanised wire or hanging fixings and water based wood preserver in your choice of colour.

Now that you have your wood cut and everything that you need, start by fixing together the sides, back and front but include the base at this stage to ensure you get the box nice a square....

I use 50mm long nails to fix the panels together however I also use a thin bead of water based wood glue on each edge to add extra strength. To minimise risk of contact with birds using the box I only use glue on the outer edge which prevents seepage into the inside of the box.
A good tip for this stage of construction is to put the box together using just two nails on each side but don't hammer them all the way in yet as you may need to remove them and adjust if the box isn't quite square!....

Once that you have all four sides and the base in place and you are happy that the box is square you can hammer home the nails and add a couple more in each side to add extra strength. At this stage wipe of any excess glue and make sure that there is no residue inside the box.


Next take your roof section and lay it on top of some 1mm thick rubber pond liner or similar waterproof material...

Cut the liner so that you have enough to cover the front and side edges of the lid but leave at least 70mm off the back edge....

Fix the liner in place by pulling it tight over the edges and securing using galvanised roofing tacks. At this stage don't fix the liner over the rear edge.... 

Pull the liner towrds the back of the lid so that it's tight and secure with tacks along the top face as shown below. You can now trim off the excess liner from the front and side edges so that it is neat....

Place the lid on top of the box so that there is an small even overhang on the front and sides and fix it to the box by tacking the loose piece of liner to the rear of the box. This will hold it in place and act as a hinge when opening the box. In the picture below you will notice that I have actually used two pieces of Rubber to add extra strength....
Finally tip the box upside down and drill a couple of drainage holes in the bottom to keep it dry!


Hole Sizes....

It is your choice if you choose to drill the hole at this stage or prior to the box construction. There are however a few things to consider before reaching for the drill. To prevent predators such as cats and squirrels reaching in and 'hooking' out chicks the hole must be a minimum of 125mm from the base of the box. Your next consideration is what type of bird you actually want to attract to the box as different species prefer certain hole sizes! To help you decide I have included a list of species to hole size....

  • Blue Tit            -  25mm
  • Marsh Tit         -  25mm
  • Great Tit           - 28mm
  • House Sparrow - 32mm
  • Tree Sparrow   - 28mm 
  • Coal Tit            - 25mm
  • Starling             - 45mm
  • Pied Flycatcher - 28mm
  • Nuthatch          - 32mm
  • Redstart           - 32mm

Once your hole is drilled it's worth just slightly 'roughening' inside the box just below the hole as this will give young birds something to help them grip and get up to the hole.

And that's the construction finished!...

Now just choose your colour! Note that I have left the inside of the hole unpainted as although using water based paint I know that occupying birds will generally peck around the hole so I like to make sure that there is as little opportunity as possible for them to come into contact with it.....
You will also need to consider how you fix your box up but this will depend on what you are actually hanging it on. I don't have space to show different fixings but generally I use the galvanised wire and a couple of screws and then adapt it to whatever surface I'm securing it to. You might also want to consider a hook on each side to hold the lid down and prevent squirrels from opening it up to get at the eggs or chicks. Once again there are several options from home made with wire and a screw, to shop bought hooks & eyes, the choice is yours!!...


Locating Your Bird Box....
For the best results generally facing your box in a North-east direction seems to be the most favourable position, however more importantly you want it sited where it is out of direct sunlight and sheltered from prevailing winds and rain. Also consider how easy the location is for a predator to access the box? Putting the box between 2mtrs & 5mtrs high and away from climbable structures will keep it's occupants safe from harm. Generally boxes potentially used by the same species should be situated a reasonable distance away from each other to avoid territory deputes. Distance between boxes used by different species such as Blue Tit and House Sparrows for example isn't so crucial, so if you are limited for space and want more than one box erect boxes for different species where possible. It is a good idea to avoid situating a box near a feeding station as the constant disruption of other birds feeding is likely to prevent the box from being used.

Well that's about it for now folks! I hope that this has inspired you to consider your feathered visitors this winter and of course provide a place for you to enjoy them coming and going also! Sited in the right location and viewable from inside the house can be a thrill when you realise the box is occupied and all your hard work has paid off!....

Please do send me your comments and questions as I will always answer any correspondence that I receive!

Cheers

Higgy