Friday, August 29, 2008

How I Do Nest Boxes

G’day All,
Especially Mick and Mosura. Strewth, are you sure you want my philosophy on nest boxes? Alright, here goes.


I make them out of whatever scrap material I can find around the place. Old tongue and grooved flooring is good, as there are no gaps between the boards for cold draughts or moisture to get in. The nominal dimensions for a rosella sized parrot box are, about 250mm x 250mm in cross section, about 400mm high and a 70 to 80mm diameter entrance hole.

I’m not too fussed about the size. When you see some of the nesting sites of these birds in the wild, the dimensions suggested above would seem like a mansion to them. I have built some larger versions in the past and while the birds did occupy them, I nearly killed myself lifting them into position on top of a ladder.

I don’t bother with hinged lids, I just screw on a nice watertight flat roof. I only need to clean out inside the box once every year or two, so there’s not much work involved in undoing a few screws. The roof has a bit of overhang to help keep the weather away from the entrance hole.


Sometimes I put a ‘ladder’ on the inside front wall, just under the entrance hole. It just consists of a stick or two attached to the wall so that the young birds can climb up to the hole easily when they fledge. More often though, I don’t bother with this either, as you discover they will nest at the bottom of hollows several metres deep and they can still climb out ok. Also, one time when I did the clean out, I discovered all the ‘ladders’ had been chewed off.


Next, I attach a short piece of branch flat on the outside front wall under the hole. At one time I read a theory that suggested a perch protruding straight out from the nest box was too inviting to all sorts of other birds, particularly Indian Mynahs. We do have mynahs here and I’ve never seen one at any of the nest boxes.


The final bit of the construction stage is to add some means of attaching the box to a tree. My early attempts involved screwing the boxes rigidly to the trunk of the tree. These boxes soon began to disintegrate. I think that as the tree grows, sways and twists in the wind, the forces on the attached box caused it to slowly break apart. Now I put an eye bolt in the top of the box to hang it from a hook and an eye bolt each side so that I can attach a light chain for wrapping around the trunk – more detail later.


If the box I’ve built is made from softwood, I give it a coat of paint to help protect it from the weather. Hardwood boxes I tend to leave unpainted and they look great as they weather naturally. After tossing in a small handfull of sawdust from the woodheap, or leaf litter from under a tree, the box is ready to put in place.


I’ve put boxes in very concealed spots and very open spots – they are both utilised. I’ve put them up high and down low and both those localities are utilised. Like in nature, they will nest almost anywhere. A pair of easterns nest each year on the golf course about 5 metres from a green, in a very skinny hollow formed between the trunks of a double trunked tree, no more than knee high from the ground.


My first priority for selecting a spot is to pick somewhere that I will easily be able to monitor it. No problems around the garden, almost anywhere is accessible. On the golf course, I’ve picked spots that I pass nearby regularly as I do the watering or mowing. The tree has to be reasonably substantial of course and it’s best if the trunk is vertical. Usually I try to face the box to the north or north-east, as most of our worst weather comes from the west and the south.

Here’s the easy bit. Most of the boxes I put up now would be no higher than 3 metres from the ground. I select a spot, put the ladder up, screw in a galvanised coach screw at a slight angle above horizontal and hang the box on it. I attach a small tension spring to one end of the chain and then using one of those handy snap-on clips, attach that end to one of the eye-bolts on the side of the box. I wrap the chain around the trunk, apply a bit of tension via the spring and note where I need to cut the chain to reach the other eye-bolt. Using another snap-on clip, I attach the chain to the second eye-bolt. Job’s done!

Suspending and ‘chaining’ the box makes it very easy for getting down later for cleaning etc. The chain and spring system allows for some movement from the tree but holds the box firm enough without ringbarking the tree.



Finally, lately I’ve been salvaging any small and suitable hollow logs when I’ve been collecting our firewood. I always feel a little guilty getting firewood. It is a renewable source of course, but even lying on the forest floor it is great habitat for lots of fauna. I’ve covered a few holes with timber cut to shape, and I’m hoping that in the right place, these might entice some Pardalotes or Bats, Feather Gliders …? Anyway, it makes me feel a little less guilty about getting firewood.



I hope this has answered some questions Mick and Mosura. Why not have a go?

Regards,
Gouldiae

4 comments:

  1. Can only read in admiration at your dedication to the birds. What are your thoughts about cutting into 'weed' trees to create habitat hollows?

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  2. Thanks very much for taking the time to post that information. Even though I downloaded a large pdf file on nest boxes I still found loads of useful ideas in your method. I like the idea of just screwing down the lid. In Scotland, if the lids were not on tight the crows would actually lift them open. I was also going to put a perch on mine but will now do as you suggest.

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  3. Thanks Gouldiae for posting this. It is very clear and certainly very interesting. Now I wonder where I could find to attach one?? One further request - if birds occupy your nesting boxes can we have further photos?

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  4. G'day T, M and M,
    Thanks for the interest.
    I don't know Tony, it'd probably work. How would you cut a hollow into it? Interesting!
    Good luck with it Mosura.
    Yes Mick, I intend to get a few shots. Usually I leave them alone while they're selecting their box. Once they 'move in' they tend to be much more approachable. Uhm, after putting up 2 boxes near the house, I lightly pruned a couple of branches from nearby trees that were blocking my line of sight and causing the camera focus ring to jump sideways!
    Regards all,
    Gouldiae

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