Building an owl box

"Corujas" means "owls" in portuguese. Since it's the name of the farm and since owls look great and hunt mice we've always wanted to have one. But we don't want a pet owl. We went to a bird-of-prey exhibition and were told that if you get a tamed owl you'll have to feed it yourself. We wondered how you'd get a wild one and the response was "How do you know you don't have one now?". That made sense. We often see hawks and eagles flying over the farm and sometimes hear owl-like calls at night. Since owls are exclusively night animals we figured there was a good chance one was around already. The matter was settled when I was out for a jog at night in the city (not the farm) and saw a beautiful white owl flying overhead between two fields close to our house.

So the way to get an owl to permanently move in was to just provide it with a place to nest. You can buy pre-made boxes but we looked up plans online and decided on building our own box. The best plans seem to be this PDF based on an original design by Steve Simmons. We didn't follow the plans exactly. Our initial setup was basically a 50cm cube:

We painted all the outside with an Ikea wood protector (any wood preservative should do) and used a dremel to create some footholds and a jigsaw to open up the entrance hole:

We put in a hinged door to make it easy to go in and clean the box once it's in place and folded a metal sheet to create a roof, since that's the part most exposed to the rain.

We picked the spot to put it up.  Here's the box installed on the top of an old stone pillar that was originally supporting a traditional wine vineyard:

We went a little overboard in making sure the box was properly attached. We attached it with three shelf brackets as well as to the metal pole already attached to the stone pillar with some metal strips.

Hopefully we'll be able to attract an owl to nest in the box. We were too late this year as the nesting period is late winter. Hopefully next year we'll have some luck. And owl should help with reducing mice populations. We should consider building a bat house to help with mosquitoes. We're sure we have bats as we often see them flying around at dusk.


This is a blog for Corujas, a small farm, and the family who cares for it. For us, Corujas has a bit of everything. It is a place with family histories that merge into the present. The place had been in benign neglect for decades and nature took over, with a great diversity of native things popping everywhere. The house is a shelter from the sun and the cold and the patches of garden are a sample of tamed nature with some exotic species. The whole ground is an experimental field for the technologies that will hopefully ease our life and for the gadgets that keep us geek enough. It is the place we hope our friends will enjoy as their own.

We have cared for Corujas for 12 years, and it has turned from a secret place kept by big mounds of blackberries to a liveable place that will feed us and keep us warm. It has been 12 years worth of weekends, holidays and spare time to buy materials, plan a vegetable or a herb garden, collect cuttings to obtain our favourite species or wait for seeds from heirloom tomatoes to sprout.

All this time, intuitively, we have avoided cleaning too much. This leaves us with months of wild flowers on display, a different one every week in spring, as well as amazing mushrooms and dried herbs and grasses in autumn. We have also resisted the local advice to put down the various kinds of oaks growing everywhere, from pathways to walls. Every year some of them are felled and provide wood, making room for everything else to grow.

Most of the time there was no time to record or document systematically. But thanks to the piles of photos, untidy papers and the bad habit of keeping everything, we hope the history of the past 12 years will be written piecemeal.