Many of our native animals rely on tree hollows to survive but a loss of old trees has made them hard to find. Adding a nest box to your garden can help.
Every species has different requirements for things like height, width and the size of the entrance hole. Check out the chart below, adpated from Faunature, for a guide.
Wildlife species | Orientation | Height (cm) | Depth (cm) | Entrance hole (cm) | Above ground (m) |
Pardalotes Tree martins | - | 10 | 10 | 3 | 1+ |
Grey shrike-thrush | - | 25 | 18 | 9 x 9 | 2+ |
Microbats | Vertical | 30 | 15 | 1.2 – 1.5 | 4+ |
Pygmy possums Yellow-footed antechinus | Vertical | 30 | 15 | 2 | 1.5 – 5 |
Small parrots Tree creepers Owlet nightjars | Either | 50 | 15 | 4.5 6 8 | 4+ |
Medium parrots | Either | 55 | 20 | 7 | 4+ |
Brushtail and ringtail possums | Either | 45 | 25 | 10 | 4+ |
Small ducks | Horizontal | 45 | 35 | 10 – 15 | 2+ |
Kookaburra | Horizontal | 30 | 30 | 12 x 18 | 4+ |
Barn owl | Horizontal | 40 | 40 | 22 x 15 | 6+ |
Cockatoos* | Vertical | 100 | 40 | 18 | 10+ |
* Yellow-tailed black cockatoos prefer a design like Carnaby’s cockatoo.
Boxes for some species may require features such as drainage to avoid drowning, sacrificial chewing posts, and ladders for exit and entry, so be sure to thoroughly investigate the requirements for your target species before installing.
Common species are likely to be the quickest to take up residence in these new homes. Threatened species may take longer, however supporting this rare wildlife is particularly rewarding, and of greatest benefit to the environment.
Find out more about the importance of tree hollows.
Photos courtesy of Martin Stokes and Elisa Sparrow.