Natural tree hollows are an invaluable resource for many of Australia's native birds and mammals. They provide shelter from the elements, protection from predators and a place to rear young. However, increasing pressure on the landscape from human activity has resulted in a rapid decline in the number of large hollow-bearing trees.
Nest boxes can help to alleviate this competition and promote breeding in many native species. They can be particularly valuable in areas where feeding resources remain, but nesting sites have been lost, eg. in suburban parks and gardens. Providing shelter for these animals, both by planting and/or preserving Eucalypts and installing nest boxes, not only aids their survival but may reduce conflict with the human population by reducing the number of animals using buildings and roofs as their homes.
Each species varies in size, shape or breeding requirements, and has different, although frequently overlapping, needs which a nestbox can supply. These include different depths, lengths or shapes of hollow, size and placement of entrance, height above ground, and protection from predators. There are different designs of nestbox, and different placement requirements, for most kinds of hollow-using bird or mammal you are likely to find in Australia's suburban parks and gardens.
Nestboxes, more than anything else, provide protection from the weather and from disturbance. They need to be well insulated from wide temperature fluctuations, rain-proof and facing away from prevailing winds and direct midday summer sunlight. They need drainage holes to prevent moisture build-up, and must be attached firmly so that they will not vibrate nor be easily detached by a predator.
Just by keeping regular notes of what birds are present, in what numbers and what they are doing, you become environmentally aware. The notes for any one day may not seem particularly significant, but over the months and years they build a valuable record of population seasonal changes, responses to droughts or bushfires elsewhere, and long-term declines or increases that reflect major environmental change.
By contributing your information to our Wildlife Watch community environmental surveys you will be helping to sound the alarm on damaging trends so that we can do something to halt or reverse them.
To find out more about creating a suitable habitat for wildlife, go to our Native Havens web page.