A helping hand (or box) for our indigenous fauna
Published on 30 January 2024
In September 2023, the Glenelg Shire experienced a significant storm event which caused severe damage to many large, mature trees around the Portland area.
A number of these trees supported natural hollows which are a vital part of the ecosystem, providing shelter and breeding opportunities to a multitude of native fauna.
In response to the damage and loss of these valuable specimens, Council’s Parks and Gardens team began researching an artificial hollow program to assist our indigenous animal population.
By supplementing our urban forests with manufactured hollows, we hope to see an increase in important native fauna numbers, with special consideration for those species listed as threatened or endangered such as the Gang-Gang Cockatoo, and the Blue Winged Parrot.
The trial project consists of 23 professionally designed nesting boxes of varying sizes to encourage small-large parrots, possums, bats, owls and Kookaburras to take up residence.
The boxes are professionally constructed by a Victorian manufacturer with the specific requirements of each type of species. Treatments prevent decay, improving longevity and deter off-target species habitation.
Virtually all of the boxes have been installed – they are on trees in areas with suitable conditions to attract and support native fauna, improve visibility for interested community members, prevent pest species habitation, reduce ongoing costs, and minimise impacts to existing healthy trees.
A list of where the boxes are can be requested by the public.
As part of the program, we are also exploring improvements to our arboricultural maintenance processes.
Currently used pruning techniques have proven insufficient to provide hollows for native wildlife in an urban setting. Many dead trees retained for habitat become structurally unsound over time and are removed due to the increased risk to the public, long before a suitably sized hollow for birds or mammals is formed.
Where practical, we aim to begin encouraging contractors to conduct ecological pruning, removing branches using specialist techniques to create rough textured stubs.
Studies show this method of pruning is cost effective, while dramatically improving the colonisation of fungi and small invertebrates.
These colonies significantly accelerate the hollowing process, allowing for earlier habitation of desirable birds and small mammals.
In addition, artificial hollows may be carved within the stem of existing habitat trees by trained arborists.
Studies show these types of hollows are superior in replicating a naturally forming hollow and the desirable conditions for native fauna.
Carved hollows also have reduced risks and ongoing maintenance costs, however due to the higher upfront costs compared to nesting boxes, these types of hollows should be installed on a case-by-case basis.
Prior to installation, habitat trees should be carefully inspected by a qualified arborist to ensure they are structurally sound, of an appropriate size to support a hollow, in a suitable location, and have sufficient useful life expectancy to maximise the return on investment for the community.
The success of the project will be determined by the uptake of habitation by target species and will be professionally monitored yearly.
Ideally, moving forward we will consult with interested local volunteer groups to conduct ongoing studies and monitoring, with the potential to host TAFE or university classes.
If the trial is seen to be successful and community engagement is high, expanding the program would involve purchase and installation of additional boxes in 2025 in conjunction with an increased social media and website presence to highlight the vibrant and diverse species which call the Glenelg Shire home.
Caption: A wildlife nesting box for a large parrot.