The birdbaths which decorate gardens up and down suburbia have emerged as an area of conflict for our birds, especially during a summer of drought like the one we have just experienced in Tasmania.
The “battle of the birdbath” has been the focus of a nation-wide survey over the past two years to determine which species are able to dominate these unnatural sources of water, and which species are shut out.
The results of the survey so far have thrown up some surprising results, dramatically separating native and introduced species. It appears in the northern half of the country – from Sydney upwards – it is the natives who rule the roost. It was thought that introduced birds like the aggressive common Indian myna would dominate but in the warmer regions of the country such native species as rainbow lorikeets and noisy miners are holding their own.
In the cooler south of the country, however, the picture is very much as expected. The dominant force at Melbourne water stations are mynas, starlings, blackbirds and sparrows.
I’m happy to report that my own survey of the birdbath has revealed that a native species, the new holland honeyeater, is proving to be a force to be reckoned with. My honeyeaters see off all-comers, even the much larger yellow and little wattlebirds which are known to dominate not just birdbaths but flowering plants in gardens throughout Hobart. Introduced birds like the blackbird, starling and spotted turtle doves also do not stand a chance.
Studying the honeyeaters over the years, I’ve found they adopt a strategy employed by noisy miners a little further afield to muscle other species out of the way.
The especially aggressive noisy miners employ a tactic known as mobbing behaviour in which they swoop down in big numbers, shrieking all the time, to scare of other birds getting in their way.
The noisy miners are such a menace in gardens that one noted birdwatcher once wrote in a book on gardening for birds that he would not buy a property if noisy miners laid claim to the garden!
I’m lucky that the noisy miners in Hobart prefer drier, open areas nearer the coast and so do not venture along the wet and forested Waterworks Valley where I live. The same goes for another aggressive species in the garden, the grey butcherbird.
The best place to see both miners and butcherbirds in action is around the Hobart Aquatic Centre at this time of year where they constantly bully the eastern rosellas feeding on seed provided by the ornamental cypress and silver birch trees.
The survey of birdbaths, led by Deakin University researchers, was designed to explore the nexus between urban life and wildlife and it has already suggested that in a dry continent like ours birdbaths are a vital resource for birds.
The survey is being expanded in scope to investigate how many bird species make use of birdbaths and food provided for them, and what prompts people to offer them a helping hand. To take part go to www.feedingbirds.org.au