DARWIN’S FINCHES: THOSE OF THE TOP END, NOT THE GALAPAGOS
Australian birds are bright and beautiful, and are valued by the public as shown with a species of honeyeater recently appearing on the new $5 note. Birds of northern Australia are no exception, with the tropical environment harbouring many colourful species of various sizes. Australia, as a large isolated continent, has an array of colourful and diverse birds, including finches. Finches are commonly encountered throughout Australia, but the tropical north is a special place for this group of birds. There are 21 species of finch in Australia, all belonging to the Estrildidae family, and all but four are endemic to Australia. These birds differ to what the rest of the world call ‘true finches’, which are small passerine birds belonging to the family Fringillidae. Species from this family are represented in Australia by introduced species only.
Finches are popular with aviculturists throughout the world for their bright and beautiful colours and are often bred to produce new varieties. Not only are finches popular with bird breeders, they are also most sought-after on a birdwatcher’s list, with birders and twitchers travelling to places throughout Australia to see these beauties. The Gouldian Finch is commonly regarded as one of the most spectacular finches in the world, with its striking colours and its variety of head colouration – red, black and yellow forms. This species of grass seed-eating finch is usually high up on the bird list when birdwatching in northern Australia.
If you follow the finch trail, you’ll find yourself visiting all corners of the continent. In the south-west of Australia, the Red-eared Firetail is restricted to areas around the Perth region. The eastern equivalent, the Beautiful Firetail is found in south-eastern Australia and Tasmania in dry forests, heath and scrublands. Driving through Australia’s central region will produce large swarming flocks of Zebra Finch; look for birds near waterholes or bores. This species is another popular bird in aviculture and is more recently referred to as the bird equivalent of the lab rat (the Zebra Finch is often used in experimental and behavioural studies and is the go-to species when bird testing in a lab is needed). The Blue-faced Parrotfinch has a narrow range in northern Queensland and is found in high rainfall and high altitudinal zones of the Atherton Tablelands region. The common and urbanised Double-barred Finch is possibly one of the most delightful species of finch with its ‘mew, mew’ call, it sounds as cute as it looks. In northern Australia you can hit the finch jackpot, with up to 11 species of finch to be found in a variety of habitat types.
The Top End of Australia is home to an assortment of finches because of the habitat types that these birds prefer. Like most finches, the species present in the Top End can be found close to surface water on open grasslands or savannas. Dry woodlands with watercourses are particularly appealing to finches and spending a morning watching a waterhole can produce many seed-eating finches and other dry country birds. As most finches are highly sociable, large flocks of birds can be found throughout most months of the year. These social meetings of finches bring birds together to feed, bathe, rest and preen. Large flocks can be heard flying overhead as birds fly between sites, calling constantly to one another to maintain social connections. While some finches in the Top End breed in tree hollows and in grass and reed beds, the Crimson finch, a striking bright-red bird during the breeding season, nests and shelters in Pandanus plants, a species of plant you might be familiar with because of its thorny exterior.
Spectacular courtship displays depict the interesting social bonds of finches, as male birds parade and dance with grass stems held in their bills in an attempt to attract female birds. Breeding events in finch species depend on the availability of grass seed-heads, which in turn depends on rainfall and temperature with the main breeding season of finches in the Top End occurring at the end of the wet season. However, with the dry savanna environment there is fire close by, and fire will dictate the availability of food in the ecosystem. Fire drives food phenology and the movement of finches across the landscape as birds seek resources crucial for their survival.
These small birds of many bright colours add vivid bursts to the otherwise green and brown backdrop of savanna woodlands in the Top End.
Amanda Lilleyman is an ornithologist and specialises in migratory shorebird ecology in Darwin. You can find her at her desk writing up her PhD thesis. Follow her via twitter @alilleyman
Photo credit: Brian Thistleton
