EVERY year there’s the bird that got away, the species that eluded me in the summer months. Last year it was the satin flycatcher, this year another migrant, the shining bronze-cuckoo.
Cuckoo songs are loud and far-carrying, as much a part of summer as the whirr of the garden strimmer and lawn-mower. We all hear them in the suburbs without knowing of the birds making these strange sounds.
Two of the four cuckoo species visiting Tasmaniain summer, the fan-tailed and pallid cuckoos, are easy to spot because of their relatively large size but the two species of bronze-cuckoos each year demand that I go on a marathon search for them, especially the more common shining bronze cuckoo (Chrysococcyx lucidus). It is also the sound of summer but rarely shows its face.
The nature of cuckoos’ cunning business is to stay concealed and not reveal their true intentions. We all know how cuckoos use surrogate parents to raise their young, laying their own eggs in the nests of their hosts when they are not looking. The host species clearly recognise shining bronze-cuckoos and the threat they pose, and are seen to chase and scald the parasites whenever they come across them, but the cuckoos still manage to beat their defences with such success that each year their calls remain one of the most common sounds of summer, even if they are rarely seen by the human population.
The shining bronze-cuckoos has a monotonous, single note call that is on a descending scale. After a time it can become very irritating, far worst than the song a species of pigeon, the brush bronze-wing, that sounds to me like a trunk reversing when I hear it.
Out of the four species of cuckoo visiting Tasmania each summer, the shining and other closely related family member, the Horsfield’s bronze-cuckoo, are the most beautiful. As their name suggests, they are a stunning, shimmering bronze-green in colour, the shining bronze-cuckoo having faint green and white bars across its chest.
They are much smaller than the bigger cuckoos, the pallid and fan-tailed, and like to conceal themselves in thick foliage, from where they can watch the movements of birds courting, mating and then building nests.
As soon as eggs are laid and the host parents are not watching, the female cuckoo promptly slips into the nest to lay her own single egg. The cuckoo tends to grow faster than the other chicks, claims all the food being brought to the nest and finally evicts the other young.
With all this cuckoo activity, you’d expect the bronze-cuckoos to be easily noticed but they manage to evade detection, and are only noticed when they are on the wing, their general long-winged profile like that of a raptor.
In previous years when I have managed to get brief glimpses of shining bronze-cuckoos, I’ve noticed that they stand low on bough and branch, either exploiting light and shad to hide in the shadows or relying on their bronze-green plumage to merge with the colour of eucalypt leaves, which can often be of a similar hue in sunlight.
From the old gums trees that tower over my neighbourhood, the bronze-cuckoo song rang out, day in, day out, sometimes even at night during the summer months.
I’d hear it at dawn, and still be hearing it at dusk. I kept binoculars at the bedside, leaping out of bed with the first rays of the morning sun, scanning the trees in my pyjamas. The bronze-cuckoo tormented me, as if knowing I would hear its call and then search in vain to find it. I felt a little like the birds it preys on – feeling its menace but never seeing it.