The cuckoos have stopped calling, their cunning work done for summer.
In the first week of the new year, the fan-tailed cuckoo seemed to be the only cuckoo calling at the Queen’s Domain in Hobart where just before Christmas the calls of not only fantails, but pallid and shining bronze-cuckoos had bounced off the gums and casuarinas.
The adults might have fallen silent but the dry woodlands were filled with noisy cuckoo young, making life difficult for overworked surrogate parents.
As is well known, cuckoos do not raise their own offspring but deposit a single egg in the nest of an unsuspecting host.
This, of course, saves the cuckoos the effort of raising their own young although it has been found that at least one of Tasmania’s four cuckoo species, the pallid cuckoo, returns on occasion to collect the youngsters and prepare them for the migration back to the mainland at the end of summer.
There is no more troubling sight at this time of year than seeing frantic “parents” of chicks often considerably bigger than themselves trying to keep up with the demands of hungry cuckoo youngsters.
In the case of the pallid cuckoo, the biggest of the family seen in Tasmania, I have seen black-headed honeyeaters half the size of a 30 centimetre chick struggling to keep up with its demands for food, the cuckoo pecking at the honeyeaters in anger and frustration.
The orange-yellow, wide gapes of young birds act as a signal for nestlings of all species to be fed, the young cuckoos exploiting these urges with bigger and brighter beaks.
It’s not unusual for other species other than the hosts to join in the feeding frenzy, on one occasion a scarlet robin joining black-headed honeyeaters in feeding a cuckoo chick.
Apart from cuckoo antics, mid-summer can be a joyous occasion with the forests, woods and paddocks alive with young birds.
The soundscape of the environment also changes, territorial songs of male birds replaced by the begging calls of the young. These can be loud, insistent and repetitive.
Young birds on the wing and shedding their nestling feathers can also present a challenge to identification. Fledglings about to leave the nest lose their downy feathers and moult into a juvenile plumage that lasts for some months. With some species, this can look very different from the adult plumage, while for others the differences are more subtle. Juvenile livery is usually more mottled or streaked, offering better camouflage.
The size, shape and bills of these juveniles is similar to the adults and are good clues to identity, although the tail and wings can be shorter in recently fledged young. Generally, these birds are able to fly but are still dependent on their parents, and in the process are the ones filling the woods with their begging calls.