Ian’s Bird of the Week -: Little Bronze-Cuckoo ~ by Ian Montgomery
Newsletter ~ 1/6/13
Bronze-Cuckoos have been poorly represented in the Bird of the Week, so here is the Little Bronze-Cuckoo, the smallest if the four species (if we included the related but dissimilar Black-eared Cuckoo) that occur in Australia. All the Bronze-Cuckoos are unobtrusive and are easily overlooked, but the various species have distinctive advertising calls which reveal their presence if you know what to listen for. Male Little Bronze are easy to distinguish visually as they have startlingly red eye-rings and reddish iris (first photo).
The females (second photo) are more non-descript with cream eye-rings and brown eyes, but are distinguishable from the Shining Bronze and Horsfield’s Bronze by smaller size (14-15cm/5.5-6in length) and shorter – ‘broken’ – bars on the breast and belly.
All the Bronze-Cuckoos seem very partial to caterpillars and the bird in the third photo (the same individual as in the second) has just snared a juicy lunch. Being cuckoos, the Bronze-Cuckoos are nest parasites like their larger cousins and lay their eggs in the nest of other species. The Little Bronze uses the domed nests of Gergyones, particularly the Large-billed Gerygone.
The Little Bronze-Cuckoo has several races and the most distinctive of these, the rufous-tinged race russatus resident in coastal Queensland used to be treated as a separate species, Gould’s Bronze-Cuckoo until the two were lumped by Christidis and Boles in 2008. The bird in the fourth photo, photographed near Townsville, is a female russatus and shows the characteristic rufous wash on the breast and tail. The male in the first photo was photographed in the Northern Territory and is a member of the nominate race minutillus. Another non-rufous race barnardi breeds in northeastern NSW and southeastern Queensland and migrates north in winter, and the female in the second and third photos is probably one of these.
I mentioned the calls as being distinctive. The are all high-pitched but that of the Little Bronze is described as a descending series of 3-6 notes and a high-pitched trill. Horsfield’s has descending whistle and the Shining Bronze has a variety of calls but the most unusual is a series of whistles with a rising inflection that is supposed to sound like someone whistling for their dog.
I’ve recently put a musical app called Pitch Analyser on my iPad, and I thought it would be amusing to use it to analyse the calls of these Bronze-Cuckoos. The descending series of the Little Bronze starts close to G7# and ends on E7 or F7, over three octaves above middle C (C4) and the in the highest octave on a standard piano keyboard. Horsfield’s whistle slurs down over nearly an octave from C8 (the highest note on the piano) to E7 or D7. The Shining Bronze also has descending whistle which starts a little lower than Horsfield’s on A7 but also goes down to E7 or D7, while the dog-calling whistle ascends from F7# or G7 to A7 or A7#. The trill of the Little Bronze is F7 or F7# and remarkably constant: it would have no trouble with the famous F6 of the Queen of the Night in the Magic Flute, a whole octave lower. Just thought you’d like to know :-).
Ian Montgomery, Birdway Pty Ltd,
454 Forestry Road, Bluewater, Qld 4818
Tel 0411 602 737 firstname.lastname@example.org
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I love that neat eye-ring of the male. Thanks again, Ian, for telling more about your birds down there in Australia. Check out all of Ian’s Cuckoo Family photos. At present time he has 21 species in his Cuckoo family. The Cuculidae – Cuckoos Family has 149 species as of the 3.2 Version of the IOC.
“It is found in Australia, Cambodia, Indonesia, Malaysia, Papua New Guinea, Singapore,Thailand, and Vietnam. Its natural habitat is subtropical or tropical moist lowland forests. This is the world’s smallest cuckoo, at 17 grams and 15 cm (6 in).
The subspecies rufomerus is sometimes given specific status as the Green-cheeked Bronze Cuckoo, Chrysococcyx rufomerus.” (Wikipedia)
Also according to Wikipedia there are 12 species in the Chrysococcyx genus and IOC shows 13 (shown below)
- Asian Emerald Cuckoo (Chrysococcyx maculatus) by Nikhil Devasar
- Violet Cuckoo (Chrysococcyx xanthorhynchus) by Peter Ericsson juvenile
- Diederik Cuckoo (Chrysococcyx caprius) ©WikiC
- Klaas’s Cuckoo (Chrysococcyx klaas) ©WikiC
- Yellow-throated Cuckoo (Chrysococcyx flavigularis) IBC
- African Emerald Cuckoo (Chrysococcyx cupreus) ©WikiC
- Long-billed Cuckoo (Chrysococcyx megarhynchus) IBC
- Horsfield’s Bronze Cuckoo (Chrysococcyx basalis) by Ian
- Black-eared Cuckoo (Chrysococcyx osculans) by Tom Tarrant
- Rufous-throated Bronze Cuckoo (Chrysococcyx ruficollis) IBC
- Shining Bronze Cuckoo (Chrysococcyx lucidus) by Ian
- White-eared Bronze Cuckoo (Chrysococcyx meyerii) IBC
- Little Bronze Cuckoo (Chrysococcyx minutillus) by Ian’s Birdway