The glamorous eye of the brown cuckoo-dove

We’ve had a visit from some old friends this week: a gorgeous pair of brown cuckoo-doves. who each took a constitutional around our patio before reconvening for an exhaustive mutual preening session above the chicken run.  They’re rainforest birds, but don’t mind wandering away from damp gullies in search of tucker – fruit, mostly, along with seeds and the occasional flower blossom.  You’ll often find them in disturbed areas and roadsides, feeding off weeds like lantana and wild tobacco, so what with the great swathes being carved, legally and illegally, through East Coast bushland, they’re doing better than many other forest loving critters these days.

And they are expanding their range as well.  Back in the day, Sydney was the southernmost point you’d reliably find a cuckoo-dove.  No longer.  Just a continuation, I guess, of the species’ earlier journeys from the north, where several close relatives still live. In fact, the amboyna cuckoo-dove of Indonesia  and the Sultan’s cuckoo-dove of Sulawesi were considered part of the same species only a couple of years ago when I last wrote about these portly visitors.

Brown cuckoo-dove quenching its thirst in our bird bath

I’m not sure what attracted them to our place, now we’ve executed the humungous broad leafed privet that used to lure them here.  The fruit-bearing natives we’ve planted to replace this nasty weed – lillypillies, blueberry ash, koda, bolwarra, native gardenia, small leafed tamarind, brush muttonwood – are all too teeny to offer snacks of any significance.  I spotted the cuckoo-doves innocently drinking from the bird bath but I suspect they may also be implicated in the overnight disappearance of the fruit from our mulberry tree.  Though since I chose to plant the mulberry right next to our washing line, maybe that’s a good thing.

For me, cuckoo doves are all about those beautiful blue eyes, though their exceedingly long tails are also a feature, helping them with fruit nibbling acrobatics, and at one time  earning them the name pheasant-tailed pigeon.  But as far as science is concerned, they’re mainly interesting for their body lice.

A female brown cuckoo-dove being groomed by its mate

Normally, it seems, parasites co-evolve with their hosts.  A family of lice tend to be found only on one family of birds (and in fact, each species of lice normally exclusively hang out with one species of bird).  But the Ischnocera – the family of louse that this pair are trying to remove from each other, in a rather romantic manner – can be found on all manner of birds – not just pigeons and doves, but also pheasants, quails, partridges and indeed megapodes.  Though not apparently our local megapode, the brush turkeys, or “the bloody bloody brush turkeys” as they are usually referred to in our household.

But if cuckoo-doves brought their own personal payload of body lice with them when they moved south to Australia, they also do a fine job of cleaning up some other pesky insects –  fruit flies.  Along with ripe fruits, cuckoo-doves gobble up loads and loads of larvae.  One researcher went so far as to say that vertebrates like brown cuckoo doves are the “natural enemies of fruit flies” (Drew, 1987, 287), words to bring joy into the heart of a sub-tropical gardener.  But further reading crushes these dreams.  Yes, cuckoo-doves, (along with rats) made a huge dent in the fruit fly population.  But unfortunately, they did so in the course of eating most of the available fruit.

I guess, then, its lucky I’m hooked on the looks of our frugivorous visitors, and I’m not banking on them for pest control.

The blue eyes of the brown cuckoo-dove

Additional references

Drew, A. J. I. (1987) “Reduction in Fruit Fly (Tephritidae : Dacinae) Populations in their Endemic Rainforest Habitat by Frugivorous Vertebrates” Australian Journal of Zoology 35 283-8

Gibbs, David (2001) Pigeons and Doves: a guide to the pigeons and doves of the world, Bloomsbury Books

Gosper, Carl and Gosper, Dennis (2008) “Foods of Pigeons and Doves in Fragmented Landscapes of Subtropical Eastern Australia” Australian Field Ornithology, 25, 76–86

Johnson, Kevin, Weckstein, Jason, Meyer, Mathys (2011) “There and back again: switching between host orders by avian body lice (Ischnocera: Goniodidae)” Biological Journal of the Linnean Society, 2011, 102, 614–625