Blue eyes and biteys

Brown cuckoo dove eye

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.

Cuckoo dove looking back from water crop

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.

Cuckoo dove long tail amend

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.

Cuckoo pair grooming 2 amended cropped

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.

Gorgeous eye closeup for amend

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

Bananas: my part in their downfall

Yes!  We have bananas!

Two and a half years after planting my first “cool banana”, it looks like we have a crop on the way. With luck and a tail wind, we might get a few home grown smoothies before the upcoming banana apocalypse.

In fact, our fruitful plant isn’t the first one I acquired – a tiny carefully selected, soil-free, tissue-cultured plantlet sent by mail-order from Queensland.  It’s one of a job-lot grubbed up and bundled into the back of the car when my sister decided to give her backyard jungle in Newcastle a makeover.  This particular tree seems to have the right kind of humid micro-environment, protected from the wind by the tamarillo tree and surrounded in a companionable way by monstera deliciosa, ginger and tumeric plants.   It gets some winter sunlight, and some gifts of love from the chickens in the form of dung-encrusted sugar cane mulch.

For all my attempts to recreate a tropical ambience, I haven’t gone quite as far as using my bananas as a living shower screen.  This idea seems strangely popular in permaculture circles, due I think, to the banana’s love of phosphorous, frequent watering and good drainage.  I’m no stranger to nakedness in the outdoors thanks to many happy  hours in childhood spent camping on nude beaches (in retrospect I witnessed surprisingly few cooking-related injuries).   But I’m not really sure how practical backyard ablutions are in suburbia, even in the sub-tropics.  There seems to some wishful thinking about unfettered encounters between man and nature (or, more specifically if disturbingly, woman and banana) going on here.

While I’m on the theme of soft-focus fantasies of interspecies coexistence, I have to confess to one of mine – that our backyard is a little island of biodiversity.   This is the kind of thing plant-hoarders tell themselves as they croon and mumble over on-line nursery catalogues.  But thanks to my impatience to start growing the world’s largest herb, three long years ago, I didn’t order any of the more intriguing possibilitiesBluggoe or Blue Java or Goldfinger – but just common or garden dwarf Cavendish – the world’s most widely grown variety.

It wasn’t always so.  In the early twentieth century, the dominant variety was the Gros Michel – by all accounts sweeter and more flavoursome than the Cavendish (if less productive).  Your grandparents were right – everything did taste better in the good old days.

But in the middle part of the twentieth century Panama Disease, a fusarium fungus, wiped out most of the commercial plantations of Gros Michel in Central and South America.  Panama disease is a doozy – transmissible through infected soil, water or equipment and impossible to eliminate or treat.  Once the ground in an area is infected it stays that way for decades.  Over the years, the big banana producers kept moving from country to country to keep the banana plantations going but eventually, thanks in part to multinationals and agricultural monocultures, the disease had spanned the globe.

So in the 1950s, the world switched over to a less tasty variety of banana – Cavendish – more resistant to Panama disease, or at least its early twentieth century incarnation, Tropical Race 1.

It’s not just Panama Disease.  There’s Black Sigatoka, as well, and Bunchy Top, the latter hard to take seriously since it sounds more like a Loony Tunes character than than a devastating agricultural blight.  Bananas are particularly susceptible to disease because we’ve bred them to be sterile: seedless mutants that replicate through their genetically identical “daughters” and “granddaughters”.  Commercial bananas have three sets of chromosones – they’re triploids, just like our old friends, the herpes-ridden Pacific Oysters of Broken Bay.

Genetic mutations can happen without sex but it’s a painfully slow process. And retrofitting disease-resistance without recourse to selective breeding is equally tricky, unless you want to go GMO. An article in Conservation Magazine described an attempt to do it the old fashioned way:

Every day for a year, workers laboriously hand-pollinated thirty thousand banana plants with pollen from wild fertile Asian bananas. The resulting fruit, some 440 tons, had to be peeled and sieved in search of any seeds. “I’ll let you guess how many seeds they collected,” says Emile [Frison, head of International Plant Genetic Resources Institute in Rome]. “About fifteen. And of those, only four or five germinated.

Those of us who enjoy a banana with breakfast should really be fearful of an attack on the clones.

And sure enough, Tropical Race 4 Panama disease, unstoppable killer of Cavendishes and pretty much every single variety of bananas and plantains, appeared in Asia and the Northern Territory in Australia for the first time in the 1990s.  And in March this year, it turned up  in Tully in far north Queensland, the place that around half Australia’s bananas call home.

The fact that TR4 attacks so many varieties of banana makes it a threat not just to first world breakfasts but to hungry people across the globe, for whom plantains, in particular, are often a staple.  After a couple of decades in a holding pattern, TR4 has in the last year cropped up for the first time in the Middle East and in Africa, which is worrying – if you have any mental space left for additional worry about the general direction the world is going.

Given the kick-arse nature of Tropical Race 4, perhaps my unimaginative choice of varieties and ad-hoc acquisition of plants isn’t such a big deal.  Newcastle may one day be a commercial banana growing area – in fact, this would seem an entirely appropriate fate for the world’s largest coal export port.  In the meantime, moving these suckers around isn’t a criminal offense like it would be in Queensland, where your backyard banana should spring from a test-tube and come with a permit from the Department of Primary Industries.

I may be the handmaiden of monopoly capitalism, monocultural agriculture and globetrotting disease, but despite all that I think I’ll chill and allow myself to enjoy however many bland tasting Cavendish bananas escape the indiscriminate attentions of the possums, the fruit bats and the grasshoppers.