The secret lives of big bold bug-eating birds

In my fantasy life, my garden is filled with the delicate calls of rare and tiny birds that feed exclusively on cabbage white butterflies, flies and mosquito larvae, and pause in their labours only occasionally (at times of the day with particularly flattering light) to perch photogenically directly opposite my back deck.

My real backyard, however, like the rest of Australian suburbia, is awash with great big, loud, gallus beasties: cockatoos, kookaburras, magpies and of course the damned brush turkeys.  Seems like there’s more of them here in Sydney than ever before.

They may be common as muck, these big bold birds, but they’re not to be sneered at.  They have their own mysteries.  How do breeding magpies meet and pair off?  Why are kookaburras so faithful to their mates? How do cockatoos select whose timber house they’re going to rip to shreds?

To be fair, if the bird-life in suburbia is fairly predictable, bird watchers are pretty bog-standard as well.  I love this comment, in an article marvelling at the speed with which bird atlases are compiled, while more unglamorous animals – favoured by God, perhaps, but not necessarily by citizen scientists – live and die in obscurity.

“Ornithology… was a totally useless subject, the amateur’s field par excellence, largely ignored by even non-utilitarian academics.  No one entered it expecting to be given money and no one, for sure, had ever emerged with any.  Yet… it was here that organised natural history was to accomplish its greatest feats…. its secret lay in numbers.  Birds had a breadth of appeal that no other branch of natural history could rival” (Allen, cited in Adam, 2010, 11)

I’m cultivating LBB habitat and an interest in beetles.  In the meantime, there’s still the challenge of trying to figure out what the “obvious fauna” (Wilks, 2010, 288) are up to in my backyard.

For instance, what’s going on here?

Was there was a stash of sausages in this hollow in the pine tree to put that big smile on this kookaburra’s dial?   If so, they must have been those tiny party saveloys since she kept coming back for more.

Actually, kookaburras don’t subsist entirely on barbecue left-overs or snakes.  Insects make up a big part of their diet, and like magpies, they normally find food on the ground, dropping onto prey from a perch above so they don’t have to do any aerial acrobatics toting that great big kingfisher beak.

Given that birds usually feed in the leaf-litter, or in the sky, or in the canopy – they don’t usually mix it up – I’m not 100% sure this was actually snacking.  Like cockies and magpies, kookaburras are have stable, even “traditional”, territories guarded by the same breeding pair for years and years (Legge, 2010, 48).  And cackling away together isn’t the only way that kookaburra clans – pair-bonded breeding couples and their older offspring “helpers” – mark out their turf.  They also stake their claim with some mid-air show-offery.

Sarah Legge describes one such bit of border policing, a “bellyflop display”: “a single bird flies from a perch to another tree 5-20 metres away in a graceful swoop that ends with a flared landing on the lip of a hollow.  It pauses there momentarily, then swoops back to its original perch”.

Sounds pretty familiar, though I didn’t see a rival posse of bellyfloppers in action today.  Maybe my kookaburra was getting in shape for a big flopping battle down the track.   Or maybe she was really was scarfing saveloys…?  Without photographic evidence, who can say…?

Another of this week’s mysteries: what makes this poor benighted tree the most delicious in the neighbourhood?

After our recent visits by black cockatoos, I wondered if that this scarified specimen might be host to  wood boring larvae that are said to appeal to the yellowtail palate.  I’ve come to suspect that proper ornithologists share the bird watching punter’s lack of interest in bugs, since descriptions of cockatoos’ preferences are ubiquitously vague –  the sites I’ve consulted all comment tersely that yellowtails like “some insects”.  Thanks for the detail, guys.

Mind you, maybe this vagueness is a result of the fact we’re all so “meh” about bugs we can’t even be bothered giving them names.  David Wilks notes, for instance, that a survey of just four types of eucalypts in Western Australia recently identified more than two thousand species, most of them unknown (Wilkes, 2010, 288). I reckon we’re well overdue for a PR campaign to sell us on cute, quirky and cuddly bugs. And there is one!  Manu Saunders is trying to spark up a month long celebration of “Arthropod April” … though thinking about it, we may need “Arthropod August” as well…

If I couldn’t identify the mystery larvae, I had no trouble working out the true culprit in The Mystery of the Tortured Tree:

Is this sulphur crested cockie digging out one of those 2,000 species of unnamed critters?  Does the bark of this specimen have a particularly good mouth-feel, that buttery consistency that just says “bite me“?  Or is this just the local flock‘s agreed upon spot to hang out and have a beak manicure?

Okay, there’s no bird identification challenge here, but I reckon there’s still plenty of secrets to be told in big boofy bird psychology.

References

Adam, Paul (2010) “The study of natural history – a PPP” from Daniel Lunney, Pat Hutchings and Dieter Hochuli (eds) The Natural History of Sydney, Royal Zoological Society of New South Wales

Kaplan, Gisela T. (2004) The Australian Magpie: the biology and behaviour of an unusual songbird, CSIRO Publishing

Legge, Sarah (2004) Kookaburra: King of the Bush, CSIRO Publishing

Recher, Harry F. (2010) “A not so natural history: the vertebrate fauna of Sydney” from Daniel Lunney, Pat Hutchings and Dieter Hochuli (eds) The Natural History of Sydney, Royal Zoological Society of New South Wales

Wilks, David (2010) “A hotbed of biodiversity? A natural history of the Ku-ring-gai council area” from Daniel Lunney, Pat Hutchings and Dieter Hochuli (eds) The Natural History of Sydney, Royal Zoological Society of New South Wales