About Me

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Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Wednesday 26 September 2012

Bored? Ah Frigate, Let's Catch a Bird...

It would be fair to say my flabber was gasted by this story this week. Briefly, it laments the apparently imminent passing of the 'hobby' of frigatebird catching on the Pacific Island of Nauru. The closest it comes to explaining why it happens is when the subject of the story, a Mr Gioura, one of the last practitioners, tells us that the captured and tamed birds are sent out to sea - to bring more frigatebirds back... It's not for me to question others' cultural practices, but it does sound like a symptom of too much spare time and no internet connection.

I have read elsewhere however that some Pacific islanders have traditionally used tame frigatebirds to carry messages between islands (though having reported that, I'm not too sure about the status of written languages in pre-European Polynesia). Even without such drastic measures as those advocated by Mr Gioura, frigatebirds have become accustomed to humans and their scraps around ports.
male Magnificent Frigatebird perched on the fish market roof, Puerto Ayora, Galapagos

As for the birds themselves, they are close to being the world's ultimate aerialists, far more at home on the wing than on land or water. The Magnificent Frigatebird of the American tropics may have a wingspan of close to 2.5 metres, to carry a weight of just 1.5kg; this gives them probably the lowest wing-loading (weight carried per area of wing) of any birds. All flying birds shed as much weight as possible, with hollow bones, but a frigatebirds has carried this to a wonderful extreme - its entire skeleton provides just 5% of its entire body weight! By contrast the great flight muscles make up a quarter of its overall weight.

Magnificent Frigatebird silhouette, Galapagos.
The long forked tail and the very long slender wings are the keys to its aerial virtuosity.
Frigatebirds are famous - or infamous - for their piracy, when they use their extraordinary aerial power and agility to harass terns and boobies coming back to the breeding colony to disgorge their load of fish. They are indeed very good at it, but really they work for an honest living most of the time, seizing fish and squid from the sea surface. Perhaps appropriately, they are especially partial to flying fish.

Some places in tropical and near-tropical Australia are particularly good places to enjoy them (if you're not a tern). One is Lady Elliott Island, north-east of Fraser Island, where they roost in trees around the shore near the sole resort.
Greater Frigatebirds (male above, female below), Lady Elliott Island.

Another is Weipa, a bauxite mining town on the west side of Cape York Peninsula, in far north Queensland. Here the birds swoop down thrillingly to drink from the flooded tailings dams at the edge of town. I reckon this is one of the most exciting bird experiences in Australia, but it isn't widely known.
Frigatebirds, both Greater and Lesser, drinking at evening, Weipa.
Males of all five species inflate their remarkable throat pouch, which is an adapted air sac, normally a key part of a bird's breathing system, in courtship displays. Sadly this one wasn't interested in impressing me.
male Magnificent Frigatebird, Puerto Ayora, Galapagos.
To finish, I have an abiding memory of the frigatebirds at Weipa, scores of them hanging nearly motionless high above the mangroves, drifting on the air until darkness took them. And I've never had the least inclination to catch one...

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