The purple-crowned fairy-wren a loyal partner

Unlike his relatives who travel long and far to show off their colourful plumage, the purple-crowned fairy-wren chooses just one lucky lady.
By Australian Geographic October 16, 2017 Reading Time: 2 Minutes Print this page

IN THE BIRD world the purple-crowned fairy-wren (Malurus coronatus coronatus), with his bright plum-coloured crest, is the kind of partner you’d take home to your parents. Unlike other fairy-wrens he’s loyal to just one mate, likes a duet and never strays too far away from his chosen one.

Restricted to the tropical savannahs of far-north Western Australia, rather than by virtue of being regarded as a “decent bloke”, it’s likely that the purple-crowned fairy-wren stays loyal to a single mate out of convenience.

According to Anne Peters, an ornithologist who’s studied these particular fairy-wrens for almost 15 years at the AWC Mornington Sanctuary, “this is partly due to their rather special ecology: these birds are riparian specialists, which means they only live in strips of vegetation along creeks,” thus restricting their ability to traverse several territories to advertise to females.

Related: A guide to Australia’s fairy-wrens

And either way, a recent study conducted by Anne and her team found that the traditional way for a fairy-wren to advertise his suitability — by flaunting his gorgeous colours — doesn’t seem to be the “make or break” in the relationship for the female purple-crowned fairy-wrens. “The timing of the annual production of the purple-black breeding plumage does not appear to be an important signal of male attractiveness,” she says. “Purple plumage appears to be used between males to settle dominance and compete for territories.”

purple crowned fairy-wren

(Image Credit: Laurent Lermusiaux/Australian Wildlife Conservancy)

The female purple-crowned fairy wren doesn’t care much about size either. “Animals that experience lots of sperm competition because females are promiscuous have larger testes. Male fairy-wrens in the breeding season have some of the largest testes known from birds. In comparison, purple-crowned fairy-wren testes are much smaller due to lack of competition.”

Instead, the female purple-crowned fairy-wren prefers a mate who shapes up to be a worthy duet partner. “Not only do both sexes sing, but they also combine 50 per cent of their songs to form duets. From a playback experiment it appeared that duetting is important for cooperative territorial defence, when pairs coordinate their response very closely,” says Anne.

Related: The bird that weighs the same as a teaspoon of sugar

It’s this perky, indomitable nature that Anne likes best. But also, their inquisitiveness and how relatively tame they are. “One of my favourite moments of fieldwork was when I was quietly sitting on the bank of Annie Creek, amidst the Pandanus palms, observing some birds foraging, when one of the birds in the group, as it was hopping from Pandanus to Pandanus, made a brief stopover on top of my head before hopping along.”

purple-crowned fairy-wren

(Image Credit: Laurent Lermusiaux/Australian Wildlife Conservancy)