Academic in the Department of Zoology, and one of our visitor engagement volunteers in the Museum, Dr Tony Fulford writes:
Pirates, pirates! Other garden birds take refuge when a gang of starlings descends. Gangling, long-legged, short-tailed and sharp-billed they strut about at twice the speed of other birds, dominating the bird feeders and forever squabbling.
There has to be more to such a gregarious, lively, gypsy of bird than a bird-table bully.
Opinions are divided. Even their appearance has us in two minds. The plumage is gothic dark and oily, or iridescent deep purples and greens flecked with a thousand stars. They arrive mob-handed but where have they come from? There’s a romance to these itinerant strangers who leave as suddenly as they arrive, but a comforting familiarity to the one on the wall shaking its wings as it wheezes and pops its way through its silly song.
The jumble of clicks and descending whistles of the song can sound muddled and chaotic to our ears but, as is so often the way with birdsong, slow it down and extraordinary intricacy is revealed.
Starlings make full use of both sides of their syrinx (birds’ double-barrelled equivalent of our larynx) to develop two voices independently.
So where do they come from? Africa is home to the great majority of Starling species (over 50), many brilliant blue, green or purple, some long-tailed, others with strange dangling wattles. Most are highly gregarious and garrulous. Iridescence seems to be a theme: colours generated not by pigments but by diffraction caused by the microscopic structure of the feathers. Our Common Starling is not itself a sub-Saharan species (though it has been deliberately introduced to South Africa) but reveals its African origins by its moulting strategy. Generally juveniles of birds of temperate regions only moult their body feathers shortly after leaving the nest, retaining their flight and tail feathers for a further year, while Starlings, in common with most tropical passerines, undergo a complete post-juvenile moult.
It’s not uncommon for 50 or more individuals to turn up in our small garden at once. While they more than hold their own at the feeders there isn’t room for them all there. The rest do what comes most naturally to them: they stride about the lawn plunging their closed bills into the grass then opening them to prise apart the stems and roots in the hope of discovering a tasty insect down there. At this time of year parents bring along their grey-brown fledglings who scamper around after them begging noisily to be fed. They aren’t yet strong enough to feed in the grass, although they do try.
At this time it is particularly noisy in our garden because a tradition has developed for many Starling parents to corral their dependent young in a crèche in the overgrown hedge out the front. (Jackdaws, another gregarious passerine species, also crèche their young like this.) The other day the adults there had lost their usual cockiness and were alarming and flapping in panic. They’d noticed a Carrion Crow taking a predatory interest in their fledglings. It takes a lot of squabbling to maintain social cohesion but this is where it pays off: that crow was no match for a gang of angry Starling parents.
No account of Starlings’ social behaviour would be complete without mention of their murmurations. At dusk in winter from November onwards Starlings cruise around the countryside gathering in huge flocks. Large groups may drop down to water for a quick drink and wash before bed but their ultimate destination is often a reed-bed, a safe roosting site difficult for land-based predators to penetrate. Locally, reed-beds at Wicken Fen, Lakenheath and Fowlmere are favoured spots were tens of thousands of birds put on kaleidoscopic displays: the flock swoops and whirls gathering in number while they decide where to settle for the night. As they gather they utter a special, short rallying call.
Inevitably, a few birds among the thousands need to relieve themselves so each whoop over the reeds is followed a second or two later by the plitter-platter of droppings. Suddenly when the collective decision has somehow been made the birds pour like water from the sky to be absorbed by the reeds. Once in the reeds a cacophony immediately develops as each bird fights for the best roosting perch – the Starlings are squabbling again!