Bird Watching (UK) - - Turnstone -

sub­or­di­nate. It is the way of the world. In the case of Turn­stones, the hi­er­ar­chies work them­selves out in var­i­ous ways. Dom­i­nant in­di­vid­u­als, in fact, are the least so­cia­ble, for­ag­ing in the smallest groups. Most other Turn­stones would ap­pear to avoid them, as they do their own thing. These top dogs will, how­ever, re­sort to what sci­en­tists call ‘klep­topar­a­sitism’, which is ba­si­cally just steal­ing. When an­other Turn­stone has lo­cated an ex­cel­lent source of food, they move in and bag it them­selves. These birds have small home ranges, be­ing kings of their own small cir­cle. How­ever, an­other, more in­trigu­ing out­work­ing of hi­er­ar­chies is that Turn­stones show very strong in­di­vid­ual feed­ing quirks. You might think that Turn­stones only turn stones, but in fact they have six dis­tinct feed­ing A trip to the coast is in or­der if you want to see a Turn­stone. They like rocky shores, as well as sandy and muddy ones. See them on rocks cov­ered with sea­weed, also along sea­walls and jet­ties. They’re present for most of the year – Cana­dian and Green­land birds can be seen here from Au­gust to May, those from North­ern Europe pass through in July and Au­gust and again spring and non­breed­ing birds could stay through­out the sum­mer.

meth­ods, of which stone-turn­ing is only one. The oth­ers are sur­face peck­ing, prob­ing the bill into a fis­sure or sub­strate, dig­ging, ‘ham­mer-prob­ing’ – which is prob­ing with vig­or­ous pecks, for ex­am­ple in try­ing to open the cara­pace of limpets and other shells – and, fi­nally, rout­ing. The last-named is the tech­nique of mov­ing sea­weed aside to see what is un­derneath; the birds of­ten do this by lean­ing down and bull­doz­ing the sea­weed away, as if they were in a rugby scrum. Rout­ing, it seems, is the most pro­duc­tive of all the Turn­stone’s feed­ing tech­niques, and where the habi­tat al­lows the tech­nique, in­di­vid­u­als com­pete for the right to do it. In ob­ser­va­tions of di­rectly com­pared duos of birds, where the two op­tions were rout­ing or prob­ing, dom­i­nant in­di­vid­u­als routed more than low sta­tus birds, sug­gest­ing that their so­cial sta­tus af­fected their feed­ing meth­ods. In­ter­est­ingly, when stone-turn­ing is com­pared to prob­ing, there was a sig­nif­i­cant dif­fer­ence be­tween the sexes. Fe­males turn stones over more of­ten than males do, which tend to probe in­stead. In most bird hi­er­ar­chies (although not al­ways in waders), males are dom­i­nant over fe­males in win­ter flocks. This could mean that, de­spite the fact that we as­so­ciate this bird so much with its dis­tinc­tive habit of heav­ing stones aside to ex­am­ine what is be­neath them, this tech­nique is ac­tu­ally one of the less prof­itable ones? In which case, per­haps we are call­ing this bird by the wrong name? The next time you see one of these birds on a rocky shore, per­haps you should say: “there is a flock of sea­weed-routers?” Catchy – prob­a­bly not.

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