Sunday, 25 September 2011

Greater Painted Snipe

Female (centre) and two males


Just a quick blog tonight, with a few photos from our latest trip to Tarangire, where there seemed to have been a fairly major influx of Greater Painted Snipe along the river and down at Silale. I managed a few photos for a group that were by the German Bridge and thought they'd be a good prompt to remind people about some of the interesting things about these birds.

Obviously, they're nomadic, moving around wetlands across Africa. In fact, the species has a huge range across Asia and (though some people split the species) into Australia, and in very few places are they ever resident, wandering around according to processes as yet undertermined. Which means, of course, they're always worth keeping an eye out for!

And, of course, they rather famously have reversed sexual dimorphism - the female is the brighter of the two, with the male being rather more cryptically coloured, a trait the share with their rather closely related Jacana cousins. (The similarities to common or African snipe are due to convergant evolution.) Thus in the top picture the nice brigtly coloured female in the centre is flanked by two males. And as you'd expect in such cases, parental care - both incubation and care of the chicks, is left to the males, whilst after completing laying of the clutch (usually around 4 eggs) the female goes on to find another male to mate and lay with. It's interesting to puzzle about why this response to polyandry may have evolved  - the only birds that have it all belong to Charadriformes, and it's most developed in a few tropical species. Worth puzzling over, as scientists haven't solved it yet either! Let me know if you have any ideas...

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