Saturday 19 October 2013

There was a loud rattling of Mistle Thrushes around the Little Owls' tree. Half a dozen thrushes were alternately scolding the owls and flying to a nearby rowan tree to eat berries. They were clearly making a racket just for the hell of it, as the owls had retired into their hole and were completely invisible.

The Coal Tit in the nearby leaf yard is getting more relaxed about being fed by humans.

It nearly landed on my hand, only sheering away at the last moment. A human hand is an unfamilar thing for a bird to land on, and very small birds like Coal Tits can't quite get their claws round a finger -- unlike Great Tits, which casually fling themselves down  anywhere and rely on their strong toes to keep a hold. Tits, like all passerine birds, have toes that curl automatically when the tarsus (the backward-facing joint on the leg) is flexed, so they only have to sit down to clamp themselves firmly in place. When they want to fly away, they stand up straight and their toes unclench.

With luck, the Coal Tit will learn the approach that Blue Tits use, which is to fly to your hand from end on and grab your fingertip before walking up the finger to take food from your palm.

This Common Gull was hanging in the breeze, waiting to grab some food that someone was throwing to the waterfowl. Since it was flying as slowly as it could, its alulae were extended. The alula is the little set of feathers attached to the bird's thumb, which acts as an aerodynamic slot, smoothing the airflow over the top of the wing at low speeds to avoid stalling.

It has rather dark legs for a Common Gull. The range of our local ones is from pale straw yellow through greenish to mid-grey. If you see a Common Gull with legs any darker than this, and with a reduced white 'window' on its wingtips, it's probably a visitor from Russia and worth noting.

A Cormorant was having  difficulty balancing on the end of a fallen branch sticking out of the water near the Serpentine island.

And one of the young Great Crested Grebes was waving a big yellow foot in the air to uncramp it after it had been folded up.

You really have to think to work out the geometry of they way their legs fold. When Little Grebes, which have larger feet in relation to their size, fold their legs, the tips of their toes stick out on either side of their tail.

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