Spring-like weather last week has given way to bitingly cold easterly winds. Despite there being clumps of wild narcissus in flower in sheltered places and some almond blossom, we are still in winter here. Despite the arrival of House Martins and some Swallows, and even a Great Bustard starting some tentative paces in its courtship display, the birds too still have a winter feel about them. Hard weather in central Europe has brought an invasion of Goosanders to Spain and two have even reached Extremadura, for the first time ever. I saw a female swimming on the river running through the Monfragüe National Park last Sunday. But the most striking feature of birds in winter are the sheer numbers. Yesterday we watched a big flock of two or three hundred Corn Bunting rising from a stubble field as a male Merlin attacked. It had arrived almost un-noticed, mimicking a Mistle Thrush with a low gliding flight interspersed with rapid flaps. Then it accerated and dashed through the rising buntings,twisting and turning, swerving upwards. It did not manage to take a bunting - I am sure had we not been there, it would have dived for a second attempt. At the weekend I took part in a national survey of winter roosts of Herons and Egrets. A tiny clump of rather undistinguished willows in a tiny gravel pit, beside a road has been a roosting site for Cattle Egret, close to one of my favourite birding routes. I arrived late afternoon. There was nothing in the trees and just half a dozen egrets were feeding around some sheep. As the sun set, parties of Cattle Egrets started to arrive from all directions, mostly flying low and direct, some coming in from greater height and then tumbling down to land. They gathered on a small hummock next to the trees (see the photo) before taking some mysterious cue which made them take off and then literally stream into the trees, which become something of a swarming white, squawking mass. I estimated somewhere between 2250 and 2400 Cattle Egrets had arrived, along with over a hundred Little Egret and a single Glossy Ibis, which is a very unusual winter record. As the results came in from across the province, it became clear that this roost was by far and away the largest.