BITTERNS and more BITTERNS. With the freezing conditions of the past week, Buckinghamshire has experienced an influx of this reed dwelling species, with 2 birds at Willen Lake, 2 birds at Weston Turville Reservoir and 2 birds at Calvert BBOWT Lake. At least two more are at Tring Reservoirs, just over the county border in Hertfordshire. Mark Stirland took these fantastic images above.