Dipper: We were lucky to watch a Dipper feeding near Ashford-in-the Water this week. These passerine (perching) birds have many specialist adaptations to make them aquatic, unique among passerines. Their dense feathers and large preen-gland makes them especially water-proof, while their haemoglobin count is high, giving them sufficient oxygen for long, active spells underwater. They also have nasal flaps which they close, and white, nictitating membranes (third eyelids) that protect their eyes when underwater. This makes them look unusual if you catch them with their ‘white
eyes’ when above water (see photograph). While they sometimes feed from rocks and in shallows, their main way of feeding is to walk rapidly along the bed of a fast flowing stream, wings spread wide for stability, picking up invertebrates, small fish and insects. Their name comes from their habit of bobbing when standing, not from taking a dip! Conditions: Mild, cloudy day. Temperature: Max 12- Min 10c.