White-tailed Eagle (Haliaeetus albicilla)
This is a dramatic bird. With its vast bulk, outsize bill and imperious manner of flight, its very presence brings electricity to the birdwatching experience, and panic to potential prey. When a wetland area is overflown by a White-tailed Eagle, every bird near and far flies up in alarm, and mayhem reigns.
By Jacob Spinks from Northamptonshire, England – Sea Eagle, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=37128730
A fate which any waterbird would want to avoid is to be ground down to exhaustion by a White-tailed Eagle’s persistence. These huge eagles are dexterous enough to snatch prey from the surface of the water, so if they get into a position to isolate a swimming bird, they don’t strike immediately but keep it under surveillance until it begins to tire. The potential victim at first dives repeatedly, it usual method of escape from a predator; but the eagle can follow it underwater and can harass it every time it comes to the surface. As the quarry runs out of energy, so its hunter waits for its moment.
These large eagles don’t always opt for such harrowing tactics; in fact, they are inventive, adaptable hunters that veer towards the easiest option. They will, for example, often frequent abattoirs and fishing-boats for scraps, and they take a high toll of defenceless chicks at large seabird colonies. They are not above stealing food from Ospreys and other birds of prey, and they will wade into shallow water if there are enough fish to swim around their paddling feet.
By Karlo – Picasa Web Albums, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=10951487
Impressive and admirable though they are as hunters, nothing that White-tailed Eagles do quite matches the theatre of their courtship displays. Both sexes are very vocal when pairing, and both will make loud challenging call-notes, thrusting their head back and bill into the air as they do so, like outsize cockerels. Their aerial antics can be breathtaking. Both soar high into the air, but the male climbs a little higher. It then dives down to the female, which turns over and presents claws. If both are so inclined, the two birds interlock their talons and then plummet downwards in a series of spinning cartwheels until they almost reach the ground. At the last moment the sky-dance partners separate, and may soar up again to repeat the process – a royal couple at play.
From ‘Birds: A Complete Guide to All British and European Species’, by Dominic Couzens. Published by Collins and reproduced with permission.