Скачать или смотреть Great Crested Grebe nesting-exhange at Utterlev Mose

This 5 minute video from a lake-marsh several miles northwest of Copenhagen, called "Utterslev Mose," captures the nest/incubating-exchange "ritual" between a pair of Great Crested Grebes. These are about the most amazing waterfowl in Denmark. Their courtship displays, in early Spring/late winter, includes paddling hard on the surface of the water in a dancing synchronization, as if dancing on water, with clicking bill "kissing."

Due to their very sought-after head plumage, which became a major fashion for hats among women of the mid 19th century, they were almost hunted out of existence in Europe. In the UK, for example, by 1865 it's estimated there were less than 100 of them left.

To the music of Vivaldi.

At about minute "00:40," the Baroque music stops, to bring you directly into the female Crested Grebe's POV as she incubates her brood. The camera let's you experience the host of things she experiences from her environment... other birds... people walking by in the background. She also by cares a bit for her nest, and you see four eggs. The breeding pair often only care for 2 young a season, each parent taking one of the newborn on his or her back, to begin teaching how to be a Grebe Anyways, there's then a sequence with mysterious hissing out of view, which source I only reveal after that scene.

At about minute "02:49" begins Vivaldi again. Since the mates instinctively will shy away from a nesting-exchange if people or other dangers are nearby, to avoid attracting attention to the nest, I'd been patiently been sitting there very quiet for about an hour, waiting for her partner to arrive. It's often hard to tell the sex of these birds, but the male often has a bit more head plumage, and the female's brood patch, to incubate, is more prominent. The first time he arrived, I'd gotten up to stretch, and though I captured him on film, he dived down, came up near where I was, and made a huge splash to distract me from the nest. Again, instinctive behavior. Then he was gone for almost an hour more.

And when he returns, Vivaldi begins again.

Like many birds, grebes will pattern a lot of their mate-interactions by the nest, and a lot of other behaviors, into movements that easily can be anthropomirphiucally interpreted as ritual dances, and for a good reason. It's a way to "remember" patterns of behavior that have proven successful over the course of natural selection. And his swimming dance, back and forth around, with coordinated quirky head movements, as he's about to change places with his mate on the nest to continue incubating the eggs, is hypothetically a way to both get a view of what's going on around the nest, including me (now that I've posed no danger for nearly 2 hours), and to distract potential predator attention to the eggs from that vulnerable bit of time when one gets off the nest, and the other gets on.

It's easy to miss, but at about minute "04:20" the male, having now swum back and forth around the nest a few times, with his mate on it each time the camera follows him go by the nest... well, suddenly the nest is empty of her, and the 4 eggs are visible. You can even see my own personal double take of that moment from behind the camera. With my zoom lens concentrated on following the male's dance on the water, you briefly experience the lens flip back to the nest as it follows the male, my double take. She's gone! The nest is vulnerable. Then the dance continues, but his mate's dived under.