Their song, though melodious, is very unimaginative compared to that of a Song Thrush or Blackbird. They just sing very nearly the same phrase over and over again.
The pair of Great Crested Grebes that I photographed yesterday are building a nest on the northeast corner of the island, a new place for a grebes' nest. It is sheltered by the baskets of water plants and might be safe from gulls, but it doubt whether the water is deep enough to deter the Grey Herons that nest on the island. The baskets make a picture almost impossible, and I got this bad shot by holding the camera at arms' length above my head.
From this early stage in construction you can see what a Great Crested Grebe's nest is like: a haphazard mass of twigs, leaves and algae heaped on top of a projecting branch or root. Once built, it continuously slumps down into the water and has to be added to every day to keep its top above the surface.
The Bearded Tits had again flown to the reed bed at the east end of the Serpentine, in much of which it is hard to see them. I waited for a quarter of an hour before a small brown bird flitted between the reeds, and then it called and it was a Wren.
Here a Coal Tit in the leaf yard enjoys a pine nut that I gave it. Pine nuts are their natural food; they prise them out of the cones with their sharp little beaks. The German for a Coal Tit is Tannenmeise, 'pine tit'.
And this is yet another pigeon colour, the pale brown variation called 'isabel'. Of the two pigments responsible for feather colours, the black one, eumelanin, is strongly reduced here, and the reddish one, phaeomelanin, is normal. The pattern is normal too, with the two wing bars of the original wild Rock Dove and the iridescent feathers around the neck.
The name 'isabel' for pale brown is said to drive from the behaviour of Queen Isabella I of Castille. In April 1491, when King Ferdinand II of Aragon besieged her city of Granada, she vowed not to change her underwear until the siege was lifted. It ended in January 1492. Later, despite her resentment and probably after changing her underwear, she married Ferdinand.
I'm quite unschooled in these things and am intrigued by the reference to the Grebes, the Herons, the gulls and the water depth. Would it be possible to expand on the theme? I imagine it's to do with eggs, young or food supply but it's not immediately apparent to me how the water depth is significant? Grateful for anything else you feel able to add.
ReplyDeleteA Great Crested Grebe's floating nest needs to be anchored to a branch in sufficient depth of water to keep a Grey Heron from wading out to raid it. It also needs to have some protection overhead to stop Herring and Lesser Black-Backed Gulls from raiding it from above. The site behind the baskets is probably sufficiently obstructed by the baskets and overhanging branches to keep gulls out. But I doubt whether the water is deep enough, since it is right at the edge of the island. An earlier nest in the middle of the east end of the island, attached to a tree branch farther offshore, has been attacked by herons in at least two previous years.
ReplyDeleteThat said, grebes do succeed in raising young in unsafe places. But the odds against them are worse.
Thank you. Interesting and enlightening as usual. It's a tougher life for a Grebe than I imagined and my sympathy for the Heron is fast fading. I once saw a Heron being mercilessly chased by a gang of crows into the Bayswater Road hedge and felt for it, being picked on by the bulliers, but now I suspect it wasn't hanging around in their territory just to take the air.
Delete