Sunday, 26 April 2015

More Arrivals . . . .

News from today, and Shibdon Pond this morning had a common sandpiper but not much else of interest, though a walk along the boardwalk revealed the scratchetty song of a Sedge Warbler, and Rob (G&B) later had a Reed Warbler as well.

Common Sandpiper at Shibdon Pond

At Far Pasture there's still no sign of any Grasshopper Warblers, but has had a recent influx of Garden Warblers with at least three pairs there this morning, probably more. No sign of the Mandarin which was still there on Saturday for its third day. Clouds of midges formed in the treetops around the car park.

Certainly enough food for insect eating migrants

Not a particularly good day with the camera, the garden warblers joined the blackcaps and whitethroat in this year's most uncooperative birds competition and record shots were iffy to say the least.

 
Garden Warbler at Far Pasture - best I could get 
At least this smart garden Greenfinch was better behaved.

 

I'm always fascinated by the way things in the natural world find a way to interact with each other to gain an advantage. Watching a repeat of The Nature of Britain yesterday threw up such a case, in how ants inadvertently aid the dispersal of gorse seeds.

The seeds themselves are of no interest to the ants but they come with a blob of a fatty yellow substance attached which the ants find to be a bit of a delicacy. Foraging ants stumble upon one of these seeds after they have exploded from the pods but the foragers tend to be the older members of the colony and their jaws are no longer sharp enough to cut the blob of fat from the seed, so instead they use it as a handle to carry fat and seed back to the nest, where a younger worker will snip off the yellow substance.

gorse seeds still in the pod
with yellowy attachment
But now the shiny smooth-skinned seed has nothing for the ants to hold on to and is just too big for them to grip in their mandibles, so it has to be left underground in the nest where conditions suit germination better than being left on the surface and will soon sprout away and grow into another gorse a good distance from the parent bush. Clever stuff.

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