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Last year's birds
Fluff roosts
Fluff is usurped

A truly excellent informative site about these birds
David Jones's site with nesting Parus caeruleus, about 8 miles away

Visitors since 5th May 2000:

Activities in the nest-box, May 2000.

27th May 2000. Another truly horrid day today, with the rain leaving (since yesterday) 21 mm in the rain-gauge. The temperature overnight dropped to 5 Celsius, but the nestlings are feathered now, and sufficiently large that they can keep warm with their own internal fires.

There was a brief period of blue sky and sunshine early in the morning. We took the camera outside. Here is a bird against the blue sky.

Here is the bird on the antenna wire, with breakfast in beak.

Here is the female bird, displaying her brooding patch - the region on her chest where the feathers are thin or missing.

Here is the female bird removing poo from the nest box.

Here is the male, perched on top of the nest box.

At bedtime, the mother only half-covers the nestlings. She lets them breathe and get up to their own games while she gets some sleep.

The local squirrels might present a significant predatory threat for our birds, but they can't climb up a sheer brick wall, fortunately. Here is one of their young offspring with a nut.

28th May 2000. Sunday. There are now only a few days left until fledging. The weather continues unsettled, with heavy showers and sunny spells. Here are the chicks in nest box 2.

We can now see clearly that the seven nestlings in box 1 are all coming along well.

Here is a picture of the mother with her nestlings.

The family are all together in the box, when an inquisitive young starling pokes a beak into the hole, causing alarm and consternation.

The youngsters are stretching and testing their new wings. Here is "Icarus", at full stretch and in his display mode. He had better not fly too close to the sun or the wax will melt and his feathers will fall out.

The feeding rate today has been substantially constant at around 40 trips an hour, plus or minus 5, over the eight hour observation period. The feeding proceeds, as before, in waves or spasms, interspersed with lull sessions. The female spends hardly any time now brooding the nestlings for warmth, and much less time cleaning underneath them.

If one assumes there is a 15 hour feeding day, from 5am to 8pm, then there will have been 600 trips during the day, altogether, which is in accord with David Jones's obesrvations. Whereas earlier in the growing stage, when the feeding trips were every 3-5 minutes, now they are every one-and-a-half minutes. Our best estimate of the total number of feeding trips for the brood of eight chicks is 8550, plus or minus 25 percent. That works out at an average caterpillar (or food package) intake of 1220 per offspring during the growing phase. This is significantly different from the quoted figure in one of the sources that says that each young bird consumes "5000 caterpillars" when being fed in the nest.

The nest box is therefore a "caterpillar-to-blue-tit" conversion factory. Remarkably efficient, too. I wonder if humans, being "top predators", land up having eaten any of these caterpillars, in a transmogrified form at the other end of the food chain. Shades of Ilkley Moor.

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