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:
15th May 2000. Monday was a hot day, up to 27 Celsius in the nest box. Here is the male at the nest box entrance.
And here is the female ejecting some detritus from the nest.
The male and the female have been feeding the chicks in waves, at an average rate of one feed every five minutes or so (76 feeds from 9.30 am to 3.30 pm, and 79 feeds from 3.35 pm to the last entry at 8.44pm). A spate of around 5 feeds is followed by an extended absence of both parties from the nest box, or an extended nest maintenance session and a short brooding interval by the female. Here is the female warming the chicks - scarcely necessary, one would think, on such a hot day.
We now understand why last year's family was not successful. The male last year was much less in evidence than this year's male. Also, the female, last year, spent a lot of time fluttering her wings at the male, inside the box, in a courtship feeding ritual. This year, the pair bond is much stronger. No fluttering rituals have been seen; the female appears to take her male for granted. She does, however, from time to time sing for him inside the box, doing a little dance with her upper body. This we did not remark last year.
The male is sharing the feeding trips equally with the female, but she also has the nest maintenance and hygiene services to carry out. Every now and then she takes time out to stand aside, adjusting her feathers and cooling off her underside from sitting on the hot chicks.
When the partners are both in the box, they pay close attention to the brood.
The chicks are more demanding of food now. They are larger. They wriggle around on each other jostling for position to present their growing beaks. In a few days they will be large enough for sensible pictures.
Meanwhile, the oak leaves have burst and there seems to be no shortage of caterpillars. The male does not seem to have the measure of the tiny chicks, presenting them forcefully, time and again, with monsters.
The weather is forecast to change tomorrow.
16th May 2000. Today is much cooler, only 16 Celsius at 6pm. Our birds are keeping up their workmanlike job of regular feeding. The female has been sitting on the chicks every three feeds instead of every five feeds observed yesterday. This is probably to keep them warm in the cooler weather. Nevertheless, the adults provided 99 feeding trips in the six hours before sunset. This is an average of one trip every three and a half minutes or so. The chicks are noticeably larger and all seven beaks have been seen waving around at the same time.
The nesting instinct must be very strong in these creatures to keep them working at this rate for what will probably be nearly three weeks. Steven Pinker, in the book "The Language Instinct", gives the following quote.... To the broody (bird) the notion would probably seem monstrous that there should be a creature in the world to whom a nestful of eggs was not the utterly fascinating and precious and never-to-be-too-much-sat-upon object which it is to her.
Our female bird has kept up her little dancing performances at the entrance to the nest box (on the inside, looking out). The male, on the other hand, is a no-nonsense bird, taking only a moment or two to deliver his cargo of caterpillar to the hungry mouths, and not then hanging around for social chit-chat with his mate.
17th May 2000. The weather has certainly changed. At 6pm it was only 11 Celsius outside the bird box and there had been heavy cold showers during the afternoon. Our birds press on, regardless. And in a consistent manner. From 7am to 1pm there were 113 sorties for food; then during the rain showers, from 2pm to 8pm there were a further 115 trips. The birds are bringing a variety of food now, not just caterpillars. One large round spherical object was stuffed into a gaping beak, much to the consternation of the little chick, who gagged several times before the watching parent removed the obstacle and tried again. The second time the chick managed to swallow it whole.
The picture above shows the somnolent chicks, in post-prandial digestion mode after a heavy feed. Below, we show the parent arriving in a hurry with the next course.
If you want to see what these chicks really look like, close-up and in colour, take a look at David Jones's splendid picture posted on his web site.
18th May 2000. The nest of chicks is hotting up. At 10pm the temperature differential between the nest-box thermometer and the outside air was 5.3 Celsius, up from the more normal 2.5-3.0 Celsius we have observed recently. Possible, because they take up more room, they are spreading the heat around. An adult bird's body temperature is reported to be 41 Celsius.
19th May 2000. Professional feeding activity. Here is a picture of the parents and chicks, during "quality time".
The chicks are still difficult to distinguish one from another.
The mother spends time wallowing on the brood.
She also spends a lot of time burrowing into the bottom of the nest cup.
Finally, here are the eggs at the top of the previous page, hatched into 1-day-old chicks. The box had been blown sideways by the squalls and showers; it was straightened up and the picture stolen in between bird visits.
email d.jefferies@surrey.ac.uk David Jefferies 19th May 2000