The Robin nest is doing great, 5 eggs have been laid, the fifth arriving this morning with a first sighting at 08:30.
Today a significant change occurred and the Female Robin, instead of being absent from the nest all day, starting to incubate the eggs. This signifies that no more eggs will be laid, we have a clutch of 5. I’ve read that the incubation should last 13 days, so this would mean the first eggs hatching on the 29th June.
I’m really enjoying watching my first Robins nest and seeing how it’s so different from the Great Tits and Blue Tits I’ve previously watched. I’ve said before that everything is happening much quicker, from nest building to egg laying but it was also interesting the way the Robin has kept away from the nest, keeping it hidden.
All of this illustrates the different strategy of a Robin compared to a Great Tit. The Robin nest is much more vulnerable, because it’s open, hence the speed and secrecy. Why does it nest in the open, or in this case an open nest box? well there are many more places to build a nest if you’re not worried about finding a location with the right sized entrance hole. Because it’s vulnerable, they’re quick and have fewer eggs, with fewer mouths to feed the young will get biiger and be ready to leave the nest much quicker as well. This is why the Robin lays 3-5 eggs compared to 8-12 for a Great Tit.
And if it all goes wrong for the Robin and the nest is lost, as it hasn’t invested a lot of time, it can build another nest and raise another brood. A Robin typically has more broods than the 1 or 2 of the Great Tit which takes its time over its large brood, in its super secure, hole entry, nest site. All the eggs in one basket compared to the nesting guerilla tactics of the Robin.
Fantastic.
The nest box condition at the end of the day (22:00) is shown below, the first end-of-day shot with the incubating female present.
Chatou Nature Blog 