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Staggered Hatch

Chicks at all different stages
Chicks at all different stages

It’s fascinating to see how birds and wildlife respond to a bad summer. Driving out of Dumfries yesterday, I passed a female lapwing with a brood of two day-old chicks at heel, wandering carefully through a recently mown silage field. Nearby, a flock of twenty full-grown lapwings looked on; one of the hotchpotch gangs of immature birds and non-breeders which drift around the countryside all summer. It was only after close examination that I saw the tiny little chicks at all, and it would have been easy to miss them.

On North Uist six weeks ago, there were lapwings chicks on the verge of fledging, and several youngsters were bouncing around with their wings up after what seemed to have been several days of practice. At the same time, there were some tiny chicks still darting around in the silverweed, and it seemed amazing that these youngsters were even the same species. A staggered hatch is one thing, but the little chicks I found in Dumfriesshire would not even have been laid as eggs by the time the North Uist birds were flying strongly on the wing, and this seems to have been the case for several species this year, grouse included.

There are all kinds of explanations for staggered hatches, and this year it almost makes sense to have held off rearing young until now; the habitat is much further on now than it was when the first clutches were being laid, and the undergrowth actually looks far more promising now than it did in May, when it was cold and grim.

Unfortunately, staggered hatches lead to chicks at such a wide variety of ages and stages that predation pressure often has more of an impact. When all the eggs hatch at once, the grass is filled with tiny chicks and the little waders can have a certain mass momentum which sees them through. When they hatch in dribs and drabs, there is always a brood at its most critically vulnerable stage, and studies suggest that predators are harder on young birds in years when the hatch is staggered.

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