Friday, March 19, 2010

The swifts are back on their nests

For many years, now over thirty years ago, I studied the colony of Pallid Swifts in the attic of the Gibraltar Museum. Last year we put two infra-red cameras on two of the nests. Here are some photographs from one of the nests from the night before last. Although the Pallid Swifts have been about since the beginning of February, it is only now that they have started to come close to the colonies in the evenings and visiting the nests.

The adults return to the same nest, which they repair, year after year. They do so for over twenty years in some cases. Many Pallid Swifts raise two broods in good years, the last young flying in October. In contrast, Common Swifts in Gibraltar only raise a single brood.

Only the female visits the nest at first and sleeps on it. The males sleep on the wing. In time the males accompany the females at the nest and they take it in turns to incubate and feed the young. We shall follow these nests all spring and see how successful they are this year.

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