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Battle in the Garden

Every year at around this time our back garden becomes the site of an aerial battle. Let me explain. There is a hole under the eaves of the house that is a prime piece of ornithological real estate. Early in the year a pair of starlings, part of the large local population, move in and settle down to the business of raising a family. But then later in the spring, a pair of swifts arrive with the objective of securing the nest site for themselves. This is when the trouble starts.

In previous year there have been extended 'dog fights' between the starlings and the swifts. It's amazing to watch, with the two birds testing out their very different flying skills. The swifts are fast and incredibly manoeuvrable but the starlings have a very effective ambush tactic, knocking the swifts out of the sky as they swoop in to try and enter the nest. It's got pretty nasty in the past, and on one occasion I have had to rescue a grounded swift – they aren't able to take off on their own if reach the ground. While the battle has been quite spectacular, it also clear how high the stakes are. If the starling brood is forced to fledge too early it could easily be lost, and the swifts risk not getting a nest site. Or worse, if a swift is grounded when the local human is out, and the neighbouring cat isn't…

In previous years the stand off has been resolved. Shortly after the start of the battle, the starlings have fledged and the swifts move in unchallenged. They then provide us with several weeks of aerobatic entertainment as they come and go from the nest. Later in the year, after the swifts have left, the starlings will move back in, raising a second brood.

This year has been different. With the coldness of the early spring the starlings didn't start nesting until three or maybe four weeks later than usual. When the swifts arrived the starling chicks had only just hatched, as judged by the start of the parent birds shuttling in and out with beaks full of caterpillars. There has been an extended period of stand-off with the swifts persistently trying to claim the nest and the starlings defending it doggedly. On several occasions the swifts have disappeared, and we thought they had given up, only for the battle to resume a few days later.

Yesterday the persistence of the swifts was rewarded. The starlings left the nest, the young fledged, and yesterday evening both swifts entered the nest as the sun went down. After even more drama than usual, the battle is over for another year.