The weather has been fine but very blustery today, the strong westerly wind stripping some fresh leaves and apple blossom. More swifts arrived this morning, though I still have only one bird visiting a box. Despite the large UK arrival yesterday the proportion of breeding swifts back at colonies may still only be about a quarter or less of last year’s number. Swifts assemble over time as David Lack observed in Swifts in a Tower and many others have observed since. No two springs are alike. But what does always seem to happen is that the breeding colony is more or less assembled by the last few days of May. After this they are quickly joined by the first arrival of non-breeding birds.
Our swift left the nest box at about 8am and I watched it drop, almost touch the lawn and rise quickly into clear blue skies. It fed for a while with our house martins but was quite quickly joined by one, two then three more swifts. They have been feeding high above the village for much of the day, sometimes almost hanging in the breeze. They dart left and right up and down swallowing insects as they plough into the wind. After a while they speed downwind again and repeat the process, remaining more or less faithful to the airspace above Gilling East.
The first day you can go out into the garden and see a swift each time you know that the breeding birds are assembling. It is a joy just to sit and watch these high fliers carving up the fresh air and occasionally, they will descend to low level to ‘scream’ past the eaves. I watched a down wind flypast this morning, the speed and accuracy of flight breath-taking. But at this stage of the season these flypasts are usually once or twice past before they rise back up high to feed. All too often you hear them scream on approach look outside and they are gone.
House martin diary
We now have two pairs occupying artificial nest cups. There is at least one other pair in the village. A few years ago it would have been hard to imagine such a paltry population. Why? We don’t know. There is plenty of mud by the beck but just like the swallows their populations are vanishing before our eyes.
To add some hope a couple of new birds arrived today, almost certainly first time breeders which hovered by the nests without perching. I watched the interaction today between the swifts and the martins. They feed together often, but crucially sound the alarm when predators are around. For example as our swift was about to leave its nest box the house martins were calling above in alarm due to a sparrowhawk going through village gardens. The swift would not have been able to see the sparrowhawk but aborted its departure until the martins stopped their warning. It is not an exaggeration to say that the martins might have saved our swift’s life.