Nature Notes

Jenny Dixon

Wharfedale Naturalists Society

wharfedale-nats.org.uk

MOST of them have now arrived, our summer visitors: sand martins at the Ben Rhydding and Ilkley nest sites, house martins in our friend’s Addingham stables, swallows glimpsed skimming the fields, and chiffchaff, willow warblers and blackcaps in full song. I’ve also heard that pied flycatchers and redstarts have returned to Strid Wood. Cuckoos have been heard on Beamsley Beacon and Burley Moor, though I haven’t yet had any report of one on Ilkley Moor. Still – any day now! The dawn chorus is building up to its full complement.

And – breaking news! Swifts, usually the last to get here, have been seen dashing high above Ilkley Cemetery. Their arrival announces “Summer”. They swoop low into town, screaming a derisive greeting and then dash off again to climb the sky where we can just detect their characteristic scythe-shaped silhouettes as they hunt insects unbelievably high above us. What a star turn! Earth-bound creatures that we are, it’s hard to imagine what their lives are like. They come here to breed, to reap the benefit of our long hours of daylight for gathering food for their young. They are monogamous and return to the same nest site each year. Their nests are put together in holes in buildings and they lay only two or three eggs. The time taken for both incubation and fledging is variable: swifts depend on the weather. They’ll fly long distances to find food. The eggs have evolved to survive a cooling period of long parental absence that would kill other birds’ young, and nestlings just have to learn to wait! That’s not all. Once the fledgling steps from its nest it doesn’t touch down till it returns to the breeding site, probably one or two years later. Everything – feeding, sleeping, mating – is done on the wing. Their legs are, not surprisingly, stubby and weak, though they do have strong feet to cling to stony surfaces.

The other late arrival to look out for, rather rare here in Wharfedale now, is the spotted flycatcher, a robin-sized brown bird with an upright stance and an easily recognizable method of hunting its food. It perches on a post, rail or tree branch, flies out and up, often in a quick spiral, catches an insect with an audible snap of its beak and returns to the same perch and a repeat performance. They often nest close to houses and are quite confiding. In 2015, a pair reared four young in a roosting pouch tucked under my sister’s garage roof.