Swifts on the move? - NOT amateur radio

Yesterday we went  for a nice walk around the sleepy village of Reach, near Cambridge. Although there were swifts around, there are fewer. At least some have started heading south. 

Screaming swifts in the air are a sound of late spring and early summer in the UK. Sometime in August you just realise they are not there. It will be next April or May until they (hopefully) will be back again.

See https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/swift/ .