Swallows (Barn) - NOT amateur radio

At one time, these were a common summer migrant bird wintering in South Africa. They usually arrive here early in April.  In 2021, I only saw 2 all year. 

Swifts are also meant to be getting rarer, but we seemed to have similar numbers here to previous years. I have yet to see a single swallow here, which is very late. In the past, they were common by now.

My son, who has been wild camping, has seen and heard several cuckoos, but no swallows. Times, they are a changing...

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