They don't fly south for several months. Perhaps they were young ones?
Swifts usually leave soon, staying a few months only to breed. We saw a few yesterday.
See https://www.rspb.org.uk/birds-and-wildlife/house-martin .
Simple QRP projects, 10m, 8m, 6m, 4m, FT8, 160m, WSPR, LF/MF, sub-9kHz, nanowaves and other random stuff, some not related to amateur radio.
See https://www.rspb.org.uk/birds-and-wildlife/house-martin .
I saw one swallow in early April and none since. I have not seen a single house martin or swift.
At one time these were common, but not any more. This may in part be the wind direction, but I suspect global warming: their food supplies on their long journey north may have reduced as deserts grow.
To me, seeing screaming swifts overhead is an English spring and summer. Perhaps for not much longer?
Every few weeks I take a peek at the narrowband activity on Oscar 100, the geosynchronous satellite. My own view is activity is patheticall...