"Jack Harrison" wrote in message
...

"Michael McNeil" wrote
Perhaps these birds are first broods? I presume they
breed in both countries?

Strangely most migratory species that come here in summer don't breed in
Africa during our winter, but only breed after northwards migration.

Jack



The advantage of this being the extra day length that they get in Northern
latitudes combined with plenty of food also which enables them to raise up
to three broods.

JP