"Bill Grey" wrote in message ,

Several years ago a friend of mine a keen ornithologist concerned
himself with the question of Pied Flycatchers migrating to West Wales,
at least as far south as the Swansea Valley. Four of us constructed.
45 nest boxes in all and installed them in a local wooded valley. The
entrance holes were blocked with demi john corks to prevent the blue
tits and great tits nesting. This was successful and after the corks
were removed, eventually 40 out of the 45 boxes were taken up by Pied
Fly Catchers. Before this it was thought they didn't come further south
than about Aberystwyth, mid Wales..

What time of the year were the corks removed to prevent the tits nesting
yet allow the PF's to do so?
Tina

Hi Tina, it was some time ago, about 30 years in fact, but If I remember
correctly it was after the end of April and certainly after most Tits had
nested.

I was only the "labourer" my friend was the expert.

BTW the RSPB eventually took an insterest in the little valley and the
"Cwm Clydach Reserve" was established. They were badgerded to take a look
at the place by one ouf our group of four, and eventually a representative
visited .he area he was convinced of its potential as a nature reserve


Thanks, very interesting about the corks which seems to suggest if tits are
kept out where PF are, they will use the boxes later.
Does not apply here as we have no PF's.
Tina

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