Wobbly Leo season

Another 5 BiggLuggs territories checked last night -
3 blanks & the 2 with contacts, were not telling me much.
After studying this species for 20 years I cant fathom out what accounts for so many consecutive poor or blank breeding seasons ?  (neighbouring Kestrel & Barn Owl all fine)
&
why the sudden exodus this winter of usually resident pairs....
Its clear some birds have not returned to traditional territories (some occupied since 1950's & presumably a fair while before)
This week generally sees the first eggs laid.
I know a few pairs are looking very likely to lay - but the years of confirming fledging for 40-50 pairs seem a distant memory.
#InDuskWeTrust