During this last year of the Atlas, I'm trying to fill a few gaps and it's clear that nocturnal species particularly tend to be under-recorded. For Tawny Owl, for example, there is a large hole in central-north Lincolnshire in which they have not been confirmed as breeding, extending from east Scunthorpe to Grimsby and south to Tealby and Binbrook. (The grid squares are SK99, SE90, SE91, TF09, TA00, TA01, TF19, TA10, TA11, TF29, TA20.) Tawny Owl presumably breeds in every one of these. For this species (though not some others), it's not so bad further south in Lincolnshire but there are gaps in coastal squares TF57 and T58 for example - real or not?
In the past few days I've upgraded two squares from absent to possible but it's beyond one person's ability to confirm every one. There must be birders who live closer than I do to these squares and who could pop out (dusk and, especially, pre-dawn are the best times) and find them. And are there any ringers monitoring boxes in these areas?
There are other poorly recorded nocturnal species - and of course plenty of diurnal species where gaps in the Atlas are obvious. So this is a plea for lots of effort to boost recording of breeding evidence this spring & summer. To see what's missing near you, look at 'My local gaps' and 'Priority squares (breeding)' on the BTO Atlas website and also check recent entries on the Lincs BTO blog
http://btolincs.blogspot.com/Andrew