Three hours later I'm back home with some good news. Of the 87 tit boxes on site, 26 had active nests with eggs, an occupancy rate of 29.8%, which is about average. The number of eggs in the boxes ranged from 1 to 12, and all appeared to be either Blue or Great Tit.
Blue Tit incubating
Clutch of 12 eggs!!!
There was only one box with an adult sitting, (Blue Tit), and none of the other eggs were being actively incubated, so most of the clutches were incomplete. Given an incubation period of about 14 days, the first chicks should be hatching in mid May, and be ready for ringing a week or so later. I was on my own today, so I didn't check the owl/Mandarin boxes. All the boxes checked will be entered into the BTO's Nest Record Scheme.
Away from the boxes, the site was quite quiet today, with most of the resident birds appearing to have settled down to breeding as well. Both Great-crested Grebe nests are still being incubated, as are the Moorhen and Coot nests.
As far as migrants are concerned, there were about 10 Swallows over the top reservoir, along with my first House Martin of the year. Willow Warblers, Chiffchaffs and Blackcaps were also singing around the site, but no sign of any Pied Flycatchers yet.