20th April

That's more like it. As has so often happened in the past, migrants moving in a clearish sky but into a brisk and chilly northeasterly dropped in some quantity on reaching the coast, with the Bill the focus of an arrival of c400 Willow Warblers. The feeling is that spring here's running a week to ten days later than the recent average so variety wasn't as good as might have been expected as we enter the final third of April: Wheatear, Chiffchaff and Blackcap all managed 50ish totals at the Bill, where the back-up cast of 4 each of Tree Pipit and Redstart, 2 Pied Flycatchers and singles of Yellow Wagtail, Whinchat and Garden Warbler (the latter the first of the spring) was really pretty paltry; a few more of the same elsewhere, together with 2 Jays and a Ring Ouzel at King Barrow and the first small arrival of Dunlin at Ferrybridge, did however make for easily the most productive land birding of the spring to date. Overhead passage was either disappointingly weak in comparison with the riches on the ground or, perhaps, largely overlooked: hirundines and finches - the latter including a couple of Siskins - were certainly dribbling through but the numbers reported were far below what might have been hoped. Given the conditions nothing was expected of the sea and a lone Great Northern Diver and a handful of Manx Shearwaters and Common Scoter were all that was logged from watches at the Bill.

A nice male Bar-tailed Godwit amongst the slightly improved wader numbers at Ferrybridge © Pete Saunders:

Ageing Pied Flycatchers in spring is always something you have to be a bit cautious with since they're one of a limited tranche of passerines that have a pre-breeding season moult that can create contrasts in several plumage tracts that can easily be mistaken for similar contrasts introduced by post-juvenile moult - for the non-ringers amongst our viewers: put simply, adults usually moult their whole plumage after the breeding season so their feathers are of uniform age, whereas most youngsters moult only some of their plumage so have a mixture of young and adult-like feathers; a limited range of passerines - like Pied Flycatcher - sneak in another partial moult before the breeding season and because both adults and first-summer birds do this both age classes might have a mish-mash of old and new feathers at this time of year.

Our two Pied Flycatchers today were thankfully pretty straightforward and both were youngsters born last summer. Females are trickier than males because their plumage is that bit drabber but, even on the closed wing, you can just about make out the old brown-edged, juvenile outer greater coverts...


...more telling though was the tail: few if any of the tail feathers are renewed in the pre-breeding moult so the normal pattern for a youngster would include quite well-worn and faded outer feathers like we can see on the left side of our bird's tail; however, the outer feather on the right side is very fresh and adult-like with a conspicuous broad white rim - we're guessing this feather had been accidently lost during the winter and replaced with one with an adult-like pattern.


The male was easier to age as a youngster: quite apart from being conspicuously plastered with grey-brown plumage above...


...and having a very heavily worn tail...


...absolutely diagnostically, the faded outer greater coverts had conspicuous pale tips - had these have been adult feathers they may well (since they'd already be six or more months old) have looked a paler black than the new glossy inner feathers but they'd have only had, at the most, very inconspicuous pale rims. Also visible on the open wing is a single renewed innermost secondary - this is not an age-related feature but a quirk of pre-breeding moult in some but not all Pied Flycatchers that renew this and maybe some other inner secondaries © Martin Cade: