25th August

Nobody can complain that today's rain was unexpected, but it more than lived up to its billing with approaching an inch falling overnight and through the daylight hours before the clearance eventually came late in the afternoon. Efforts on the land were always hampered by the conditions but it did look as though, at least by way of passerines, next to nothing new had made landfall. The sea got plenty of attention and after a slow start a limited passage developed off the Bill, where the final totals included 17 Common Scoter, 13 Manx Shearwaters, 11 Balearic Shearwaters, 10 each of Great Skua and commic tern, 4 Whimbrel, 3 Arctic Skuas and singles of Common Gull and Arctic Tern.

Hopes of the change in the weather perking up immigrant moth activity were largely dashed, with a Latticed Heath at Sweethill the only noteworthy overnight capture in the traps.

We receive constant gripes that we rarely feature ageing and sexing tips on the site these days. We've never actually made a conscious decision not to feature them but they do take a quite a while to put together and most likely time's just been at a premium and they've simply fallen by the wayside. By way of a limited resurrection on a duff day for other news we've got together a few images from the last few days of the two age classes of male Redstart (photos © Martin Cade):

We're not at all sure that many birders appreciate quite how uncommon adults of the vast majority of the routine migrants are at migration watchpoints like Portland: put simply, adults are much too clever/experienced to make the mistake of stopping off in the suboptimal habitat of a godforsaken, barren and windswept headland like ours; without a lot of checking back we can't quantify the precise ratio of adults vs first year Redstarts in autumn but the adult male featured above was the first one we can remember handling for several years.

The most obvious pitfall with adults is assuming - wrongly - that the brown tips to the greater and median coverts are an immature feature; these feathers, at least when fresh, are always to some degree brown-tipped, and it's the basal edges of the greater coverts that should be checked - grey in adults, brown in first years. Our first year bird also shows a very typical moult-contrast in the greater coverts: the outer 8 or 9 feathers are juvenile, whereas the innermost 1 or 2 with an adult-type pattern have been replaced prior to migration during the post-juvenile moult.

The difference in tail shape between the two age classes (typically, adults have broader, more rounded-tipped feathers than first years) is maybe not so obvious in Redstart as it is in many of our regular migrants, but the two tails above do show rather nicely the much better quality of the adult feathers when compared with the poorer quality - already very worn and chipped at this early stage of migration - of those of the first year.