The year I was born, 1981, signified the last twitchable Orphean Warbler in Britain. Rather a lot has happened since then, including the split of the species into two - Western (hortensis) and Eastern (crassirostris). I've seen both abroad on a number of occasions, and must admit I have struggled to see hard and fast diagnosable differences in the field. Yeah, perhaps hortensis are warmer looking birds overall (especially on the rear flanks and undertail coverts) but getting them singing is the best way forward. Unless you trap one and that's what happened at Hartlepool earlier this week...
Western Orphean Warbler - WOW
Identified as a Western, based on its bill length of 16.5mm (hortensis 15.3-16.9mm and crassirostris 18.0-22.1mm per Shirihai's book). Of the previous 5 records, the first bird at Portland was identified to today's species level as a Western Orphean Warbler on the basis of a tail feather left with the record that has subsequently been DNA'ed. While the Scilly bird in 1981, looking at photos, also seems to be a Western Orphean Warbler. No idea about the other three though.
Right, that's it and looking forward to the long weekend and hopefully one more mega out of this spring.