Headed to Llyn Penrhyn and the RNG was showing really well from the mound but was getting chased all over the gaff by a juv GC Grebe. It was doing some mega long distance underwater diving to escape. I heard a few Water Rail squealing and realised one was sat in a willow tree overhanging. Not seen that before.
this lokks like a very good candidate to me especially that 3rd picture - what a bill. The below is taken from Garner's book.
ReplyDeleteAdult winters obviously have the four contrary features to first winters as mentioned above i.e. wholly dark iris, obvious white spur at rear of cheeks and crown, clean white secondaries and more obvious crest on rear crown. Once aged, adult winter holboelli is variable but some have dark cheeks almost concolorous with the crown. On typical European birds there is a more tripartite pattern to the head with blackish brown crown slightly paler grey brown cheeks and white throat. The most important feature is the bill colour, which appears to normally be yellow only at the base in European birds, and more extensively yellow on the lower mandible in Holboell’s. Although it is very subjective the bill of adult Holboell’s often looks to me obviously thick and long with the lower mandible dominating and seeming to overlap the upper mandible.
Cheers
Marc