Marsh Warbler (isn’t it?) Spurn 1st June
1st June 2010 produced classic drift conditions at Spurn…
Light easterlies with sea mist produced a (prob 1st summer) Red-breasted Flycatcher as well as a singing Icterine Warbler and 3 Red-backed Shrikes. One bird that stayed below radar for most of the day was an ‘odd Reed Warbler’.
This bird has sparked some controversy and provided an opportunity to learn. Ringed early morning on 1st June as ‘oddly plumaged Reed Warbler’. Biometrics seemed to eliminate Marsh but the plumage suggested Marsh. It went down as a Reed. Fortunately it was re-trapped in the early evening and having missed it in the morning (I have an interest in any ‘odd’ plumages!) I was glad to get a chance to see it. The plumage was pretty amazing – amazingly Marsh Warbler-like being virtually wholly olive over the upperparts, especially the rump, no brown/ warm/ rusty tones and with off white underparts and lemony yellow streaks and wash. The rather long-looking primary projection has pale grey tipped primaries.
Final verdict? Marsh Warbler! While the birds’ measurements didn’t fit with data in the classics ringer’s manual, ‘Svensson’ they did fit in with other studies on Marsh. I contacted some ringers with plenty of Marsh experience from Shetland and found them all gathered in the same place. Roger Riddington, Steve Votier and Paul Harvey were happy to call it a Marsh Warbler. Lesson Learnt? Don’t rely too heavily on marginal biometrics when it comes to ID of some species! See below: