Friday, 12 January 2018

The Great GM Mealy Redpoll Controversy

There's been a discussion raging in Greater Manchester (GM) for the last week or so about a little bird that's turned up at Elton Reservoir in Bury.  The bird is definitely a Redpoll, but is it the rare Common or Mealy Redpoll or just the more usual Lesser Redpoll we often get at this time of year?

I went twice to see this bird, the first time with no success and then today when I had good views of it for a decent length of time.  The bird is certainly bigger and paler than the other Redpolls which are present, although a couple of the other birds are quite pale too.

Unfortunately it was very difficult to get a photo of this bird when it wasn't on a Nyger feeder and the light was poor on both occasions that I visited Elton.  But hey, you get what you can, while you can.

It was also great to meet local birder Steve Higginbottom and the original finder the bird, along with Paul Wilson. Steve has provided and hung all the feeders at Elton and stocked them with food out of his own pocket.  We had a long chat about lots of things and on my second visit I made a small donation to the costs of the food - without the feeders being there we probably wouldn't have noticed this slightly different bird.  Well done Steve!

Opinions were certainly differing on a number of Facebook groups where I posted my photos with some strongly in favour of it being a Mealy Redpolls and others stating quite categorically that it was a Lesser Redpoll. A bit of research has told me that this species has only recently been split away from the Lesser Redpoll and the whole issue of whether it is actually a separate species is still being debated.

I asked for help in making a decision on the UK Bird Identification Facebook group and the well-known birder and rather controversial Lee Evans replied with the following two comments after seeing my photographs and video:
An apparent adult male MEALY REDPOLL in plumage but you have to beware of bleached male Lessers as spring advances. Mealy generally have more feathers about the tibia and cloaking on the nape but I don't see any of that here
 After seeing the video I posted (included below), Lee went on to say:
Definitely a male MEALY REDPOLL in this video. The nape feather cloaking is apparent in the image

No matter what you think of Lee, he does have a lot of experience and generally knows his stuff, so I thought I'd cracked it.  But the saga continues ...

I also emailed Chris Batty who is the Lancashire representative at Rare Bird Alert and a member of the British Birds Rarities Committee (BBRC) for his thoughts too.

Here's his reply:
Hi Martyn,

Thank you for your email regarding the Redpoll at Elton Reservoir although I regret I haven’t seen the bird myself.

Looking at the photographs and video of this bird I would identify it as a Lesser Redpoll based on my experience of migrating Lesser Redpolls in Lancashire in spring that I have handled that closely resemble this bird – one such bird is attached. I have measured the wing lengths and tail lengths of the birds I have trapped for ringing and they consistently fall within the parameters of Lesser Redpoll and outside Mealy Redpoll. In the redpolls males are bigger than females, and males are paler-faced than females. I am not aware that a greater extent of red is a pro Mealy Redpoll character. 
In the Elton bird I think the absence of any white on the mantle away from the two central ‘stripes’ is a negative character for Mealy Redpoll. However, I’d be interested to be proved wrong and the most conclusive way for someone to do this would be for them to trap the bird and measure the wing and tail. If someone can do this then please do let me know the measurements.

All the best,

Chris Batty, RBA

P.S. Of course the revelation that the DNA off redpolls is indistinguishable across species limits strongly suggests that the birds themselves can’t distinguish between Lesser and Mealy
So, what do I think? Well it's certainly larger and paler than all the other Redpolls I've seen but it's probably just a variant of Lesser Redpoll. So unfortunately that's one life and year tick I'll need to rescind, unless the GM rarities Committee decide otherwise.

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