18 Apr 2014

Red-backed x Isabelline Shrike hybrid – Dhahran Hills

Whilst birding the ‘patch’ on 13 April I came across an interesting looking shrike. The bird looked like a hybrid between Red-backed Shrike & Turkestan Shrike to me and was a very striking bird. I took a few photos and sent an e-mail containing the pictures to Alan Dean who is an expert in hybrid shrikes, asking him for his thoughts. He very kindly replied with the following details:
“Yes, it certainly looks like a hybrid between Red-backed Shrike and ‘Isabelline Shrike’. Given that it has a broad (even though diffuse) supercilium, it might be concluded that the Isabelline Shrike form involved is Turkestan (phoenicuroides) and collurio x phoenicuroides is the commonest form of hybrid.  However, this may not be certain. The bird appears to have quite a lot of grey interwoven into the upperparts – paler grey than is typical in phoenicuroides  – while the forehead is pale and the loral bar diffuse. This could just be the outcome of hybridization (which doesn’t always produce quite the appearance we might expect) or perhaps ‘karelini’ input but it’s conceivable that Daurian Shrike (isabellinus aka speculigerus) is involved. This is a less common hybrid with collurio but does occur. There are photos of a somewhat similar bird from the Chuta Steppes in Evgeniy Panov’s book ‘The True Shrikes of the World’, though that has less-marked supercilium and a peachy (rather than collurio pink) tinge to the underparts. Turkestan is most likely the ‘other’ parent but I wouldn’t regard this as absolute”.
Lars Svensson kindly added the following: “As you say, very difficult to know the outcome of hybridization, which it clearly is a case of here. I thought this bird was particularly interesting in that it for once (among such hybrids) showed a decent amount of collurio characters. To me it is a real toss a coin situation whether phoenicuroides or isabellinus is the other parent.”
Magnus Hellström mentioned the following: “Establishing the ID of the non-collurio parent beyond doubt is of course difficult, but like Alan I would find phoenicuroides a more likely candidate. I find the scale of colours in this individual rather different from the one shown by hybrid birds in the area of isabellinus x collurio hybidization (Altai/NV Mongolia), and more consistent with hybrid birds seen further west (e.g. Kazakhstan).”
Brian Small mentioned: “I tend to agree with Magnus and Alan in getting a feeling that phoenicuroides is involved.”
These hybrid shrikes are not uncommon in the overlapping breeding zones of Red-backed and Turkestan & Daurian Shrikes and various examples, including ‘karelini’ types have been seen in the Eastern Province of Saudi Arabia over the last few years. I would like to thank Alan, Lars, Magnus and Brian for commenting on this very interesting hybrid shrike.






6 comments:

  1. Smart-looking bird, whatever its' roots, thank God for digital photographs i could'nt imagine trying to submit some field notes with such subtle colouring.....

    Laurie -

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  2. Laurie,

    Long time no hear! Certainly was an obvious one compared to many we get here. Although it lookes quite like a Red-backed Shrike, I am yet to see a RBS this year and they are normally arrive 31 March / 1 April.

    Jem

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  3. Great bird Jem and good identification comments.

    Cheers

    JanJ

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    1. JanJ

      Thanks - nice to get such informative comments from people with substantial knowledge of these types of birds

      Jem

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  4. Yeh - sorry 'bout that Jem, i still check yr blog every day, some of the periphal WPal sites are the only things that keep me going in a British winter. Will get back to commenting more frequently - out looking for Ring Ouzels locally today....

    ATB Laurie -

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    1. Laurie

      Good luck with the Ring Ouzels. A bird that has occurred on my 'patch' but one I have not seen - an extreme rarity in the Eastern Province of Saudi Arabia.

      Jem

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