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Female Caspian Stonechat

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  • Female Caspian Stonechat

    Having spent a week in Kuwait, one of the many highlights was great views of quite a few male Caspian Stonechats variegatus, but only one male Siberian maurus and one male European rubicola and one possible male Armenian armenicus.

    Amongst the males were several females and I felt given the preponderance of male variegatus that these females were likely to be of this form too. The views they gave were excellent and confirmed what I had noted at Tring, that they show no white at the base of the tail in field views and therefore are indistinguishable from maurus.

    I checked 'Stonechats' (Urquhart and Bowley, 2002), but this caused me a bit of confusion as the description and illustrations show quite prominent white on female variegatus. However, my images from Tring suggest this not to be the case and also this series of fine in-hand photos (and comments) from Israel tends to back up my feelings - http://nubijar.blogspot.com/2011/11/...tonechats.html. Yoav Perlmann says,

    'Females are much more tricky. In the field, the tail of this individual would look completely dark, and would be identified as maurus. However, when the uppertail coverts are moved aside, the white bases to the rectrices (about 10 mm) become visible. This of course is impossible to see in the field. This female seems to fit variegatus too; I'd expect armenicus to have less or no white at the bases of the rectrices. For this reason I believe that many of the European records of 'maurus' females in fact involve variegatus. It would be interesting to compare the ratio of variegatus VS. maurus records in W Europe for males and females.'

    Are there any other in-field photos of definite Caspian Stonechat females showing white in the tail? I would be really happy to see them, but if my suspicions are correct, what does this mean for extralimital records of female 'Siberian Stonechat'?

    Brian S
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    Last edited by Brian S; February 20th, 2012, 10:35 AM.

  • #2
    Great Brian

    have you checked the primary projection and the wing-tip : UTC tip ratio??

    very nice matter and thanks for that !

    See you soon in Sicily in April

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    • #3
      Hey Andrea

      Good to hear from you my friend. I hope you have that Rock Partridge in captivity ready to release for the group!

      That should be

      Ciao

      Brian

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      • #4
        I got back from a trip to Egypt last weekend, and with the Red Sea dripping with migrants on 6th April found three Eastern Stonechats at Lahami Bay - a male and two females. I suspect the male is a decent armenicus candidate but it seems that despite decent shots the females are only diagnosable as armenicus/maurus/variegatus. Shots are at http://rothandb.blogspot.co.uk/2012/...tonechats.html.

        I also like Yoav's suggestion, in Brian's first link, about how quickly we're labelling in the field autumn birds as maurus...

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        • #5
          Rich

          An interesting series of images, with the last female showing the amount of white at the case of the tail that I would expect a female variegatus to show - I may PM you to get permission to use this in an article Yoav and I will be working on. As to your males, I am not sure that I would assign this to a categorical armenicus, variegatus is notably variable in the amount of white visible compared with the black and this is also affected by the amount the tail is opened. For example watch my video of these males - http://www.surfbirds.com/forum/showt...ll=1#post38497 - especially the last.

          I have lost my measurements of the black at the tail tip, but will post them when I find them.

          Brian S

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          • #6
            Thatīs a great piece of film Brian!
            Showing well the care to be taken.

            Also a few her by Daniele (maybe the same trip?)

            http://www.pbase.com/dophoto/kuwait2012&page=all

            JanJ

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            • #7
              Originally posted by Brian S View Post
              An interesting series of images, with the last female showing the amount of white at the case of the tail that I would expect a female variegatus to show - I may PM you to get permission to use this in an article Yoav and I will be working on. As to your males, I am not sure that I would assign this to a categorical armenicus, variegatus is notably variable in the amount of white visible compared with the black and this is also affected by the amount the tail is opened. For example watch my video of these males - http://www.surfbirds.com/forum/showt...ll=1#post38497 - especially the last.
              Thanks for the reply, was kind of hoping you'd come back with something Brian. I've seen a few of these birds in Kuwait on three winter trips, and was pretty aware of what I imagine you would call 'classic' male variegatus such as this from JanJ's link. I must admit that, having seen some variability in the field of variegatus, it's intriguing to know just how variable this subspecies really can be - I have always gone on the basis that if there's less than a quarter of the tail base pale, and that a male shows next to no white in an open tail then it'd probably be an armenicus. I guess that this view is simplifying things somewhat - and I'd love to know how variable variegatus is - and perhaps birds such as the male I photographed in Egypt are best put down as variegatus/armenicus...

              By all means, you or Yoav can drop me an email/PM.

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              • #8
                It makes you wonder what armenicus is.....?

                Brian

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                • #9
                  Originally posted by Brian S View Post
                  It makes you wonder what armenicus is.....?

                  Brian
                  Indeed, and I'll be genuinely interested in seeing what you and Yoav come up with on this topic. Variegatus - perhaps the clue is in the name...

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