Tuesday, December 11, 2012

ISR - Lesser Short-toed Larks 11/26

Our Birdfinders group had a decent showing of larks in the Ovda Valley on November 26th. The most numerous were Crested Larks and Eurasian Skylarks but there was also a smattering of more unusual species including Bimaculated, Greater Short-toed and 5 fly-over Temmincks' Larks.  The highlight, however, was a party of five Lesser Short-toed Larks which provided a rare opportunity to see them up close and attempt to get to grips with some of the salient features. Immediately I was struck by the apparent differences between birds within the group which seemed to involve much more than just individual variation. Two of them appeared larger, sandier and heavier billed than I'd expect in a typical LST Lark.  Two others always looked smaller, colder gray but still heavier billed than I'd expect to see in typical LST Lark, whilst the fifth looked sandy-gray with a smaller, stubbier bill and was more in keeping with how I'd expect LST Lark in Israel to appear. My assumption was that birds of the latter type refer to the local sub-species in Israel (Caladrella rufescens minor). 

In the Birds of Israel (1996) Hadoram Shirihai lists five different forms of Lesser Short-toed Lark as potentially occurring in Israel, though only one of these (C.r. minor) is regular. The others (heini, aharonii, pseudobaetica, and persica) are described as rare to very rare, or have not been documented in the country with any type of certainty, or as Hadoram writes - "further proof needed". 

I don't mind holding up my hands and reaching out for help on this one?! 

Lesser Short-toed Larks - sub-species uncertain, Ovda Valley, Eilot region, November 26th, 2012. The large bird at the rear was especially eye-catching with a large, bulbous bill (recalling Dunn's Lark), a distinct dark lore and warmer, sandier tones to the upperparts. The breast streaking was also distinct in the sense that it was 'spotted' rather than streaked on the breast sides. Two birds of this type were present within the group of five and could easily be picked out on the features described above.  The same bird is featured in the next three shots below. Could this bird refer to C.r. persica and is it feeding alongside a couple of heini/aharonii types?

Lesser Short-toed Lark (ref: four images below) - sub-species uncertain, but possibly the regular form occurring in Israel (C.r. minor. Ovda Valley, Eilot region, November 26th, 2012. Smallish bird with sandy-gray tones, and compared to the birds above, a relatively smaller, stubbier bill. The lore also looks plain creating a more 'open-faced' impression, all of these features being in keeping with what I usually expect to see in LST Lark, and thus contrasting with the larger, heavy-billed, dark-lored birds within the same flock.

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