[SBB] Kumlien's at Milpitas?

["Jeff Poklen" <[[email protected]]>]

Yesterday, 25 Feb. Lois Goldfrank and I went to Hidden Lake in Milpitas, Santa Clara County to find the Kumlien's-type gull reported by Alvaro Jaramillo on Tues. 22 Feb.  Alvaro's gull was present but so were, as it turned out, two other pale Kumlien's-type gulls.  These were mixed in with lots of 1st and 2nd cycle Thayer's  --all in different stages of molt, bleach, feather wear and patterning (typical 2nd cycle messiness), which made for a challenging situation, to say the least.  We spent the whole time studying, mulling, separating and comparing.  

I took a number of photos, which I've since uploaded to my computer and edited.  I've managed to isolate three individual gulls which might be perceived as contenders for Kumlien's but two of these are probably just pale  Thayer's.  I've posted 12 of these on my website at http://www.pbase.com/jpkln/milpitasgulls.

Earlier I expressed "little doubt" that Alvaro's gull was a Kumlien's.  However, after yesterdays exercise in perception, that little bit of doubt has grown somewhat.  Gull 1 (on the Milpitas Gulls page), has already been  described on Alvaro's website at http://www.birdsofchile.com/iceland.htm.  Regarding Gull 2, notice the large eye, dove-like head, are very similar to Gull 1.  Notice, also, that the eye color is slightly darker.  Its bill is a bit more petite, parallel-edged and not as thick at the gonys giving it a slightly longer and/or thinner-billed look than Gull 1's which is more bulbous-tipped by comparison.  The mantle may be a slightly darker shade of gray but the light can play tricks as the Gull 1c photo illustrates.  Its primaries are pale beige with paler, frayed fringes.  Overall structure, size, short-leggedness, primary projection is similar to Thayer's and to Gull 1.
 
Other people, including Lois and myself, were confusing Gull 2 with Gull 3 as they were constantly changing position and setting us all back to square one.  However, with the photos before me, it didn't take long to separate these two.  It appears Gull 3 differs from Gull 1 and 2 more than these two do from each other.  Notice Gull 3's slightly thicker bill and more pronounced gonydeal angle.  Also, this individual "feels" to be slightly larger and chunkier compared to the other two.  A different bird altogether.  Probably a male Thayer's.  Its eye, like that of Gull 2, is slightly darker than Gull 1's. 

According to K. M. Olsen's Gulls of North America, Europe and Asia, 10% of 2nd cycle Thayer's can have a pale (bicolored) eye, whereas 2nd cycle Kumlien's eye is "normally pale".  Interestingly, on my Kumlien's Gull page at http://www.pbase.com/jpkln/kumliens, one can see that 4 out of 8 individual 2nd cycle birds have really dark eyes and 4 have pale eyes  --and notice that Gull 1's eyes are not quite as pale as the eyes of these latter 4.  

Of all the Kumlien's Gulls I observed and photographed in Newfoundland, it seems to me that, on the whole, the primaries of 2nd cycle birds, if colored, generally appeared beige-gray or gray centered and were cleaner looking than the primaries of Gull 2 & 3, which are more typically a Thayer's-like beige.  Although I can't find any reference to white-primaried 2nd cycle Thayer's in my limited library, I'm sure it's not out of the range of possibility 
--especially judging by the many pale Thayer's with bleached primaries present at Hidden Lake. 

Seeing and reading about Gull 1 in isolation on Alvaro's webpage was one thing:  impressive and definitely suggestive of Kumlien's.  Seeing it in the context of many similar-looking gulls, two of which could be and were occasionally confused with Gull 1, was a whole other ball of wax.  One was forced to look long and hard.    

I hope others will feel free to weigh in with their opinions and impressions about these gulls.  Please post to SBB and/or MBB so we can all share.

Jeff Poklen

Santa Cruz, CA
[[email protected]]




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