Date: 3/20/17 9:59 pm
From: 'Phil Unitt' <unitt...> [SanDiegoRegionBirding] <SanDiegoRegionBirding-noreply...>
Subject: [SanDiegoRegionBirding] Baltimore Oriole in La Jolla
Dear friends,



Among the bird specimens I received at the San Diego Natural History Museum last Thursday from Project Wildlife was a female Baltimore Oriole found in the Bird Rock area of La Jolla on 15 March 2017. I prepared the specimen today (SDNHM 55000) and found on dissection that it was an immature (no discrete ova visible in its ovary even with a hand lens). The back was boldly dappled with black, each feather having a black center and a broad orangish edge. This pattern transitioned into fine black speckling on the nape and head.



A perhaps still more notable specimen received in the previous batch was a Fox Sparrow of the very dark subspecies townsendi found in the recently developed urban sprawl between Sorrento Valley and Carmel Mountain on 10 October 2016 (SDNHM 54998). This subspecies breeds in the rain-forest zone of the Alaska panhandle and does not normally migrate as far south as southern California. It is one of the “sooty” Fox Sparrows but is conspicuously darker above and more heavily and darkly spotted below than the usual medium brown subspecies of this flavor we have wintering around San Diego. It’s the color of 100% cacao—no milk in this chocolate. Only one specimen of Passerella iliaca townsendi has been collected in San Diego County previously (near Descanso in 1924), and no specimens have been reported from Baja California. I found on the Internet this map



(https://commons.wikimedia.org/wiki/File:Leapfrog-migration_Passerella_iliaca.jpg)



illustrating the leapfrog migration of some of the sooty Fox Sparrows, first described by Harry Swarth in 1920in his landmark paper on the Fox Sparrow. The details of the ranges depicted aren’t too accurate, but you can see the concept.



Thanks very much to Linda King for her continuing help as liaison between Project Wildlife and me. As you can see, even if the good folks at Project Wildlife are unable to save a sick or injured bird, the specimens can contribute notably to our scientific record.



Good birding,



Philip Unitt

San Diego


 
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