Da Beers!

Da Beers!

Wednesday, June 11, 2014

Very early occurrence of Craveri’s Murrelets off San Diego (and can the end of the world be far behind?)


Gary Nunn, Paul Lehman, Barbara Carlson, and other top San Diego birders have noted the very early arrival this year of Craveri’s Murrelets (Synthliboramphus craveri).  Writes Gary:
Catching many seasoned observers by surprise, this very early calendar date pair of Craveri’s Murrelets Synthliboramphus craveri were passed off as Scripps’s Murrelets while being watched at close quarters aboard a pelagic out of San Diego on 07 June 2014. Steadfastly avoiding flight, the two murrelets paddled away from observers and did not reveal their characteristic darker underwing pattern. However the detailed examination of photographs, after the event, revealed all other characteristic field marks of this rarely seen enigmatic Southern California alcid visitor. Note the longer and thinner bill, with tweezer like mandible tips, the solid black face marking under the eye conjoining the chin, and the black colored spur on the breast side. In addition around the eye can be seen two very small white eye arcs, which I find from close up photographs are characteristic of this species. In general it is possible to see a small white fleck in front of the eye in many Scripps’s Murrelets. This white fleck mark is usually more pronounced in one individual in pairs that are seen together (I think there is perhaps a slight sexual dimorphism in the extent of white face coloration in Scripps’s Murrelets). No such mark exists on these birds, they show an evenly black marked face in front of the eye.
It appears these Craveri’s Murrelets are as many two full months ahead of the more normal calendar date of first occurrence in Southern California.

Photo by Gary Nunn
Paul and Barbara wonder if this is related to two different pairs of Scripps's Murrelets way north off Humboldt County during May, which is very early (and fairly rare) for that latitude.

Gary further notes that 2014 is "shaping up poorly for breeding seabirds in Baja in general with several species now documented to have abandoned nesting rookeries and islands."  He says "it all seems a bit awry somehow... we are also experiencing an early influx of several thousands of Elegant Terns [in San Diego] for example, which appear to have abandoned Isla Rasa in the Gulf of California."

Is this about a failure of food stocks in the Gulf of California?  And if so, what's the nexus (if any) to Global Climate Change?

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