California Has Two New Bird Species. One s in Your Yard Right Now.

California scrub jay | Photo: Ingrid Taylar, some rights reserved

California is home to two new bird species - and youve seen at least one of them hundreds of times. Ornithologists have determined that two widespread populations of the familiar Western scrub jay (Aphelocoma californica), one of the states most common birds, are different enough from each other to merit splitting the species in two.

Scrub jays along the Pacific coast will now be called California scrub jays, which will keep the Westerns scientific name, while the paler, smaller-billed jays in the far eastern reaches of the state are now officially referred to as Woodhouses scrub jay, or Aphelocoma woodhouseii.

The split was made as official - or at least as official as such things ever get - when the new species was added to the 2016 edition of the American Ornithologists Unions Checklist of North American Birds. The Checklist, which is updated every year, is regarded by both scientists and recreational birders as the authority on North American bird taxonomy, and its annual revision is anticipated avidly by birders.

But the split of the Western scrub jay into two species is no surprise: the Woodhouses scrub jay has long been considered quite distinct from its coastal cousins, and scientists have talked about calling the Woodhouses scrub jay a distinct species from coastal jays since at least the 1940s. And its unlikely that this years split will be the last scientific rearrangement for the scrub jay.

--

--

If you dont remember actually having seen a scrub jay of either species, youve almost certainly heard one. These raucous, engaging members of the crow family are anything but retiring. Heres a California scrub jay making its presence known in Santa Barbara:

Its not hard to tell scrub jays from their cousins the Stellers jay, which are the only other blue jays native to California: Stellers jays, known to science as Cyanocitta stelleri, have black heads with pronounced crests. Scrub jays of whichever species lack crests, and their heads are mainly blue up top, with a dark eye patch that can look either black or dark blue depending on the light.

The differences in appearance between California scrub jays and Woodhouses scrub jays are a little more subtle: Woodhouses are a paler blue overall, and are less likely to have a distinctive blue breast stripe - a necklace - than their coastal relatives. One of the more interesting differences between the two species seems to have evolved as a result of the birds different geographical ranges: coastal California scrub jays oak woodland habitat offers a steady crop of nutritious acorns, and the birds have evolved heavy, hooked bills that make short work of acorns tough shells. Woodhouses scrub jays live in the more arid interior, where pi on pines and junipers offer the most reliable source of food. Woodhouses have narrower bills, which presumably evolved due to the birds need to extract pine nuts from their cones.

Woodhouses scrub jay | Photo: Alan Schmierer, some rights reserved

That difference in geographic range is actually the easiest way to distinguish between the species. California scrub jays range from the environs of Seattle along the coast to northern Baja, with an outlier population in southern Baja. In California, they occupy the western half of the state, from the coast well uphill into the west side of the Sierra Nevada - the birds are common camp robbers in Yosemite National Park.

Woodhouses scrub jays are relatively uncommon in California: their population stronghold is in the semiarid mountain forests of the Colorado Plateau, with other big populations in the Texas hill country and mainland Mexico. Woodhouses scrub jays do range into Californias eastern edge on a regular basis; there just arent a lot of them here at a time. The consummate birder Kenn Kaufman has mapped the ranges of the two new species in his article on the split on Audubons website, and really the easiest way to tell whether the scrub jay in front of you is a California or a Woodhouses is to look at the map and see whether youre in Woodhouse or California territory. Unless youre in the stretch of desert between Reno and Carson City, Nevada, the map is pretty much a slam dunk.

Kaufman points out that the abundance of each new species in parts of the west is a boon to those birders compiling life lists, an acquisitive hobby whose practitioners can make Pok mon Go players look like pikers:

Birders who have traveled widely in the West have probably seen both of these already, and will net an automatic armchair lifer from the decision. If you've already seen them, you can go ahead and count them

This isnt the first time ornithologists have split off new scrub jay species. Field guides once listed both the Florida scrub jay and the Santa Cruz Island scrub jay as members of the California scrub jay species. Both were declared to be separate species in 1998. And this current split between California and Woodhouses scrub jays may not be the last: some experts have suggested that some scrub jays from southern Mexico may merit being declared a new species as well.

Theres other news of interest to California birders in the 2016 Checklist: the Leachs storm-petrel, a small, dark seabird with a wide distribution in the Northern Atlantic and Pacific, has had two new species split from it: the Townsends and Ainleys storm-petrels. Both new species nest on remote islands off the Pacific coast of Baja California, making it possible that Southern California birders might see them. But distinguishing the new species from the much more common Leachs storm-petrel and from each other is extremely difficult, so its likely that this new split will vex birders.

And a name change of a one of Californias most prominent birds wont make much difference to birders, but will probably delight classicists.

LINK:	https://www.kcet.org/redefine/california-has-two-new-bird-species-ones...
	See more stories from kcet

Most recent headlines