Western Scrub-Jay is no more

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California Scrub-Jay by Jerry McFarland via Flickr. From Woodhouse’s, note the extensive white line going well beyond the eye, the bright white of the throat flanked by the blue collar going nearly around the chest, whitish belly and vent, deeper blue to the upperparts, more contrasty mantle, and larger features (such as bill) and overall size (tough to judge from a photo).

In one of the most exciting annual AOU Check-list Supplements since I started taking interest in them almost a decade ago, Western Scrub-Jay (Aphelocoma californica) has been split into two species: California Scrub-Jay (A. californica) and Woodhouse’s Scrub-Jay (A. woodhouseii). Being Scrub-Jays, my favorite group of birds, this is a really thrilling occasion.

(Note: Michael Retter does his usual fantastic job at the ABA Blog summarizing the Scrub-Jay split along with the remainder of the taxonomic changes, some of which I hope to touch on soon. To see the actual supplement, click HERE. A worthwhile, if slightly foot-dragging, review on the three Western Scrub-Jay subspecies is advertised by Retter and can be found in the April 2016 issue of Birding).

The split of Western Scrub-Jay has been anticipated since 1995, when Florida Scrub-Jay (A. coerulescens) and Island Scrub-Jay (A. insularis) were split from Western. There was historical context for this anticipation, as from 1910-1931, the Western Scrub-Jay complex actually made up four species: California and Woodhouse’s Scrub-Jays, as well as the Blue-eared Scrub-Jay of Mexico (corresponding somewhat with Sumichrast’s Scrub-Jay, more below on that group) and the Texas Scrub-Jay.

In 2010, the initial proposal to split the species was rejected by the AOU Committee, with further research into genetic differences and hybridization needed. I recall this event as feeling fairly deflating, as even then, having only seen one Scrub-Jay, the genus Aphelocoma was nevertheless always in my thoughts as I longed for experience with its other members.

Following the rejection, further research by ornithologists (as cited in the aforementioned  Birding article by Dessi Sieburth) “suggest[s] that Woodhouse’s and California Scrub-Jays are more different [genetically] than previously thought.” Prior to the 2010 decision, research had also shown that these two species “appear to be more genetically different from each other than are the Island and California Scrub-Jays,” which makes sense when considering the split and the likely way in which Island Scrub-Jay speciated.

Six years later, the first entry in this year’s initial batch of proposals detailed the recommendation to split the two groups, citing the genetic study mentioned in the preceding paragraph in addition to a second study done in 2014, which dealt with contact zones and reproductive isolation.

The one glaring omission from all of this seems to be a further split of Sumichrast’s Scrub-Jay (a genetically and morphologically distinct subspecies of Woodhouse’s Scrub-Jay from Central Mexico), which the authors of this year’s proposal address:

With respect to the sumichrasti group (sumichrasti + remota subspecies), Gowen et al. (2014) confirmed reciprocal monophyly of mtDNA with respect to other woodhouseii individuals. The divergence between sumichrasti and populations of central Mexico is greater than the divergence between insularis and californica (Fig.1 below). In microsatellites, individuals of sumichrasti and southern populations of woodhouseii were largely assigned to different genetic clusters (Fig. 3E; Gowen et al. 2014). However, Gowen et al. (2014) did not assess populations close to the putative area of contact near Mexico City (Pitelka 1951). Despite compelling evidence that the populations in southern Mexico constitute a distinct species, there is insufficient information regarding reproductive isolation to recommend splitting the sumichrasti group at this time.

It is unfortunate that justice cannot be taken now, but we should be looking for Sumichrast’s Scrub-Jay to be split from Woodhouse’s Scrub-Jay in the next decade, if not sooner.

A fascinating point made here is the fact that A. californica and A. insularis are more closely related than sumichrasti and woodhouseii. Like that made above regarding the closeness of California and Island Scrub-Jays versus California and Woodhouse’s, this discovery is unsurprising when considering geography. Much of the range of Sumichrast’s Scrub-Jay lies south of the Mexican Transvolvanic Belt, a major geographic barrier that acts as a mechanism for speciation. A related, though not completely congruent example, can even be found within Aphelocoma, with Mexican and Transvolvanic Jays (A. wollweberi and A. ultramarina, respectively): Mexican Jay is found north of the belt, Transvolcanic Jay is found along it (a fascinating overview of Scrub-Jay speciation, centering on Island, Florida, and ‘Western’ Scrub-Jays can be found in this Neotropical Birds Account).

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Woodhouse’s Scrub-Jay by John Breitsch via Flickr. In scouring photos for this post, I found it to be fairly easy to pick out the Woodhouse’s photos from the more numerous images of California Scrub-Jay. In comparison to the California at the top, this bird is overall less contrasty. Note the duller and shorter white line, less extensive blue bordering the duller white throat patch, tan lower chest and belly, faint blue vent, less contrasty mantle, and overall paler blue upperparts.

So what is the significance of this split?

Scientifically, it does ornithological justice by clearing up an issue that has come to light with further genetic research: the fact that ‘Western’ Scrub-Jay is in fact paraphyletic. As the authors of the proposal note: “because californica and insularis are sister lineages, maintaining the status quo is inconsistent with the treatment of A. insularis as a full species (AOU 1995).”

Personally, the split provided me with my first armchair tick ever, a long-awaited accomplishment (I couldn’t think of a better species for it to happen with!). I first saw Woodhouse’s Scrub-Jay over a year before my first California (March 30, 2011 to July 26, 2012), but the likely specific differences between these two definitely crossed my mind when I laid eyes on my first Cali, adding significance to the sighting. My initial encounter with that species took place while driving from San Francisco Airport to Point Reyes National Seashore on the first day of my and my dad’s epic 2012 California adventure. I glimpsed the bird on the side of the road as we drove by (we saw more during the trip), an unfortunate occasion for a first look, as the exact location of roadside sightings is often next to impossible to track down. Luckily for me though, the bird was along a memorably beautiful stretch of road, and a little ‘scouting’ on Google Maps Street View last night appeared to pick up on that original location.

Birding-wise, we will have to learn to get used to two new names, but the benefit of that is that it keeps the name ‘Western Scrub-Jay’ reserved for discussions of the species complex as a whole (i.e. the “Sage Sparrow Complex”). Initially, a lot of us (myself included) will likely slip up and reflexively call an individual by the former name, but in the vast majority of cases, the birder will be easily understood based on geography alone.

I find it wonderfully fortuitous that I was able to put this website together just in time to cover this split, likely one of the two last species-level changes in this seemingly straightforward yet phylogenetically complex group. There is still much to be learned about these birds, especially those south of our border, such as Sumichrast’s Scrub-Jay, whose continued connection to Woodhouse’s is likely only due to this hole in our knowledge.

-Alex

In addendum: for a good map of former Western Scrub-Jay subspecies, see the sixth edition of the National Geographic Field Guide to Birds of North America.

References:

American Ornithologists’ Union [AOU]. 2016. Fifty-seventh Supplement to the American Ornithologists’ Union Check-list of North American Birds. The Auk. 2016. 133: 544-560.

The History of Bird Names in the American Ornithologists’ Union Checklists 1886-2000: Swifts through Creepers [Internet]. [2008 May 24, cited 2016 Jul 9] . Available from: http://darwiniana.org/zoo/AOUmenu.htm

American Ornithologists’ Union [AOU]. 2010. Fifty-first Supplement to the American Ornithologists’ Union Check-list of North American Birds. The Auk. 2010. 127(3): 726-744.

Sieburth, D. North America’s Scrub-Jays: How Many Species? Birding. 2016. 48(2):52-56.

McCormack, J., Maley, J., Cicero C. Elevate Aphelocoma californica woodhouseii to species rank. AOU Classification Committee – North and Middle America Proposal Set 2016-A. 2015. 1:2-6.

Willow Flycatcher and the Trials of Year Listing

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A territorial Willow Flycatcher at Ash Creek Open Space in Fairfield, CT. June 12, 2012.

I finally picked up my year Willow Flycatcher (Empidonax trailli) this morning. On July 6th. I’d spent multiple outings in the last couple weeks looking for this bird: an afternoon at all the best spots in Fairfield and a morning hitting the best locations on Cape Cod, from Eastham to Brewster to Barnstable. Thanks to a report for Tina Green, I paid the $9 entry fee and went for what has been a fairly reliable bird at Sherwood Island State Park in Westport. At first, I didn’t catch any sign of the bird at its favored wet ditch on the east side of the park. But then the bird called, and I was eventually able to catch a glimpse. Relief. Not from suffering or trauma. But from embarrassment.

Every year, there seems to be one bird or another that lingers far too long on my “NE Year Birds Needed” list. In 2014, it was Peregrine Falcon. In 2015, Marsh Wren was the bugger. And this year it was that aforementioned Empidonax.

I remember spending the last few days of 2010 furiously searching for Fox Sparrow, to no avail. All of these birds have widespread distributions and are on the scale of reliability in our region. But when there are so many to seek out annually, one or two inevitably slip through the cracks. For instance, I never made it to New York in time for the Kentucky Warblers at Doodletown (they stayed a lot later last year). Unlike the species mentioned above, this species is uncommon and rather restricted in our region, but not a species I wanted to miss (and at this point in the year, I’ve relegated it to the “Only by the grace of god” bin).

This is the stuff that fills the mind of a year lister. Year listing, for me (and many others), is mostly personal. I wasn’t worried about missing Willow Flycatcher because of what others might think. Birding always has been a very personal passion, and I was thus worried about missing the bird because I knew it would eat away at me.

Luckily, this seemingly easy species being outstanding for too long thing only seems to happen with one or two birds each year, and there are none I’m missing that currently fit that bill (at least for CT). Mostly, I find year listing to be a fun game of strategy and love competing with my previous totals. I also see it as a motivator to getting out into the field slightly more often and encouragement to visit new places.

I have kept a thorough year list since 2010, but am unfortunately thinking this will be my last year of dedicated year listing for a while. I will be heading off to college at the start of September (more on that soon), and unlike in middle and high school, I won’t have the same kind of flexibility or control on weekends. Besides, I have enough to worry about in college that doesn’t entail whether or not Glaucous Gull or Purple Sandpiper are still missing for the year.

I am fascinated to see how my interest in birds and birding will evolve as I move into the college and then the adult stage of my life. Maybe the year listing will come back at some point. Or maybe I just won’t be able to resist and will start one up for 2017. Or perhaps I’ll move on to another passion within birding (I already have several).

If anything, this whole exercise makes me appreciate that individual elusive species more. As I was driving to Sherwood, I remembered how an old birding friend and I used to love the Empid plates in the Peterson Field Guide, all illustrated for habitat coupled with song descriptions. I remember we were together the day I saw my first Willow Flycatcher. It was late June in 2008, and we were visiting a spot we visited at least weekly during that wonderful year: Larsen Sanctuary in Fairfield. It was the spot of so many firsts, from Yellow-bellied Sapsucker to Northern Pintail to Brown Creeper, so it’s not surprising to have first picked up Willow there. The bird was along the gasline cut that runs through the southern half of the sanctuary. I can still picture it in my head. Perched on one of the gas posts, eyeing us quizzically.

-Alex

Rare Birds of North America by Steve Howell, Ian Lewington, and Will Russell

I have spent the last several months poring over the subject work. In short, it is an incredible resource on bird vagrancy in North America. The amount of work the authors and illustrator put in is simply staggering (yet in keeping with Steve Howell’s super-human drive).

This book has been out for almost four years, so rather than turn this piece into a full-fledged book review, I want to offer my thoughts (in no particular order).

  • Ian Lewington is a remarkably talented bird artist, which is evident just by taking a look at the book’s cover.
  • Before reading, I had always imagined the species accounts (which begin on page 44 and continue until the end of the book) to be the most interesting part, and the material that comes before something I had to slog through in order to reach them. I quickly realized that is not the case. The forty plus opening pages covering the definition of a rare bird; vagrancy and migration in birds; source of vagrant birds in North America; and bird topography, molt, and aging were perhaps the most enjoyable and rich of the book, providing a solid grounding in the information that was to follow.
  • In keeping with this, the repetition in some of the species accounts served to ‘drive home’ the topics and methods of vagrancy covered in the opening sections (since many species, especially adjoining ones in the book’s layout had similar methods and patterns of vagrancy, molt, and plumages).
  • My favorite part of the species accounts was the ‘Comments’ section, when the authors went into depth about the records of a species, and the mechanisms of that species’ vagrancy. If anything, I wish these sections were longer for some species, and especially would’ve liked further speculation on if (and thus where/when) a species could show up again (hypothetical though that is).
  • One critique I have carries over from other books written by Steve Howell: he contradicts himself. It is perhaps impossible not to with a head as chock-full of bird knowledge as his is, but even so, it can be incredibly frustrating when an authoritative voice attempts to instruct you in the inverse of what it said the page before. I have in my notes that the first paragraph on page 174 (part of the Wood Sandpiper account) ‘completely contradicts’ what was said ‘regarding Common Greenshank and Wood Sandpiper vs Spotted Redshank in the Common Greenshank account.’
  • Another issue I have with Steve Howell is that he creates his own taxonomy and splits and lumps species at will. As well-supported by recent findings some of these actions may be, he has no authority to make them. Furthermore, when writing a book regarding rare birds to North America, the authors might want to follow North American bird names and taxonomy, in other words, those prescribed by the AOU. It is ignorant and perhaps patronizing to slip into ‘Greater Golden Plover’ (for Eurasian Golden-Plover) and to call Far Eastern Curlew ‘Eastern Curlew’ in the title of its species account (with Far Eastern in parentheses). Furthermore, hyphens are omitted for things like “European Golden-Plover” and “Lesser Sand-Plover.” Transgressions like these are regular and easily findable for anyone doing a close read of the text.
  • Although individually possessing far more knowledge on bird vagrancy than I, I do disagree with the authors on their theories on which route a couple specific birds took to reach their destinations. The most notable to me was the Rhode Island Wood Sandpiper of 2012, probably because I was able to see that bird myself. The authors argued for an East Asian origin for the bird, which is entirely possible. But they failed to mention the sizable invasion of Northern Lapwings that occurred that fall, as well as the weather conditions over Greenland and the North Atlantic that many thought led to that invasion. It is my feeling that the Wood Sandpiper found in Rhode Island is thus perhaps derived from Europe or Eastern Siberia (a possibility that the authors do acknowledge).
  • But the authors had only so much space to work in without turning this book into one of encyclopedic length, which they did masterfully. I am thrilled to have read this book, from which I have learned a tremendous amount. It was perhaps the bird book I most anticipated prior to its release, and it definitely lived up to its billing, masterfully covering a topic that is the passion of birders around the world.

-Alex

The Variability of Spring Migration Timing

Having been following along with the way weather impacts the arrival of certain migrants for a number of years now, I want to take some time to compare the ways spring migration has progressed over the last seven years. For the sake of the amateur birders/nonbirders that follow this site, I will refrain from getting technical about weather. In the future, I hope to make another post on this subject using historical weather data, but for now I will stick with my broad qualitative observations.

2010 was really the first year that I fully grasped the fact that weather has a direct impact on the quantity and diversity of neotropical migrants seen on a given morning, thus making it a logical place to start. I was a very active birder in 2009 and before, and enjoyed warblers and others thoroughly, but don’t recall following the weather in order to ascertain the numbers of birds moving and to plan my outings.

Because 2010 was the first year I was doing this, it is the year I sometimes use to compare the others to. Back then, I was going through rigorous treatment (and even had a major surgery right in the heart of spring migration), so my birding outings were limited. What strikes me most about 2010 is that it was kind of ‘normal’ (obviously, this observation needs to be backed up with data, which I will hopefully be able to do soon). We had our first major push of birds in late April, with diversity peaking in the NYC region by the middle of May.

2011, by contrast, was marked by a surprisingly early and strong start (beginning in the second to last week of April), before giving way to unfavorable winds for the beginning of May. Things turned back around (as they always do) by the middle of the month, with Blackpoll Warblers descending on the Northeast en masse by around the 15th.

2012 was a lot like 2010. Migration progressed in a fairly even manner, with the first big days occurring during the first week of May. It was my most memorable year for observing spring migrants; I went birding after school virtually every day, and really got to appreciate the subtle (and not so subtle!) changes that occur daily during the height of spring migration.

2013 was at times frustrating. It got off to a strong start at the end of April (much like 2011), before giving way to almost a week of sustained easterly winds to start the month of May. That was followed by a nice rebound in warbler diversity, but for me, the birding didn’t approach that of 2012.

It think the result for 2014 is almost predictable now. It was a lot like 2012 and 2010 (at least for me). It was right there with 2012 as being a really fun year for enjoying spring migrants, capped off by a Fairfield Big Day that recorded 23 warbler species, including a Kentucky.

I recall 2015 as being possibly the worst of all these years. Which is funny, because just to our north, my friend Dave Hursh reported having the best spring migration experience of his life at Mount Auburn Cemetery in Cambridge, Massachusetts, recording 20+ warbler species daily for almost three weeks.

2016 has gotten off to a fascinating start. Birds began to trickle through the closed floodgate (as they always do) during the last ten days of April. Then came a horrible period of eight straight days of overcast rainy weather, with unfavorable winds unyielding. Finally, things changed on the night of Saturday the 7th, with a massive coastal fallout occurring in SW Connecticut the next morning, as some of the lingering rain collided with impatient migrants in the first big night of migration of the season. Reports came in of 20+ warbler species from Stratford, New Haven, and elsewhere, with birds often keeping close to the ground and being quite tame. At the moment, there is a Nashville Warbler loudly singing outside my window, with an American Redstart joining in from across the street. I look forward to following the continued progress of Spring Migration 2016, which will hopefully follow along with its even-numbered predecessors!

Note: these are simply my observations, and thus your experiences may have been completely different. Was 2012 a paltry year for you with 2013 breaking all records? If so, definitely share your experiences in the comments section below.

-Alex

Cape May Warbler

After a long spell of wind, rain, and unfavorable winds, the floodgates have finally opened across the Northeast. I’ve managed to run up a nice total of nineteen warbler species over the past two days of birding my town, highlighted by a stunning male Cape May Warbler found at the Birdcraft Sanctuary this morning by Judy Richardson.

The bird provided killer views as it foraged just above eye level in a flowering willow, albeit in the bright midday light.

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-Alex