ABA Blog

2013 AOU Check-list Committee Proposals - Part 3

They're coming fast now. Not much more than a week after the second batch of proposals drops comes the third. Thanks to Morgan Churchill for keeping on top of the AOU's actions and posting them on the ABA's Facebook Discussion Group.

The disclaimers that should be second nature by now apply once more. These are proposals on which the committee has yet to vote, or at least they have yet to make those decisions public. No decisions are official until they are published in The Auk, the journal of the American Ornithologists' Union, this July. The entire list of proposals is available on the AOU's website here (.pdf). We'll focus on those proposals that affect the ABA-Area and Hawaii, which happens to be all of them this time around.

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Return Hawaii Creeper Oreomystis mana to the genus Loxops

The genus Oreomystis currently consists of two species, the 'Akikiki and the Hawai'i Creeper, which were considered to be closely allied due to similarities in ecology, behavior, and tongue mophology. As it turns out, however, the nuclear DNA suggests that Hawai'i Creeper is actually much more closely related to the honeycreepers in the genus Loxops, which consists of the 'Akeke'e and the 'Akepa, and the similarities between it and the 'Akikiki are the result of convergent evolution. Crazy stuff. Though the proposal places Hawai'i Creeper within Loxops, it may be that the species will actually require its own monotypic genus. Per usual, more study is required.

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Split White-breasted Nuthatch Sitta carolinensis into 2, 3, or 4 species

White-breasted Nuthatch has long been on the list of next potential splits based on obvious differences in vocalizations and subtle but consistent differences in plumage and bill size among the various populations. Moreover, those populations shake out in ways similar to established splits like the Solitary Vireos (Blue-headed, Plumbeous, Cassin's) and the sapsuckers (Yellow-bellied, Red-naped, Red-breasted). Recent genetic work bears this out, with an additional fourth clade occupying the southern Rockies south into Mexico.

If we're going to see some sort of split here though, the question of how many species will be pared off of Sitta carolinensis is still wide open. A four species split seems least probable, but three species (which combines the northern Rockies nelsoni and the southern Rockies/Mexico lagunae) would correspond to the three known vocal groups. As work still needs to be done to determine the contact zones between the three western subspecies maybe a simple east/west division is the most likely outcome. Assuming, of course, this proposal passes muster with the majority of the committee.

"Eastern" White-breasted Nuthatch, photo by Mike Bergin/10,000 Birds

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Adopt new English names for Artemisiospiza belli and A. nevadensis

The presence of this item on the docket, coupled with the first sentence reading, "Now that we have voted to split Sage Sparrow into two species," would seem to strongly imply that the Sage Sparrow split mentioned in the first of these posts is a done deal. New splits usually mean both species get brand new names, but these sparrows are not technically "new" species as they were treated separately by the AOU back in 1931. As such, it has been suggested that the committee buck the trend of proposing two new names and retain the name "Sage Sparrow" to refer to the sageland specialist A. nevadensis. The other can be called "Bell's Sparrow", a name which has long been used to refer to the westernmost subspecies

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Change the linear sequence of families in the Charadriiformes

More rearrangement here, this time of the various families in Charadriiformes on which there has been a lot of recent genetic work. Among other things this proposal moves the stilts/avocets and oystercatchers ahead of the plovers and places the alcids right between the skuas and the gulls.

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Transfer Providence Petrel Pterodroma solandri from Appendix to main list

Transfer Fea’s Petrel Pterodroma feae from Appendix to main list

Add Double-toothed Kite Harpagus bidentatus to the U.S. List

Add Rosy-faced Lovebird Agapornis roseicollis to the main list

Transfer Nandayus nenday from Appendix to main list and change English name to Nanday Parakeet

Add Asian Rosy-Finch Leucosticte arctoa to the main list

The proposals above are consolidated as they are all essentially housekeeping that serves to bring the AOU check-list in line with various recent updates to the ABA checklist. Providence Petrel, Double-toothed Kite, and Asian Rosy-Finch are added based on naturally occurring vagrants in Alaska, Texas, and Alaska again, respectively. Fea's Petrel is finally freed from its slashed purgatory as the species is recorded annually in North American waters and has been determined to be distinguishable from Zino's Petrel in the field. The two species of parrots were recently added to the ABA checklist based on established populations in Arizona (Rosy-faced Lovebird) and Florida (Nanday Parakeet).

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Update the classification of siskins & goldfinches

Having not that long ago seen our goldfinches and siskins removed from the long-standing Carduelis genus into the old-but-new-again genus Spinus (which re-created the hilarious and fun to say Spinus pinus for Pine Siskin), it looks like they'll be on the move once again. Those South American finches who had retained the genus Carduelis are now being reorganized into a much larger trans-hemispheric goldfinch/siskin group and Sporagra is apparently the oldest available name. It may turn out, however, that the North American goldfinches (American, Lesser, Lawrence's) are distinct enough to get their own genus, which would likely be Astragalinus.

Both are a pale shade of Spinus in this birder's opinion, but we can't have it all.

The full list, including background information and recommendations, is available here (.pdf)

A Tower to Remember

You are forgiven if you can’t guess the purpose of the odd building in this photograph from 90 years ago. You are forgiven, as well, if the name of Althea R. Sherman does not ring an ornithological bell.

She is the woman at the center of the picture, who conceived and designed the building. Her sister, Amelia, is at right, and they are accompanied by a group of neighborhood children in the tiny hamlet of National, Iowa. The photo, probably taken in 1923, is used by permission of the Oberlin College Archives in Oberlin, Ohio, where Sherman studied and taught art for a number of years.

The structure is a fascinating piece of ornithological history that deserves more widespread attention than it has received. The 28-foot-tall, 9-foot-square wooden tower topped by an artificial chimney is ingeniously designed to observe nesting Chimney Swifts. Sherman and other observers climbed stairs winding up three stories through the tower to the chimney.

An extraordinary self-taught ornithologist, Sherman (1853–1943) had the tower constructed to her careful specifications in 1915 at her residence amid the vast farm country of northeastern Iowa. Remarkably, it still exists, and what an achievement it would be to restore it!

That is exactly the goal of a nonprofit organization, the Althea R. Sherman Project, which is campaigning for funds to make it possible. There are good historical and ornithological reasons for the restoration. As leaders of the project note on their website, the tower allowed Sherman to be “the first person ever to witness and record the entire nesting cycle of these birds. Her Chimney Swift journals, covering 18 years and more than 400 pages, may offer the most extensive study of this species in existence.”  

Reading some of Sherman’s minutely detailed day-by-day notes, you will see that the project leaders do not exaggerate. Excerpts from the journals are published as a chapter “The Home Life of the Chimney Swift” in her posthumously published 1952 book Birds of an Iowa Dooryard. A 1996 edition of the book includes a great deal of interesting background on Sherman and her various ornithological projects.

Dilapidated and in storage after many decades of disuse, the rehabilitated tower will be moved to the Cedar County Historical Society’s Bickett-Rate Memorial Preserve near Buchanan, Iowa. The preserve includes a bird sanctuary, a museum, and an environmental education center.

You will not need to go to Buchanan to see the nesting show. The stairs inside will not accommodate visitors, but it will eventually include two webcams and a microphone. If swifts decide to use the beckoning “chimney,” you’ll be able to peep at their domestic life via the Internet. Robert Anderson, executive director of the Raptor Research Project, is donating the webcams.

How soon the restoration will be completed depends on success of the fund-raising campaign. The tower is certified as eligible for status in the National Register of Historic Places, and the State Historical Society of Iowa has awarded the project a matching grant. Now the project leaders are seeking the $87,000 necessary to receive the other half of the grant.

Besides its historical, ornithological, and educational values, the tower will have a third important benefit: conservation. It will call attention to the dire plight of the Chimney Swift, whose relative abundance in the U.S. and Canada has declined 66% from 1966 to 2011, according to the North American Breeding Bird Survey.

That is almost exactly the decline reported for Iowa, which is severe enough to warrant conservation attention there. The plunges in relative abundance are even more severe in southeastern Canada and the northeastern U.S. For example, during the same 1966–2011 period, the survey shows declines of 97% in Nova Scotia and Ontario, and 90% in Maine. Clearly, the Chimney Swift needs all the conservation attention it can get.

An article in my News and Notes column in Birding (July 2011, p. 27) described a combination of dangers contributing to the Chimney Swift’s decline. First is a decrease in acceptable breeding sites as suitable chimneys have dwindled in residential and other architectural designs. Another is a decline in the abundance of flying insects, perhaps because of increased use of pesticides. A third may involve ecological threats in the species’ South American winter range that are not well understood.

It’s worth noting that ABA’s Bird of the Year, the Common Nighthawk, faces the exact same trio of troubles: dwindling nest sites, food shortages, and threats in its South American range. A recent News and Notes article (Birding, March–April 2013, pp. 26–27) reported the nighthawk’s decline, and a feature article in the May/June 2013 Birding will explore the matter in greater detail.

As for the Chimney Swift, there is scarcely a better examination of its breeding behavior than Althea Sherman’s tower and her nearly two decades of observations. One of her comments in Birds of an Iowa Dooryard sounds quaint today, but it represents the feelings she had for the bird:

“During the many summers of intimate living with the Chimney Swift, I have never found it a subject for criticism in any respect—no evil has been detected in its relations with its own or with other species. In short, it appears to be a paragon of perfection—the bird that properly might be chosen as the emblem of peace.”

Yes, quaint, reflecting an almost spiritual relationship between the lady and the bird, but let us not be cynical about the role such statements had in ornithological writing a century ago. They were altogether typical of her time. After all, “modern” bird lovers have a similar feeling about our favorite species, even though we don’t express it in such an old-fashioned way.

The Althea R. Sherman Project is doing its part to help resurrect such personal respect for the Chimney Swift and, in the process, for all of nature. That’s an eminently worthwhile environmental goal.

 

Here We Go Again

The American Ornithologists’ Union’s Committee on Classification and Nomenclature of North and Middle American Birds—the AOU Check-list Committee, for short—sure has been busy of late. Splits (lots) and lumps (not so many), especially those affecting North America north of the U.S.–Mexico border, inevitably elicit the loudest response from birders. But maybe the most substantial changes are the big checklist shuffles, dramatically affecting the linear sequence of bird names across large swaths of the Check-list.

In recent years, the Check-list Committee has massively reorganized such speciose and familiar groups as the gulls, terns, and warblers. Remember all those Larus gulls? Many of them have new scientific names, and new positions on the Check-list. How about the Sterna terns? They were even more drastically overhauled. And, of course, the Dendroica warblers. Birders took that one especially hard, it seems to me. There’s just something really weird, I guess, about seeing the familiar ole Black-throated Green Warbler practically at the bottom of the warblers, with a new name (Setophaga), no less—way, waaay further down the checklist than the Ovenbird, the Northern Waterthrush, and the Connecticut Warbler.

What’s next?

How about a major reorganization of the large sandpiper family, so well represented here in North America.

 

The AOU has already made inroads here. The genus Tringa (the “shanks”) was recently reorganized, with such surprising results as the placement of the distinctive Willet not only within the shanks, but, in fact, between the Greater and Lesser yellowlegs.

Now, Paul Hess reports in the March/April 2013 Birding (“Sorting Out the Shorebirds,” pp. 27–28), a considerably larger overhaul may be in the works. Check out the figure at right, a distillation of a major new analysis by Rosemary Gibson and Allan Baker. In the Gibson–Baker scheme, the phalaropes would be united with the shanks. The godwits and curlews—which I’d always thought of as pretty close—would be quite far apart. Think about it: The Marbled Godwit, in this configuration, is closer to the Ruff and the Broad-billed Sandpiper than it is to the Long-billed Curlew.

Speaking of Ruffs and Broad-billed Sandpipers, the new research—reported by Gibson and Baker in Molecular Genetics and Evolution 64:66–72—proposes genus-level changes that will surprise almost all of us. Check this out: The Ruff, Broad-billed Sandpiper, and Sharp-tailed Sandpiper are closely related to each other, according to the new research. What about the Sharp-tail’s kissing cousin, the Pectoral Sandpiper? In the new arrangement, the Pec goes with Western Sandpiper, Semipalmated Sandpiper, and—wait for it—Buff-breasted Sandpiper.

 

I could go on, but you get the point. If the Gibson–Baker findings are evaluated and accepted by the AOU, our checklists will look very, very different. Which brings me to a question:

Do you like all these changes?

I confess, and I think many of you already know: I love these checklist changes! For me, it’s exhilarating to be a birder in an era of such rapidly evolving knowledge and understanding. At some point in the next few weeks, I’ll be seeing Greater and Lesser yellowlegs, Wilson’s Phalaropes, Willets, Marbled Godwits, and Semipalmated Sandpipers. And I’ll look at them with eyes wide open, wondering anew about their similarities and differences, their behavior and ecology, their vocalizations and plumages.

Offshore, I’ll see some ducks—they’re related to turkeys and chachalacas. A grebe will swim by—apparently, it’s allied with the flamingos. Then, if I’m lucky, a Peregrine Falcon will put up the shorebirds. And check this out: That Peregrine is more closely related to the pipits and swallows along the shore than it is to the Red-tailed Hawk sitting in the tree a bit farther out.

“There is grandeur in this view of life,” Charles Darwin wrote, in the finale to his Origin of Species, “...that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.”

There is grandeur, too, in the view that human learning and understanding are forever advancing. Wouldn’t it be boring if the state of our knowledge suddenly froze in place? Wouldn’t it be disappointing if our checklists suddenly stabilized, never to change again?

 

 

Open Mic: Never Mind the Bullock's - Taking Molecular Studies with a Grain of Salt

At the Mic: Steve N.G. Howell

Steve is a senior international bird tour leader for WINGS and has written several books including A Guide to the Birds of Mexico and Northern Central America, Gulls of the Americas (with Jon Dunn), and most recently, Petrels, Shearwaters, and Albatrosses of North America.  He lives near Point Reyes, California.

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There's no denying it: Molecular studies are helping us unravel the mysteries of avian relationships, and quickly. But until we fully understand the finer principles of genetics, the history of genes, and what that all entails, we will continue to make mistakes in our interpretations of the results of molecular studies. Is there anything we can do about this? Perhaps we can start with a grain of salt, and if that doesn't work then it's time to break out the lime and tequila.

A Tale of Two Orioles 

As an example of the tribulations involved in molecular studies, let's review some recent developments with a time-honored favorite in the North American taxonomic arena - the Northern Oriole complex. The taxonomic tale of Baltimore Oriole Icterus galbula and Bullock's Oriole I. bullocki is fairly well known - two species, then one, and now three (what, three?). Less well known to most ABA members, perhaps, is the Mexican cousin of Baltimore and Bullock's - Abeille's Oriole I. abeillei (unhelpfully named Black-backed Oriole by those seemingly unaware that 12 of 16 oriole species in Mexico have black backs, including both Baltimore and Bullock's).

            In 1999, a molecular phylogeny of New World orioles was produced, in which, supposedly, Baltimore Oriole and Abeille's Oriole were closely related, while Bullock's Oriole was more closely related to Streak-backed Oriole I. pustulatus (Omland et al. 1999, Molecular Phylogenetics and Evolution 12:224-239).

            The authors realized how odd this looked, so a fuller genetic analysis was undertaken, which confirmed the earlier result (Kondo et al. 2004, Condor 106:674-680); it was then postulated that this was an amazing example of adult male plumage patterns diverging very quickly in an evolutionary time scale (between Baltimore and Abeille's). A follow-up paper by the same team (Kondo et al. 2008, Evolution 62-5:1182-1191) went on to show that Abeille's Oriole was derived from Baltimore Oriole (Bullock's Oriole was ignored). This was thus a remarkable case of a tropical resident species evolving from a migratory ancestor, contrary to the paradigm of resident tropical avifaunas tending to be the reservoir from which migration flows. Another paper used the new and "robust phylogeny" to explore the evolutionary history of plumage patterns in orioles (Omland & Lanyon 2000, Evolution 54:2119-2133). Another paper using the new phylogeny postulated that orioles colonized mainland South America from Caribbean islands (Sturge et al. 2009, Condor 111:575-579). And so on.

The adult male of Abeille's (or Black-backed) Oriole (shown here) is a striking bird, although the female looks very similar to Bullock's Oriole and the two species can be difficult to separate in female/immature plumage. Ciudad Guzmán, Jalisco, Mexico, March 2012. © Steve N. G. Howell.

            Amazing stuff. But this is where the trail of genetic clues led, so how could it not be true? Hence, the AOU (2000, Auk 117:847-858) moved Bullock's Oriole to follow Streak-backed Oriole, and thus separated it from Baltimore Oriole by five other species. Whiskey Tango Foxtrot was the response of many field ornithologists, but what did they know of genetics?

            However, as knowledge of genetics increased, further molecular analyses of these orioles showed that the earlier grouping of Baltimore and Abeille's was in error (Jacobsen et al. 2010, Molecular Phylogenetics and Evolution 56:419-427; Jacobsen & Omland 2010, Ecology & Evolution 2:2413-2429). Today it is believed that Abeille's is more closely related to Bullock's Oriole, which fits with older conclusions based on morphology, vocalizations, and biogeography. These two orioles are a good example of how messy the progress has been in applying new genetic tools to avian taxonomy, for only a few years ago these two were "among the most closely related of avian species" (Kondo et al. 2008:1183).

            Along with a clearer understanding of "Northern Oriole" relationships, the claims of rapid plumage evolution and of a resident tropical species deriving from a northern migrant are also now debunked. And given that the baseline phylogeny was flawed to an unknown degree, is it still true (as claimed by Omland & Lanyon 2000:2119) that "plumage patterns and colors are highly labile between species of orioles?"  

            Still, after a litany of at least five publications it would appear that we have established something more firmly than before, and hopefully we have a better understanding of the evolutionary history of these three species. But these three species of orioles live in North America, where many people were familiar enough with the birds to notice that the genetic results were incongruous with intuition. For the other species, less familiar to most people, the original results of Omland et al. (1999) appear not to have been questioned. My opinion is that most of their results look reasonable, yet it is entirely possible that some of the other relationships "proven" by genetics and statistics are in error. For example, Orange Oriole I. auratus and Streak-backed Oriole might be closer than reported. Either way, the unfortunate error involving Baltimore Oriole and friends does not instill confidence. Moreover, some well-marked, potentially species-level taxa were omitted from the analysis, despite "the importance of dense taxon sampling" in the title of Omland et al. (1999); an example would be Dickey's Oriole I. [graduacauda] dickeyae of west Mexico.

            These molecular studies on relatively well-sampled orioles exemplify how little scientists really understand/understood about genetics. And these flaws went on to color or discolor a number of ecological and environmental studies and theories. Some might cry: "But that was then, this is now; today we really do understand things." Certainly one would like to think that our knowledge of genetics has improved in the past few years, but how much?

 

What Do We Not Know?

Although some may claim otherwise, avian geneticists are still groping around in a recently tilled but dimly lit field, learning how to use their new tools. Thus it seems only common sense to treat their early harvests as working hypotheses, especially at the taxonomic levels of genus and species. This is particularly true given that ornithologists can't even agree on what constitutes a species. In this regard, check out the eloquent but sobering essay entitled "A species is whatever I say it is" by Nigel Collar in the March 2013 issue of British Birds (vol. 106:130-142), which highlights numerous other examples of the unresolved issues with genetic studies.

            Although problems with genetic analyses may be fewer than those associated with studies based on non-genetic data, they are still problems. Despite this, taxonomic committees appear to have fallen in love with "glamorous" DNA studies, seduced by the promise of ultimate truth. Hence it often seems they are running amok on freshly plowed soil of uncertain viscosity, undervaluing or ignoring non-genetic tools that might help them avoid getting needlessly stuck. One day, who knows, the genetic tools may be so refined that we won't need any other lines of evidence, but there will be years or decades of messiness before we reach that point - if we ever do.

            In the meantime, species and genera are constantly being shifted around hither and thither. Bullock's Oriole is only the tip of the iceberg. Of course, birders only "suffer" from all this if they try to keep up with lists that are changing every week, or with using field guides compelled to adopt the latest and greatest changes - regardless of whether these changes are helpful for somebody trying to identify a bird. I can only think that poor Roger Tory Peterson must be rolling in his grave, now that the new Peterson field guides to birds try to follow taxonomic sequence - which is contrary to the simple brilliance of Peterson's original system.

            One cannot help but wonder how many more taxonomic decisions fueled or driven solely by genetics are simply errors in analyses. The merger of skuas into the genus Stercorarius, because Pomarine Jaeger is supposedly more closely related to Great Skua than to the other jaegers? Putting Willet in between Lesser Yellowlegs and Greater Yellowlegs? Are all the recent wood-warbler genus reshuffles truly accurate, or might some be changed again? And how about them sparrows and towhees? And so on... How many things do we not know that we don't know?       

Thanks to Ned Brinkley, Burr Heneman, Alvaro Jaramillo, Peter Pyle, and Brian Sullivan for comments on an earlier version of this essay.

P.S. As of March 2013, the AOU check-list still separates Bullock's Oriole from Baltimore Oriole by 5 species of orioles: Orange, Jamaican I. leucopteryx, Spot-breasted I. pectoralis, Altamira I. gularis, and Audubon's I. graduacauda. Yet Yellow-backed Oriole I. chrysater is 9 species distant from Audubon's, despite the phylogeny of Omland et al. (1999), which placed Yellow-backed and Audubon's as each other's closest relatives (a view that is supported by morphology, voice, and biogeography, pending analysis of the unsampled taxon dickeyae, mentioned earlier). Time to pass the tequila...

 

Pennsylvania: The Second Snapshot

A review by Troy Corman

Second Atlas of Breeding Birds in Pennsylvania, edited by Andrew M. Wilson, Daniel W. Brauning, and Robert S. Mulvihill

Penn State University Press, 2012

586 pages, $64.95—hardcover

ABA Sales / Buteo Books 13906

I was raised in rural south-central Pennsylvania, but moved away before fieldwork began in 1983 for the state’s first breeding bird atlas. Fortunately, though, projects like this are designed to be repeated, and when data collection for the second atlas started, twenty years later, I was able to spend a week or so of several consecutive Junes in the same forests and along the same streams and trails where my passion for the outdoors and birding had first taken flight, a passion that has guided my career path ever since.

Pennsylvania may not be a major U.S. birding destination, but its varied landscapes attract a remarkable selection of both resident and migratory breeding birds—at least 208 native and established exotic species are confirmed to have bred there, among them an amazing 30 species of warblers. That rich species diversity and the commonwealth’s long and impressive history of ornithological investigation is the subject of several books, including the first Atlas of Breeding Birds in Pennsylvania, published in 1992.

As dedicated atlasers already know, the production of a breeding bird atlas requires monumental effort on the part of hundreds, if not thousands, of skilled volunteer birders and professional ornithologists. And it all has to be repeated. As the North American Ornithological Atlas Committee notes, “The tremendous value of breeding bird atlases will only begin to be realized when each state or province completes their second atlas. At that time, two ‘snapshots’ in time of breeding bird distributions will be available for comparison and conclusions can be reached about the changes in distributions that have occurred.” Repeated atlasing, of course, also provides data on population trends, which can prompt research and conservation efforts for declining species and the habitats on which they depend.

Data for Pennsylvania’s second atlas were collected from 2004 to 2009, and the new book that resulted from that work provides us with an up-to-date overview of the current distribution and status of each breeding species, plus a tremendous amount of insightful analysis.

Early chapters in the Second Atlas discuss the goals and purpose of the project. The project framework and survey methods remained largely the same from the first to the second atlas, though there were efforts made to capture certain aspects missing from the first: For example, field crews were hired this time around to take point counts measuring the geographic variability of species abundance. One of my favorite sections in the new Atlas is the enlightening chapters describing the state’s geography, habitat, and land use. The many color maps and vivid descriptions provide a thorough introduction to the physical aspects of Pennsylvania’s environment that influence the distribution and abundance of the avian life that breeds there. 

Another brief chapter, “Interpreting Species Accounts,” greatly increases the reader’s appreciation of the many fine details to be gleaned from each of the 190 two-page accounts, prepared by no fewer than 52 authors. Those authors and the book’s editors—Andrew M. Wilson, Daniel W. Brauning, and Robert S. Mulvihill—have taken full advantage of technologies and analytical methods that have emerged since publication of the first Atlas, making this second a sharply attractive, revealing, and masterfully prepared book.

Each species account includes a very good to excellent color photo, often, aptly, depicting adults at the nest or engaged in other breeding behavior. As expected, comparison of the data collected for each of the atlases is a significant part of these accounts; distribution changes (or their absence) are noted, and the Pennsylvania information is often compared with that discovered by second atlasing efforts in some adjacent states and provinces, thus placing apparent trends into a regional context.

Understandably, there is an obvious effort to avoid duplicating information already captured in the first Atlas. However, I find it mildly disappointing that so much natural history information has been omitted from the new species accounts. Appendix F in the Second Atlas provides a tabular summary of phenological data for most species; I would have liked to see some explicit discussion of the differences in breeding phenology discovered between the two atlases. Data continues to accumulate suggesting that the average timing of some species’ migration and nesting has already begun to shift, shifts possibly related to climate change.     

The second page of each account features two or three easily interpreted statewide maps. The first and largest depicts where the species was detected during the second atlas. Any changes in distribution between the two atlases are clearly noted on the second map. In the case of more common and widespread species, a third map depicts the geographic density of singing males as determined by point counts.

Each account also includes a table showing the number of blocks in which the species was identified by each atlasing project as a possible, a probable, or a confirmed breeder; changes between the two atlases are expressed as a percentage. Worrisome numbers include those for the Red-headed Woodpecker, which declined by 46 percent, and for the Golden-winged Warbler, down 61 percent between the two atlases. Compare that with the incredible increases in breeding Common Ravens—114 percent—and Bald Eagles—949 percent! These changes are discussed in detail in each account, with insightful suggestions as to why specific species have declined or increased, or why their distribution in the state has shifted.        

Appendix A includes brief accounts for a dozen former nesting species and a table listing ten additional birds that have not been documented nesting in Pennsylvania since the 1970s or before, including the Heath Hen and the Passenger Pigeon. Oddly missing from this list is the Glossy Ibis, noted in the first Atlas as a confirmed breeder on the Susquehanna River in the 1970s.

Few other resources provide so complete a picture of bird distribution over time as a breeding bird atlas, and few are so helpful in the long-term monitoring of avian populations. It is hard to imagine that any birder would not want a copy of the Second Atlas, whether in Pennsylvania or anywhere in the region, a region that stretches as far north as Quebec and as far west as Ontario (both jurisdictions, by the way, with magnificent atlas projects of their own). An exceptional summary of a large amount of data, presented in a sharp and impressive tome, this work sets a new standard for atlases to come.

It may take up a lot of space on your bookshelf, but as an informative and inspiring reference, the Second Atlas of Breeding in Birds in Pennsylvania is a worthy tenant. I am honored to be one of the many who participated in this endeavor. As much as I learned while helping collect data, I continued to be enlightened as I reviewed this fine resource.

Troy Corman is a biologist in the Arizona Game and Fish Department, where he coordinates long-term statewide bird monitoring projects. He coordinated the Arizona breeding bird atlas project and served as co-editor of the Arizona Breeding Bird Atlas (2005). Corman is president and a founding member of the Arizona Field Ornithologists. His interests include the distribution and seasonal status of birds, conservation, and travel.

Recommended citation:

Corman, T. 2013. Pennsylvania: The Second Snapshot [a review of Second Atlas of Breeding Birds in Pennsylvania, edited by Andrew M. Wilson, Daniel W. Brauning, and Robert S. Mulvhill]. Birding 45(3):67.

What Lies Beneath?

A review by Donna Schulman

 

The Unfeathered Bird

by Katrina van Grouw

Princeton University Press, 2013

304 pages, $49.95—hardcover

ABA Sales / Buteo Books 13698

Remember those crinkly transparent overlays in the anatomy articles of your childhood encyclopedia? The blood vessels, then the muscles, then the organs. Or maybe it was the other way around. Eventually came the bones, and that was the best part, because bones were supposed to be scary—but those diagrams were strangely beautiful.

I felt the same combination of wonder and mystery when I examined the illustrations in The Unfeathered Bird, a unique book on anatomy and art and birds. As an art student in Great Britain twenty-five years ago, Katrina van Grouw conceived the mission of creating a volume that would combine the authority of an ornithological text with the visual beauty of nineteenth-century scientific illustration. The result is a large and elegant book, well designed and well produced, printed on thick cream-colored paper and composed in typefaces that echo those of pre-industrial times. At the heart of The Unfeathered Bird are the book’s more than 300 drawings: They are simply beautiful, in spite of the fact—because of the fact—that they depict bones and muscles.

The book is divided into two parts. The first, “Generic,” presents the blueprint for avian flight. Here we learn the basics of bird anatomy, especially the adaptations—a rigid trunk, a lightweight skeleton, and a flexible neck—that enable a bird to fly. The second, much longer part, “Specific,” comprises forty-one chapters devoted to taxonomic groups, mostly orders and families, and focuses on the anatomical variations, some familiar, some bizarre, that have evolved over the ages.

These “specific” chapters are grouped into six sections, corresponding to the Linnaean orders Accipitres, Picae, Anseres, Grallae, Gallinae, and Passeres. Van Grouw’s use of an eighteenth-century taxonomy “concerned only with outward structural appearances” allows her to indulge her fascination with convergent evolution, the process by which creatures that are only remotely related develop the same traits independently. For example, cranes, storks, and herons, neatly separated in modern classifications, have all developed long legs and long necks; hornbills and toucans, groups only distantly related to one other, have evolved huge bills. The Linnaean sequence lets van Grouw and her readers examine such similarities in appearance and adaptation unencumbered by the niceties of modern taxonomy. Not, of course, that van Grouw is anything less than familiar herself with the latest research, as her discussions in the text reveal; but it seems to me that she also feels an affinity for the older system, as concrete and solid as the bones she has embraced.

There is a lot going on under a bird’s skin, and van Grouw draws back the feathered veil layer by layer, showing birds with their skin removed, birds reduced to skeletons, bird skulls furnished with bills large and small, and bird feet with and without their scaly skin. Sepia-toned, cross-hatched, and finely detailed, her Mallards, Gentoo Penguins, and Great Spotted Woodpeckers, to name a few, do indeed have a nineteenth-century quality. (In an interview, van Grouw cites among her inspirations Thomas Eyton’s 1867 Osteologia Avium.) Pencil is used to delineate the edge and curve of bone, shadowing gives the muscles and feet substance, and a slight tilt of the skull makes the skeletons seem almost alive. The unclothed birds fly and swim and prance across the pages, much in the manner of the dead birds John James Audubon posed for his paintings. And like Audubon’s paintings, these illustrations embody a strong sense of design. The Northern Lapwing raises the bones that are its wings in sweeping diagonals; the skeleton of the Great Hornbill zigzags up from its perch, its great crescent bill stretching across the corner of the page.

The book is also full of drawings of parts of birds, mostly skulls and feet but also breastbones, wings, windpipes, and tongues. Skulls and feet are often shown in groups, revealing their striking range of sizes and shapes. It’s amazing how much easier it is to see the differences among the Darwin’s finches when you take away the feathers!

Similarly, drawings of one species in different stages of “undress,” such as this Barn Owl—its feathers, skin, and muscles removed one after the other to reveal the structure of its ear flap—function as visual lectures in ornithological biology.

Unexpectedly, domestic birds—waterfowl, fowl, and pigeons—are also unfeathered here. It turns out that the history of selective breeding over the centuries reveals a great deal about anatomical possibilities and limits. The description and drawing of the skull of the crested duck, an ornamental Mallard with a pouf on the top of its head, is heartbreaking: This bird has been bred for a genetic defect, a hole in its skull, which makes it look cute but often results in the growth of bone tendrils into the brain.

Rock Pigeons have also been bred into bizarre-looking types. This bird that so many birders love to hate is lavishly illustrated in a number of its most extreme domestic manifestations, including the African Owl, with its extremely small bill, and the Fantail, with its concave back. Van Grouw reminds us that Charles Darwin bred pigeons, the fancier the better, and found in them eloquent examples of mutability.

There is a surprising amount of text in The Unfeathered Bird, and it is worth the reading. Thanks to a background in taxidermy and seven years spent as curator of the ornithological collections at London’s Natural History Museum, Katrina van Grouw is conversant with what seems like every single bone in every single bird species, and she exhibits a notable talent for graceful explanations uncluttered by scientific jargon.

Here she is on the woodpecker’s tail:

Now a tail is not just a convenient bundle of feathers to lean on. It takes muscle power to function effectively as a brace, and large muscles need large bony surfaces to anchor to. The tail vertebrae of a woodpecker do not diminish in size toward the tip, and the final bone—called the pygostyle—is enormous, with a broad flattened underside for the muscles to really pull those tail feathers against the tree.

With the same appealing clarity, she explains why Anhingas have an extra bone in their neck, how hummingbirds’ wings are attached to their bodies by a ball and socket joint that allows them to fly like helicopters, and what nightjars have—a tapetum lucidum—that owls don’t that allows them to truly see in the dark.

The highly detailed descriptions of bones and eyelids and toe pads and mandibles never get boring, because all of those details are ultimately related to bird behavior. Toucans are able to nest in cramped tree cavities because their tails flip forward. Storm-petrels’ well-developed sense of smell allows them to return to their breeding sites at night. The occasionally overwhelming density of the materials would make this a hard book to read in one sitting, but it is a delightful one to read in pieces, a chapter or two a day.

It is hard to peruse The Unfeathered Bird without wondering about the story behind the book. Van Grouw made every drawing life-size on oversized paper from a specimen—all borrowed from museums or found already dead; no birds were harmed in the making of this book. As the author has related in interviews and on the book’s website, freshly salvaged carcasses were boiled and cleaned in van Grouw’s house by her husband, Hein van Grouw, who also wired the skeletons into lifelike poses; the couple’s joint endeavors apparently gave their home a very distinctive look. In the acknowledgments, the author thanks people around the world for gifts of carcasses and alludes to what must have been a memorable meal of bustard soup: I wish that she had recounted more such episodes in the book’s introduction, where they would have provided an engaging and illuminating context for the book's drawings.

My other quibble with this book is the index, which covers only the illustrations, a matter that is not explained. Both English names and scientific names are indexed, with English names entered under their first word, for example, “Parakeet Auklet” rather than “Auklet, Parakeet.” This means you need to know exactly which bird you are trying to look up, and its precise, full, and correct name. There is no bibliography or list of recommended sources, a source of regret for the reader: I like seeing where people get their expertise and inspiration. I did enjoy the Mallard skeletons that frame the index, as well as the European Robin skeleton at the end of the book, flat on its back, legs in the air, clearly dead. After so many skeletons in action, this was a fun touch.

I saw an errant rooster this morning at my favorite birding patch. Instead of walking past, I watched it. I thought about its stationary eyes and flexible neck, its footpads and its four toes, three in the front, one in back, all reasons why it was walking so daintily over the graveled parking lot with its head bobbing. This is what I got from The Unfeathered Bird, a new way of looking at birds, even the most common ones. An anatomical point of view gives us a deeper understanding of the behavior we observe in the field; it adds to the information in our field guides and handbooks. The Unfeathered Bird is not a reference book, nor is it entirely an art book, despite its exquisite drawings. Its failure to fit completely into a genre niche is its strength, making this a unique volume that beautifully presents difficult information in a manner that is easy to understand. While not a necessary purchase, it is a book that I think will add value to the birder’s library.

What lies beneath? In the case of The Unfeathered Bird, a world of skeletal pleasure.

 

- Donna Schulman is an academic librarian and birder. The author of more than 120 book reviews, she is the Book Review writer at 10,000 Birds. Schulman birds in New Jersey and, across two rivers, in Queens, New York, where she is preparing for this November’s New York Birders Conference and annual meeting of the New York State Ornithological Association.

 

Recommended citation:

Schulman, D. 2013. What Lies Beneath? [a review of The Unfeathered Bird, by Katrina van Grouw]. Birding 45(3):65.

2013 AOU Check-list Committee Proposals

It's split and lump season already, and the proposals for the most recent taxonomic updates to the AOU North American Check-list, which in turn are incorporated into the ABA Checklist, have been kicking around on the internet for a few weeks now. The AOU is considering 13 proposals that have been submitted in 2012, not all of which involve ABA-Area birds as the AOU's North American jurisdiction includes Mexico and Central America to Panama's southern border.

It's important to note that these are proposals on which the committee has yet to vote, or at least they have yet to make those decisions public, and as always there are some that are unlikely to make the cut formally but are still interesting from a systemics perspective. This post will only mention those changes that affect the ABA-Area, but if you're interested please refer to the official list of proposals for the whole ball of wax (.pdf).

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Recognize Cabot’s Tern Thalasseus acuflavidus as distinct from Sandwich Tern T. sandvicensis

One of those Old World/New World splits that is not entirely unanticipated, a proposal was made to formally split the North American acuflavidus ssp and South American eurygnathus ssp of Sandwich Tern from the nominate Eurasian sandvicensis. The proposal is based on differences in mtDNA which found the New World populations to be closer to Elegant Tern. The New World birds would then be called Cabot's Tern.

While there are currently no confirmed records of nominate Sandwich Tern in the ABA-Area (an oversight birders in the northeast US and the Atlantic provinces will probably go about remedying in short order), an unusual Sandwich Tern in Illinois in 2010 was as good a candidate as we've ever seen and undoubtedly deserves closer scrutiny in light of this proposal. More information on that bird is available at the North American Birding blog.

North America's first nominate Sandwich Tern? photo by Rick Remington, Chicago, IL, September 2010

 

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Split Barolo Shearwater Puffinus baroli

Splits among the tubenoses have become de rigueur as we learn more about how they segregate themselves on and among the archipelagos where they breed, and the small Puffinus species have been a particularly tough nut to crack. Barolo Shearwater is split from Little Shearwater by voice, morphometrics, and, of course, mtDNA. This affects the ABA-Area as all North American records of Little Shearwater have been identified as this subspecies, which would then replace Little Shearwater on the ABA Checklist. 

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Revise the classification of sandpipers and turnstones

We've become more or less accustomed to the rearrangement of one or more groups of birds every year. This time the genera Arenaria (turnstones) and Calidris draw the short straw. 

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Split Sage Sparrow (Artemisiospiza belli) into two species

This is a cool one that would add a new species to the ABA Checklist. We've known for some time that the two populations of Sage Sparrow, nevadensis of the Great Basin and belli of California, differ from each other in significant ways and do not interbreed in areas where both are found. They've even been treated as separate species by some authorities, notably sparrow guru James Rising.

The mtDNA of thr two populations looks to confirm what was always suspected, and the two groups differ significantly genetically in addition to the long observed differences in appearance and song for what seems to be a pretty clear cut split. The only question now is what to call the new species. Great Basin Sparrow and California Sparrow? Or will we pull out the dreaded hypens for our two Sage-Sparrows?

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Change the generic placement of Otus flammeolus

Turns out our little dark-eyed, migratory, moth-eating Flammulated Owl is not as closely related to the Old World Otus owls as previously suspected, but it's not really like the New World Megascops Screech-Owls either. The best option then is to defer to noted golden-age ornithologist Elliot Coues, who placed them in their own Psiloscops genus way back in 1899. Everything old is new again. 

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Recognize Hanson’s new species of White-cheeked Geese, Branta spp.

Undoubtedly the proposal most likely to cause North American birders to tear out their own hair is the one that makes the case for paring off an additional four species from the Canada Goose complex. The proposal is based on a posthumously published work by ornithologist Harold Hanson and, given the fact that Hanson meticulously described over 200 distinct subspecies of Canada and Cackling Goose, perhaps we should be thankful that only four made the cut.

Richard Banks, who reviewed Hanson's magnum opus in the Wilson Journal of Ornithology, urges caution. For that reason and other, perhaps obvious, ones it's a very unlikely proposal to pass. I don't know about you all, but I'm pretty relieved about that.

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Move the Hawaiian honeycreepers (Drepanidinae) to subfamily Carduelinae

Not in the ABA-Area (at least, not yet), Hawaii's honeycreepers have been shuffled around the passerines for decades and most recently were slotted into Fringillidae. This most recent analysis of the family's genetics puts them into subfamily Carduelinae, with Pine Grosbeak and the Carpodacus rosefinches of Asia as sister taxa.

Swallows Evolve to Better Avoid Traffic?

 

Cliff Swallow, photo from wikipedia

Any birder who has driven over a bridge almost anywhere in North America has undoubtedly noticed that Cliff Swallows have readily taken to those man-made structures as nesting sites.  But a study, recently published in the journal Current Biology, of Cliff Swallows in Nebraska has shown that the act of choosing these sites over the last 30 years is selecting for traits that better allow the birds to avoid the traffic which is an occupational hazard of nesting so close to roads. 

 

The researchers, Charles Brown and Mary Bomberger Brown of the University of Tulsa and the University of Nebraska respectively, first noticed something interesting was going on when they realized that the frequency of road-killed swallows over the 30 year time frame had declined rather dramatically while the population of birds nesting under the bridges, and the traffic on the road, had increased. If natural selection favors those birds that learn to avoid cars that might be expected, but the researchers noted, through thirty years of banding nesting swallows and salvaging road-killed birds, that wing length in the birds killed by cars was significantly longer than the population at large.

They concluded that those birds with shorter wings were more maneuverable, particularly when taking off from the road ahead of approaching cars, and that the passage of cars on the road was selecting against those birds with longer wings.

From a Scientific American article on the results:

[Charles] Brown says that there is evidence that shorter wings make the animals more agile: “they can make a 90º turn more rapidly”, he says. That would help the birds to dodge traffic as they exit or enter their nesting sites, or take off from the pavement, Brown explains. And that in turn would enable them to survive and produce more short-winged offspring.

Really cool stuff, and evidence of not only the amazing plasticity of birds but of the ability of some species to adapt to disturbed environments, a trait that may serve them well in an increasingly difficult world.

Greg Laden has a much more detailed take on the subject at 10,000 Birds.  The original paper is available here. 

North America's Oldest New Bird?

A review of Snyder and Fry, Validity of Bartram's Painted Vulture (Aves: Cathartidae). Zootaxa 3613(1):61-82. 

I bet it's been a while since you've seen a Small-headed Flycatcher, or a Townsend's Bunting, or a Carbonated Warbler. But I'm equally sure that most of us have heard of those birds, "nonce species" collected or claimed once or twice a couple of hundred years ago and never reliably encountered since.

And I'm almost as confident that there are birders who have never run across the Painted Vulture.

In 1774, William Bartram, the great Pennsylvania botanist and naturalist, was in Florida. There he found two vulture species "not mentioned in history," one of them "a beautiful bird,"

the painted vulture. The bill is long and strait almost to the point, when it is hooked or bent suddenly down and sharp; the head and neck bare of feathers nearly down to the stomach, when the feathers begin to cover the skin, and soon become long and of a soft texture, forming a ruff or tippet, in which the bird by contracting his neck can hide that as well as his head; the bare skin on the neck appears loose and wrinkled, which is of a deep bright yellow colour, intermixed with coral red; the hinder part of the neck is nearly covered with short, stiff hair; and the skin of this part of the neck is of a dun-purple colour, gradually becoming red as it approaches the yellow of the sides and forepart. The crown of the head is red; there are lobed lappets of a redish orange colour, which lay on the base of the upper mandible.... The plumage of the bird is generally white or cream colour, except the quill-feathers of the wings and two or three rows of the coverts, which are of a beautiful dark brown; the tail which is large and white is tipped with this dark brown or black; the legs and feet of a clear white; the eye is encircled with a gold coloured iris; the pupil black. (Bartram, Travels 150-151)

American ornithology has been skeptical: While a few authors (including, if memory serves, Roger Tory Peterson in the 1980 Field Guide) have been willing to believe that Bartram had seen and then incompetently described a King Vulture, most simply assume that his Florida bird is concocted of poor memory, rich imagination, and ignorance.

Now come Noel Snyder and Joel Fry with a compelling re-assessment of the evidence—some of it familiar, much of it new—for the historic validity of Bartram's Painted Vulture. Their argument is as simple as it is cogent: There is at least one earlier eighteenth-century description and painting, evidently unknown to Bartram, of birds resembling his (and differing in similar ways from the King Vulture); and none of the modern arguments against the credibility of Bartram's description bears up under closer examination. They conclude:

Together, these and other factors make a strong case for acceptance of Bartram's Painted Vulture as a historic resident of northern Florida and likely adjacent regions.... extinct by the early 19th century.

Forty years before Bartram's Florida discovery, Eleazar Albin described and painted a living vulture kept in captivity in London; the authors note that both Albin's text and his illustration (above) are a "close match" for the Painted Vulture. Particularly notable is the tail pattern, described (and, in the case of Albin, painted) as white with a black tip: the tail of the King Vulture, in contrast, is black, a difference mentioned expressly by none other than John Cassin in what Snyder and Fry call his "endorsement" of Bartram's vulture as "a species [otherwise] entirely unknown."  

Albin's painting and description are the strongest eighteenth-century evidence for the existence of the Painted Vulture, but the authors are also able to adduce other support, painstakingly gathered from a range of sources and evaluated with admirable care. A 1758 Histoire de la Louisiane describes a "white eagle" closely reminiscent of Bartram's vulture. Bartram himself depicted a fan possibly made of such vulture feathers in a portrait he drew of the Creek warrior-king Mico Chlucco. More tenuous, but still suggestive, is the evidence provided by the bird-shaped handle of a prehistoric bowl from Alabama, showing "a clearly vulturine or raptorial beak shape together with a projection on the forehead that could be a representation of the fleshy lappets of a King or Painted Vulture." Both the fan and the bowl, along with Albin's painting, are reproduced in the present paper's figures. 

In the second part of their paper, Snyder and Fry convincingly refute the arguments against Bartram's reliability in describing his new vulture. They defend the Quaker explorer against the charge that he was writing from memory (his field notes are no longer extant, but they are referred to in his other writings), and point out that the sixty years between Bartram's visit to Florida and the next ornithological expedition to explore the area was, sadly, plenty of time for an already scarce species to approach extinction.

A number of ornithologists, starting with the influential Joel Asaph Allen, have suggested that Bartram's vulture was in fact a misidentified Northern Caracara. The authors rightly dismiss this far-fetched possibility:

That any beginning bird student might construct a description resembling Bartram's painted Vulture based on viewing a Caracara seems extremely doubtful. That Bartram might have done so seems beyond all credibility....    

There is no reason, the authors conclude, not to accord Bartram's description the same serious consideration granted other naturalists from the same period, and every reason to believe that that description refers to a hitherto unrecognized vulture from the southeastern United States, whether a pale-tailed form of the more widespread King Vulture or, in Snyder and Fry's view more likely, a distinct species Sarcoramphus sacer (and not McAtee's sacra, as the genus name is grammatically masculine). 

What happens next? The AOU Committee on Classification and Nomenclature acts on proposals submitted to the committee's Chair, publishing its determinations each July. None of us will ever witness a scene like that in Narca Moore-Craig's stunning painting of hunting Painted Vultures, but if two thirds of the AOU Committee is convinced by Snyder and Fry's arguments—and I believe they should be—we will see in our lifetime the true "de-extinction" of a wrongly dismissed species.    

Spot Check

I hope I'm mostly preaching to the choir when I say that counting birds whenever possible (vs. just ticking species) is important for many reasons.  The folks at team eBird have summarized the importance of doing so and some basics to try when counting flocks in their excellent post, "Bird Counting 101".  For those facing more advanced counting situations they followed up with "Bird Counting 201".  Here I'd like to show one of my favorite ways to count big flocks of birds using digital photographs.

Bird photography is very useful beyond aesthetic reasons. For example, when documenting a rare bird or for use in identifying challenging species a few photos can be invaluable.  I have also found that flock shots (however janky) are great for counting bird numbers from the leisure of my laptop.  I know I'm not the first birder who has thought of this (indeed, one main way to census flocks of waterfowl etc. is to study aerial photos), but I'd like to share a few tips I've found to be helpful.

First, a great use for a zoom lens is to pull back to fit the flock into the frame.  Sometimes a modest point & shoot camera or smart phone may be even better than a telephoto if you are close to a big flock.  If you still can't fit the flock in, try to estimate how much of the flock you are getting in the image to use as your basis for multiplying your estimation later.  When I'm looking at an image on my computer, I like to use the paintbrush feature in Photoshop Elements (about any image processing software will have similar features), with the pixel radius set to about the body size of each bird.  This lets me count individuals by dabbing them each with a spot of virtual paint, eliminating re-counts.  I also like to change the color in sets of birds according to the general size of the flock (like every 10, 25, or 100 birds.)  This gives me a nice visual of each block of birds and helps me pick up where I left off if I lose count.  Not only does this give a really accurate count of the flock but I think it helps me improve my visualization of blocks of birds in the field if I can't get a shot to count later.  Here are a few examples of this technique that I've used to get a good count of birds in a flock.

 

 

The winter of 2007/2008 produced an amazing irruption of Bohemian Waxwings in Colorado.  Here is what I estimated to be about 1/3 of a flock in my Longmont neighborhood on 29 December 2007.  How many birds do you think are in this frame?

 

I arrived at 698 individual birds, each dabbed with a spot of color (in separately colored blocks of 100.) Click on the image to see the color dabs in higher resolution.)  Since I thought I was able to fit about 1/3 of the birds in the frame, I estimated the flock to be ~2100 birds.

 

Here's an example from last fall.  On 5 October 2012 an amazing overflight of Sandhill Cranes swept the overcast skies of Boulder.  Skein after skein of vocalizing birds traversed the city in the afternoon hours, and amidst my errands I swung into a Safeway parking lot to take a wide-angle shot of one wave.

 

To count the birds I tweaked up the brightness and contrast and then dabbed the birds in colored groups of 100, arriving at 378 birds.  By comparing this group to the multiple other skeins I saw flying by that afternoon I estimated my observation total at 2400 Sandhill Cranes.  Adding photos like this along with field notes to eBird checklists is a great way to make your friendly neighborhood eBird reviewer happy!!  

 

 

Like much of the United States, Colorado is in the midst of an historic redpoll irruption this winter.  On 24 November, 2012, I caught up to a large flock that had been reported frequenting Baseline Reservoir in Boulder.  When the flock picked up and whirled around I grabbed a shot with every bird in the frame.  Care to estimate the count before scrolling down??

 

 

 

 

In this frame I came up with 60 birds, here dabbed in color blocks of 10.  On a personal note, at the time I saw it, this flock was about triple the size of all of my prior cumulative redpolls in the state (a number that has since skyrocketed from several more large flocks I've encountered this winter.)

 

You don't even need a telephoto rig to try this technique- here's another Bohemian Waxwing flock (from Niwot, Colorado 22 Feb 2013) digibinned with my iPhone through the beta bins that I keep in my car.  I propped the binocular on my window (partially rolled up to achieve a good height) and clicked a few shots for a private census.  

This time spotting by 20s I came up with 160 birds in the cottonwood tree.

 

OK, ready for your homework?  See what you come up with on this one...  ◔_◔