BIRDING BY HINDSIGHT: A Second Look at Hummingbirds

Well, some of you may be thinking, this won't take long. After all, you say, here in Minnesota we've got Ruby-throateds and that's it. Of course, you're 99% right, since it's the only hummingbird around breeding in the eastern half of the U. S. But, if you take a second look at various state lists, other species turn up more frequently than you might have thought.  

In all, 23 hummingbirds are included on the American Birding Association's list of species recorded north of Mexico. For our purposes, though, we're safe enough disregarding four of them: Bahama Woodstar (four Florida records), Cinnamon Hummingbird (single records from Arizona and New Mexico), Bumblebee Hummingbird (two dubious Arizona specimens from the 1800s), and Xantus's Hummingbird (three West Coast records). That leaves 19 species to consider here, all but a couple of them regularly recorded from the southwestern and western U.S. And, of these, at least 16 have been seen in the eastern half of the U.S., with seven of them currently on the Minnesota list.

So, this might take a while, since the potential is there for a lot more than just Ruby-throateds at your feeders. Indeed, one could reasonably argue that most of those 19 hummingbird species could actually occur here – after all, since a Green-breasted Mango can appear in Wisconsin, and a White-eared turned up in Michigan....! But before briefly looking at the likelihood and identification of the individual species, there are some general considerations to think about.

Season and Location

If you're looking for something different, don't think spring. This may seem like odd advice, but all the records of all six extralimital hummingbirds in Minnesota have been from June to December. Other temporal advice would be to consider that normally Ruby-throateds don't arrive here until early May, and by mid-October the latest ones are gone. Accordingly, it would indeed be worth a second look at any hummingbird you encounter in April or from the last half of October on. And keep looking even into December if late fall has been mild: there are no fewer than four non-Ruby-throated hummingbird records that month.

Location, location, location? Feeders, feeders, feeders! As might be expected, hummingbird feeders have a virtual monopoly on all the rarity records. (I can remember only one record – a Magnificent – where the bird was attracted to flowers and insects rather than a feeder.) So, unless you want to spend your birding time staring at feeders, the best place for you to locate for seeing that odd species would actually be by your phone or computer – waiting for that report of a stake-out to come in from some puzzled or surprised homeowner.

Geographically, even though some rarities have appeared at northern Minnesota feeders, the southern part of the state would seem to have an edge. As mentioned earlier,  the potential for stray western hummingbirds turning up in the eastern U.S. seems almost endless, but that potential drops off as you go farther north, with Canadian provinces especially disadvantaged. Northwestern Minnesota might be the least likely place for something good to turn up: consider that adjacent North Dakota and Manitoba have just two vagrant hummingbirds on their lists (Rufous and Broad-tailed).

Identification Caveats

Adult male hummingbirds present few identification problems; you'll see that almost all the ID issues mentioned below involve juveniles and females. Still, be aware that the color of a male's throat (a.k.a. gorget) is a function of iridescence, so that what should be red or purple will often appear quite black if the bird is shaded or at the wrong angle with the sun. The same applies to a male's crown color, which is another key ID feature on some species. Be sure to note as well that pollen from flowers can discolor a feeding hummingbird's gorget or crown, resulting in confusion or even a misidentification.

Unfortunately, the thorny issue of hybridization does exist among hummingbirds, and this could certainly lead to inaccurate or unresolved IDs. While this problem would obviously be encountered most often farther west, it's still something to consider here, especially if that apparent stray Anna's or Rufous doesn't look right. Fortunately, that other vexing problem for listers – i.e., possible escapes – isn't much of a problem since the number of hummingbirds kept in captivity is almost negligible. (But see below about a possible Buff-bellied in Iowa proving to be another species escaped from captivity.)

Other Identification Hints

My best advice would be to take time to study all the Ruby-throateds you encounter, especially the juveniles and females. You will then be better prepared to detect another species when something about that hummingbird doesn't quite fit the Ruby-throated norm. Also, while discussing call notes here would be impractical and beyond the scope of this article, practice listening to a Ruby-throated's chip note – which I would describe as high-pitched, squeaky, almost like a soft Rose-breasted Grosbeak. Then, should another species turn up and start vocalizing, its different call notes might attract your attention and lead to a correct ID.

Two tools will often prove useful, even crucial, when identifying hummingbirds. One is a camera, especially a video camera. Since the differences between some species are subtle and hard for the human eye to detect on that constantly moving target hovering at a feeder, it may only be through photos or stills extracted from a video that an accurate ID can be made.

The other tool is less often employed, but, since some IDs (e.g., Rufous vs. Allen's) can defy even the best photos, a bander's nets might become necessary. Yes, there is the issue of possible stress on a netted hummingbird, but if a bander is unable to access a feeder with a problematic bird, the homeowner should be prepared for his/her hummingbird to remain unidentified.

References

"According to Hoyle" is the expression used to refer to games properly played by the rules. Similarly, this article's identification guidelines might be described as "According to Howell," since much of this information has been gleaned from Steve Howell's excellent reference published by Academic Press, Hummingbirds of North America: The Photographic Guide. I certainly recommend this book to birders seeking help with the ID issues not fully covered in this article.  

Another recommended hummingbird reference is in the Peterson Field Guides series, written by Sheri Williamson: A Field Guide to Hummingbirds of North America. I chose the Howell guide primarily because he is a known authority on many difficult ID issues, his book includes more thorough descriptions of vocalizations, and because his book's photos are larger and of more consistent quality and utility. The photos in Williamson's guide are smaller and sometimes only marginal in quality; note, however, that her book's range maps are superior to Howell's.

Though I haven't seen it, the video "Hummingbirds of North America" would also prove useful (but can't anyone come up with an original title!?). It's part of the Peregrine Video Productions series, written and narrated by Jon Dunn, Sheri Williamson, and John Vanderpoel, and it includes slow-motion footage, frame-by-frame stills, and call notes.

Finally, the Louisiana Ornithological Society includes a good two-part article on hummingbird ID on its website – http://losbird.org/los_news_188_99nov2.htm#7 and http://losbird.org/los_news_189_00feb2.htm.

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Following are brief accounts on the distribution and identification of those 19 hummingbird species mentioned above. Seven of these have already occurred in Minnesota, while the others have at least some potential of appearing as a first state record at your feeders some year. They are presented more or less in the order of their likelihood, with those at the end with probably little chance of straying in this direction (and, consequently, these tend to have shorter accounts). Note that "East" below refers to the eastern half of the U.S./Canada, i.e., from Manitoba, the Dakotas, Nebraska, Kansas, Oklahoma, and Texas (excluding Big Bend and vicinity) east.

I. Species on the Minnesota List

• Ruby-throated Hummingbird  

This, of course, is the default hummingbird in Minnesota, at least from May to October, and the only one most birders will ever see here. Consequently, the first question to ask yourself when confronted with a possible stray should always be, "Why isn't it a Ruby-throated?"

When seen well, adult males present few ID problems since there only two similar "red-throated" species: Anna's and Broad-tailed. These, however, are actually "rose-throated" (not ruby-red), and note carefully the chin color just below the bill: the rose-red on Anna's includes the chin, a Broad-tailed's chin is actually white, while a Ruby-throated's chin is actually broadly black.

Females/juveniles are another matter, and separating them from other species (especially Black-chinneds, Anna's, and Costa's) can be challenging, beyond the scope of this brief account, and readers should consult Howell or Williamson for complete ID information before claiming to see one of those three. There are, however, three basic ID points to consider with birds in this plumage:

1) Though I have not often noticed this on Ruby-throateds, there can be a buffy or rusty wash on the flanks. (Black-chinneds, by the way, are in the same Archilochus genus and can also show this color.) It is not as bright or as extensive as on a Calliope or a female/juvenile of genus Selasphorus (i.e., Rufous, Allen's, or Broad-tailed), and if visible it should serve to preclude a hummingbird of genus  Calypte (Anna's or Costa's), which would lack any such color.

2) A clear look at a Ruby-throated's folded primaries can eliminate a possible Anna's or Costa's. Its inner primaries are narrower and contrast with the broader outer primaries, while on an Anna's/Costa's all the primaries look basically similar in width with no abrupt difference between the inner and outer primaries. (See photos in Howell for illustrations of this feature.) As might be expected, though, the Black-chinned shares the Ruby-throated's primary pattern.

3) Contrary to some ID references, which claim Ruby-throateds always have green crowns while the Black-chinned's is duller and grayer, there is no consistent difference between their crown colors. Therefore, an Archilochus in Minnesota with a dull gray crown is still far more likely to be a Ruby-throated.

• Rufous Hummingbird  

Here is the most likely non-Ruby-throated hummingbird to show up here, since there at least a dozen Minnesota records (all between July and December), plus a few others classified as "Selasphorus, sp." (i.e., the small possibility of Allen's Hummingbird could not be ruled out). Indeed, this is by far the most likely vagrant hummingbird throughout the East, with only Quebec and Prince Edward Island apparently lacking any records.

Males with complete rufous backs and fully – or at least partly – red throats are safely separable from male Allen's, which "never" have all-rufous backs. Unfortunately, though, an occasional adult male Rufous can show an entirely green back and thus easily be mistaken for an Allen's.

The real Rufous vs. Allen's problem, of course, involves females/juveniles, and this remains the most difficult of all the hummingbird ID challenges. In fact, even the best photographs sometimes aren't good enough to safely determine the identity of some individuals, since the only solid difference between these two involves the precise shape and pattern of the tail feathers – features which may only be visible on banded birds and specimens.

A Rufous may certainly be more likely in Minnesota than an Allen's, but there are enough records of the latter in the East that likelihood alone can't safely lead to a positive ID. Obviously, you'll need to consult Howell or Williamson for analysis of this issue, but you'll find even the most authoritative references will fail to determine an individual's identification in some Rufous/Allen's cases.    

• Anna's Hummingbird  

With four Minnesota records (all during October-December) and records in at least other 12 Eastern states/provinces, including nearby South Dakota and Wisconsin, this species will probably reappear here. And if it's an adult male, the ID probably won't be daunting: see the Ruby-throated section for comments on the Anna's gorget and chin colors relative to Ruby-throateds and Broad-taileds. Note, though, that a male Anna's crown iridescence is often harder to see or more limited than its gorget color, making it then resemble a Broad-tailed.

Naturally, a female/juvenile Anna's is more difficult, but see the Ruby-throated account for comments on the Anna's (and Costa's) lack of rusty flanks and more uniform width of its primaries. Separation of Anna's from Costa's is equally challenging, but there are some useful differences. The Costa's tail is shorter, with its folded wing tips reaching or extending beyond the tail tip; only the Calliope has such a relatively short tail. A Costa's throat and underparts tend to look whiter and relatively unmarked; an Anna's throat is usually more spotted with patches of color, and its underparts (especially the flanks) typically appear washed with gray or even green.

• Green Violetear  

Even though this Neotropical species does not breed north of Mexico, surprisingly there are two summer Minnesota records, nearby sightings in Iowa, Wisconsin, Michigan, and Ontario, plus records from no fewer than 10 other states in the East. Refreshingly, the ID of this species is relatively easy, with males, females, and juveniles similar and distinctive in appearance. While its mix of blue and green colors may be reminiscent of a Broad-billed, there are enough obvious differences between these two species to preclude confusion.

• Calliope Hummingbird  

The sole appearance of this species in Minnesota (in November-December) seemed surprising at the time, although South Dakota has a record, as do at least 12 other Eastern states. An adult male's unique gorget pattern alone is certainly diagnostic, but, predictably, females/juveniles are more difficult. As mentioned above, its short tail length is a feature matched only by a Costa's, but also note the blunt, squared-off, less rounded tail shape compared to most other species. A Calliope also shows some rust on its flanks and under tail coverts, suggestive of a Selasphorus, but look again at the tail: unlike a Selasphorus, it shows little or no rufous and often appears all-black.

One last diagnostic feature worth noting on adult females (but not on juveniles of either sex): try to see that their white lores extend forward and above the base of the upper mandible, a subtle difference apparently shown by no other species.     

• Magnificent Hummingbird  

There are three Minnesota records, all in summer, which were indeed unexpected, given there are apparently only records from adjacent South Dakota plus five other states in the East. So, it may be awhile before another appears here, though it should again attract immediate attention when it does – especially if it's a magnificently plumaged male. And the superior size alone of a female precludes all other species except Blue-throated. But then, note the relative lack of white on its greenish tail (Blue-throateds have huge white corners on a bluish tail), and usually Magnificent has just single white spot behind the eye (compared with two longer stripes typically behind the Blue-throated's eye).     

• Costa's Hummingbird  

An even more unexpected vagrant was the male remaining for two months (September-November) at a Minnesota feeder a few years back: after all, while Costa's had been recorded in South Dakota, otherwise it apparently has never wandered east of Kansas and Texas.

An adult male Costa's purple crown and elongated gorget is a unique combination, but, when the iridescence is not apparent, a distinctive white stripe between crown and gorget will typically be obvious. As for the ID of females/juveniles, see the Ruby-throated and Anna's paragraphs which refer to the Costa's whiter flanks and uniform primaries width (compared to Ruby-throated and Black-chinned), and its shorter tail and relatively plain throat and underparts (compared to Anna's). One other subtle feature to look for is the Costa's straighter and more uniform black line through the lores; on an Anna's, the loral line tends to be more irregular in shape and continuity.  

II. Most Likely First State Records

• Black-chinned Hummingbird  

Although there has yet to be a Minnesota record, South Dakota and Ontario have recorded Black-chinneds, as have at least 12 other states East. A record here of this species would thus seem inevitable, and perhaps a female/juvenile or two has already appeared but escaped detection, given its close similarity to a Ruby-throated. As previously mentioned, both have inner primaries narrower than the outers, both sometimes show buff or rusty flanks, and both can show either greenish or grayish crowns.

While separating the two Archilochus females/juveniles may require some additional study in Howell or Williamson, try to see the following features if you see a suspected Black-chinned: 1) the blunt, wide, and more rounded tip of the outermost primary (narrower and more pointed on Ruby-throated); 2) the more pointed or "nipple-shaped" tail feathers (more rounded tips to the rectrices on Ruby-throated); and 3) usually a slightly longer and somewhat decurved bill (perhaps only marginally different from a Ruby-throated, but often distinguishable from the relatively shorter, straighter bills of an Anna's or Costa's).

• Broad-tailed Hummingbird  

This is another good candidate for a first state record, with Manitoba, North and South Dakota, and at least eight other Eastern states listing this species. As mentioned earlier, adult male Broad-taileds may bear a resemblance to Ruby-throateds and Anna's, but see above for their differences in throat and chin colors. In direct flight, the adult male's outer primaries produce a loud, shrill, high-pitched trill which is unique. (Females and juveniles, though, don't produce this sound.) But keep in mind that all hummingbirds can "hum" (well, duh!), though these sounds produced by the wings of other species are never as distinctively high-pitched or as loud as the Broad-tailed's.    

Females/juveniles, with rusty color on their sides, flanks, under tail coverts, and tails, resemble other members of the Selasphorus genus (Rufous and Allen's). But this color is generally paler and more limited in extent, and, unlike Rufous and Allen's, they should show no rust on the upper tail coverts. Note as well that the Broad-tailed's tail is not only longer than on a Rufous or Allen's, but it is also less tapered, blunter, and more squared-off with short central rectrices – somewhat like the shape of the much shorter-tailed Calliope.

• Broad-billed Hummingbird  

This colorful southeastern Arizona specialty might seem quite out-of-place at a Minnesota feeder, but there is good potential for one to stray here, considering there are records in South Dakota, Wisconsin, Michigan, Ontario, and three other states East. The blue-and-green adult male with its red bill would certainly attract even a beginner's attention, but females/juveniles could also be figured out given a decent view: these have a unique combination of some red at the base of the lower mandible, a white stripe behind the eye setting off a dark cheek patch, and a blue or bluish-green tail. It might be tempting to mistake one of these for a White-eared, but the "ears" of that species will always look whiter, wider, and more cleanly delineated.  

III. Less Likely Possibilities

• Allen's Hummingbird  

Though perhaps less likely here than a Rufous, the Allen's has still been documented in at least eight Eastern states, with Kansas the closest one to Minnesota that I'm aware of. Consider as well the real possibility that an Allen's or two may have already occurred here, but understandably passed off as a Rufous. As pointed out earlier, even full adult male Allen's/Rufous hummingbirds can present difficulties – to say nothing of females/juveniles, which often prove hopelessly indecipherable unless examined in the hand. So, please, let's move on to something easier to figure out, like a hummingbird in Iowa from Peru....

• Buff-bellied Hummingbird  

This South Texas specialty, as unlikely as it might seem, just might wander in this direction eventually, given the records from six states east of Texas, with Arkansas apparently the closest it's come to Minnesota. There was almost an Iowa record, though, in 1998, when one was tentatively reported at a Des Moines feeder. It was eventually learned this bird had escaped from a nearby botanical garden, and its identity proved to be a species from Peru: the Amazilia Hummingbird (Amazilia amazilia). This anomaly aside, however, male, female, and juvenile Buff-bellieds are all similar and distinctive enough to cause few ID problems.

IV. "Impossibilities"

• Green-breasted Mango  

So, what is this, a fruit or a bird? And even if it is a bird – one only breeding from Mexico south, no less – what does it have to do with Minnesota? With only a handful of Texas records and an odd North Carolina occurrence north of the Mexican border, there never seemed any potential for one to wander this way. All true, perhaps, until one had the audacity to appear last fall at a Wisconsin feeder and, in the process, to destroy our preconceptions of what was possible here in the Midwest. At least this hummingbird does not add ID insult to ego injury, since its plumages are distinctive enough to cause little confusion.

• White-eared Hummingbird  

With this local specialty hard enough to find in southeastern Arizona, it would seem to be another "impossible" vagrant in the Midwest, with records East only in Texas and Mississippi. But then one showed up in Michigan a couple falls ago: an event as improbable as, say, a mango appearing in Wisconsin! This species' plumages are similar and unique enough to present few ID difficulties, although, as mentioned above, there is some potential for mistaking a female Broad-billed for a White-eared.

V. Least Likely Possibilities

• Blue-throated Hummingbird  

Admittedly, the odds for this or any of the next four species ever showing in Minnesota are pretty slim – but I'll bet they said the same thing about a mango in Wisconsin. So, who knows? Anyway, Blue-throateds have wandered east as far as eastern Texas and Louisiana, and at least the ID is straightforward enough, with only the Magnificent (see above) looking somewhat similar.

• Violet-crowned Hummingbird  

As far as I know, East Texas is about as far that one of these hummingbirds has ever made it, so the potential seems even lower for this species to wander up to the Midwest. But the identification of this striking species is pretty easy, with males, females, and juveniles all similar in plumage, and note it's the only hummingbird that's entirely white below.  

• Lucifer Hummingbird  

The odds are shrinking even more with the third hummingbird in this section, with apparently no Lucifer records east of the Big Bend area. Should a male defy the odds, however, look for its unique combination of purple throat, decurved bill, and long forked tail. (The only other purple-throated species would be the Costa's, but that also has a purple crown and a shorter tail.) Females/juveniles have similarly distinctive bills and tails and have varying amounts of buff on the underparts, especially on the sides or center of the breast, while the buff that appears on some other species is limited to the flanks and under tail coverts.

• Berylline Hummingbird

Another species with no records in the East, which is not too surprising given that it's barely regular in southeastern Arizona. When seen well, its ID presents little problem, with males, females, and juveniles all similar in appearance. About the only similar species would be Buff-bellied, but a Berylline differs by having little or no red on the bill, a buff wing patch, and a dark, non-rufous tail and rump.

• Plain-capped Starthroat

A barely regular southeastern Arizona rarity, this is yet another hummingbird with no precedence for appearing in the East. Should one ignore the range maps, though, it would stand out in a crowd with its unique white patch on the lower back, broad white malar stripe, and relatively long and straight bill. And, if an adult male, a rosy-red throat patch would be evident.

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Well, sorry to put you through all this, especially those readers formerly content with just enjoying the hummingbirds at their feeders and assuming no identification headaches would be involved. Now, thanks to me, you'll have to start worrying about pollen discolorations, chip note differences, inner primary widths, rectrix shapes, loral patterns, and all the rest. And isn't hard enough just to see the bird in the first place as it zips by – how are you supposed to examine its lores? (It's almost enough to make you yearn for the good old days of dowitcher ID and their loral angles.)