BIRDING BY HINDSIGHT: A Second Look at MORC, Part 2

[Author's Note, September 2010 – As mentioned in the previous Hindsight, the  committee's name changed to Minnesota Ornithologists’ Union Records Committee (MOURC).]

All right, class, settle down and pass in your homework assignment. What homework?! You seem to forget last winter, when class was last in session (http://mbwbirds.com/mourc-i.html), you were given the task of naming those 17 species whose reports have been most frequently found Unacceptable by our beloved and respected Minnesota Ornithological Records Committee. You remember MORC: rhymes with – never mind.

To refresh your memory, the point of the assignment was that the more often reports of a species are turned down, the more likely it is birders have trouble with its identification. By studying these problem birds first and what might be lacking in the documentations provided with the records, the idea is you might then avoid in the future the most frequent difficulties others have had in the past.

Of course, it’s not quite all that simple. MORC primarily reviews species classified as Casual and Accidental on the state list, with Regular species voted on only when far out of range or season. As a result, Regulars are underrepresented in this survey, with only four of the 17 species always on the Regular list since MORC began its proceedings. By definition, they occur in the state every year — and, when you stop and think about it, it then follows they are probably misidentified much more often than Casuals and Accidentals.

Anyway, now that all your papers have been turned in, here are the 17 species (the numbers in parentheses indicate the total number of records judged Unacceptable by MORC). All have been turned down a total of at least seven times over the years, with the bird at the top of the list voted down 12 times. There is, by the way, no significance in cutting off this list at 17 or choosing seven as the minimum number of rejections. (Continuing down the list, there are five species with six Unacceptable votes, five others with a total of five rejections, 14 turned down four times, etc.; some of these will be mentioned at the end of this discussion.)

• Swainson’s Hawk (12)

Well, we have a winner! (Or is it the loser?) It might be expected that Number One on our list is a hawk, but it is curious it’s a Regular species and, thus, not normally voted on. The problem has been the large number of reports of it over the years from November into March, even though the species primarily winters in South America. Minnesota observers, however, at least seem to be getting better at learning this hawk’s ID and its seasonal status. As pointed out at our earlier class, this is one of those birds with fewer Unacceptable MORC votes in recent years.

So, just what is it observers might be confusing with the Swainson’s Hawk? Immature Bald Eagles, for one thing. Many 2nd- and 3rd-year eagles show both dark bibs and white under wing linings and could be mistaken for Swainson’s when relative size is unclear or not considered. More often, perhaps, Red-tailed and Rough-legged hawks are the culprits. Many Red-taileds have a solid Swainson’s-like brown area across the throat/upper chest, while typical adult male light-morph Rough-leggeds have a dark and definite band across the breast. And be aware that even some adult Broad-winged Hawks show a solid dark brown (and Swainson’s-like) bib.

• Mississippi Kite (11)

It should, perhaps, come as no surprise to find the first two species on this list are raptors, a group with a long history of misidentifications. And this near-Regular species is now almost annual in Minnesota (or allegedly so), resulting in frequent reports of it to MORC. Here, I think, the number of Unacceptable votes mostly resulted from the difficulties observers have had in their documentations, and not as much from any ID difficulties. I suspect a majority of the rejected Mississippi Kite reports involve inadequate descriptions of correctly identified birds.

Once you’ve seen this species in flight, you quickly notice how its flight style and profile are unique and not easily confused with anything else. By their nature, however, such characteristics are unfortunately hard to describe in words, no matter how distinctive they are. And, unless you have a close view of an adult, a Mississippi Kite’s plumage is not all that distinctive and relatively nondescript.

A postscript: The Mississippi Kite has the dubious distinction of being the only Casual or Regular species on the state list yet to be documented by a specimen or recognizable photograph. [Author's Note, July 2016 – There are now several records including photographs.]

• House Finch (11)

It’s been years since MORC has voted on this now-ubiquitous Regular species. But when the House Finch began showing up here as an Accidental around 1980, it was usually at someone’s feeder, and that someone was typically a casual birder not used to documenting bird records. As a result, MORC used to receive numerous House Finch reports — most of them probably accurate — with insufficient descriptions.

The problem was primarily with males and their potential for confusion with Purple Finches, but take a second look in your field guide at the females and — except for bill shape — note their similarity to Pine Siskins. Certainly, both male and female House Finches are still involved at times in misidentifications, but these are negligible within the context of how common the species is now in Minnesota.

• Black-headed Grosbeak (10)

While adult male Black-headed Grosbeaks are certainly hard to confuse with anything else, the records MORC has evaluated and had to reject have mostly involved young male Rose-breasteds. Especially in late summer, such Rose-breasteds have buffy and mostly unstreaked underparts — just like female Black-headeds, except for their hard-to-see pink under wing linings. Fortunately, Minnesota birders seem to have become more aware of this ID problem, since only two of all the Unacceptable records have come in the last ten years.

Hybrid grosbeaks are also a potential and most difficult problem on the Great Plains, and such hybrids have probably been seen in Minnesota. And females of both species — of any age and at any season — can occasionally show a confusing and potentially overlapping variation in the intensity of the streaking and of the buff coloration on their underparts.

• Ferruginous Hawk (9)

Well, that didn’t take long for another raptor to appear on this list! That makes three out of the top five species, with four more raptors still on their way below. And the Ferruginous Hawk, like all but one of the other raptors on the list, is currently a Regular species and not subject to an automatic MORC vote. Interestingly, none of MORC’s Unacceptable votes has come in the past ten years; however, despite this encouraging trend, I suspect too many observers are still mistaking other buteos for a Ferruginous.

Certainly, paler Red-tailed Hawks represent the biggest source of confusion for novice hawk watchers, who are simply unaware how white some Red-taileds can appear overall. Many birders are also typically unaware that a Red-tailed of any age, unless a dark-morph bird, normally shows white at the base of its tail, with white often extending as well towards the tail tip. And even a “normal” Red-tailed as an immature shows pale or even whitish panels or “windows” on the wings. (Indeed, immature Broad-wingeds and Rough-leggeds — and Red-shouldereds of all ages — also have pale wing panels.) It’s easy to see how a generally pale buteo with white on its tail and on its wings can be mistaken for a Ferruginous.

• Western Tanager (9)

As a formerly Casual species, the now-Regular Western Tanager used to be documented with some frequency, and its ID is not necessarily as easy as you might think. Molting male Summer Tanagers in spring show an odd mix of colors which can include a Western Tanager-like red head. More than once a Western Tanager report has come in to the hotline, been checked out, and resulted in the ID amended to Summer Tanager. And probably-correct reports to MORC of male Western Tanagers have had to be turned down when the written descriptions said little more than that it was a red-headed tanager.

It is also important to note an immature Scarlet Tanager of either sex can occasionally show narrow but quite visible wing bars. An Acceptable description of a female-plumaged Western Tanager, therefore, needs to include the width and color of its wing bars and the color and amount of contrast of its back — consult your Geographic or Sibley field guide for more tanager information.

• Ross’s Goose (8)

Now that the status of Ross’s Goose has changed from Accidental to Casual to presently Regular, MORC votes on it — both positive and negative — have become less frequent in the past ten years. However, the main reason for those frequent Unacceptable votes, the occurrence of intermediate or hybrids, is still out there. Scrutinize flocks of Snow Geese long enough looking for something else among them, and you’ll eventually turn up both plenty of Ross’s and some “in-between” geese as well.

My advice is to ignore overall body size when identifying a Ross’s. If you study published measurements of specimens, you’ll see there is overlap between the largest and heaviest male Ross’s and the smallest female Lesser Snow Geese. Concentrate instead on the Ross’s shorter-necked/rounder-headed profile and, more importantly, on its bill: straight and vertical base, lack of an oval “grinning patch,” shorter length, and bluish-gray basal half. And be prepared to see some bills with intermediate features — and to leave these as unidentified geese.

• Osprey (8)

• Broad-winged Hawk (8)

Like the Swainson’s Hawk, these two raptors (we’re now up to five on this survey) have always been treated as Regular — i.e., both correct and incorrect reports of them tend to escape evaluation by MORC. But they also attract MORC’s attention often enough since they share something else with the Swainson’s: the failure of many birders to realize how unlikely they are here in winter. Sadly, though, these two do not share the Swainson’s Hawk’s trend of fewer Unacceptable votes in recent years: they show no trend one way or the other. And, since each species has the same history of rejection, they can be covered simultaneously in this paragraph.

But not the same with these two, of course, are the other raptors which are the potential sources of ID confusion. I suspect that most winter claims of Osprey in reality most often refer to Rough-legged Hawk or Bald Eagle. Both Ospreys and light-morph Rough-leggeds may have similar carpal patches, although otherwise their under wing patterns are quite different. And sub-adult Bald Eagles can show a mostly whitish head with an Osprey-like stripe through the eyes.

As for winter reports of Broad-wingeds, consider that the very similar immature Red-shouldered Hawk is far more likely here in winter. Note as well that the pale tail bands on a Red-shouldered of any age can appear to be about the same width as the dark bands, just like a Broad-winged. Also consider the three accipiters, all of which can winter in Minnesota: when these raptors soar they can look quite buteo-like while fanning their banded tails.

• Gyrfalcon (8)

This raptor may be currently considered as Regular, but it is just barely so with only a single reliable sighting or two most years; in some previous years the Gyr found itself demoted to the Casual list. Part of the uncertainty of its status lies with the number of questionable sightings over the years, and unfortunately all but two of those Unacceptable MORC votes have come in the most recent ten-year period.

So what’s the ID problem, other than the obvious fact that it’s a raptor, which alone is enough to strike terror into any MORC-fearing birder? The primary difficulty is that Gyrs, sort of like Mississippi Kites, are difficult to describe with no obvious field marks to hang your documentation on. (Perhaps a white-morph Gyrfalcon isn’t so tough to tell, but this form seldom occurs here.) Be aware that a soaring Gyr can look more like a buteo than a falcon; more importantly, be aware that a Northern Goshawk in direct flight looks quite falcon-like and is about the same size as a Gyrfalcon.

• Whooping Crane (8)

Everyone’s heard of the endangered Whooping Crane, and, besides, it’s human nature for wishful thinking to sometimes cloud objectivity. (Objective, accurate observation may be more scientific, but it’s not as much fun!) So, it’s easy to see how this species appears on this list. No, a Whooping Crane doesn’t closely resemble anything else, but a large black-and-white bird like a pelican or Snow Goose is close enough. Not to mention Wood Stork, which is overdue on the Minnesota list. [Author's Note, July 2016 – There are now three records of this species.]

Keep in mind as well that a flying Sandhill Crane at some angles in harsh light can appear whitish with somewhat contrasting darker primaries. Leucistic, or abnormally pale, Sandhill Cranes are also a reality and could easily be mistaken for Whoopers. At least the trend with this species is positive, with fewer Unacceptable votes in recent years.

• California Gull (8)

Finally, a gull, and it’s about time! For if anything can confound birders more than a raptor, it has to be a gull — and all the worse if it’s an immature. As far as this species goes, juveniles and first-winter Californias look a lot like Herrings or Lesser Black-backeds of the same age, while second-winter birds are hard to tell from first-winter Ring-billeds. Even reports of adult California Gulls can cause ID and documentation problems: both fourth-winter Herring and Thayer’s gulls can also show both red and black spots on their lower mandibles, and Thayer’s Gulls normally have brown eyes like Californias.

Since this gull regularly occurs in the Dakotas less than 100 miles from the Minnesota border, reports of it will continue to be evaluated by MORC with some frequency. But let’s hope its voting trend continues, since none of the Unacceptable votes has come in the past ten years.

• Iceland Gull (8)

It’s time already for another gull, but the less said about this one the better. About the nicest thing about this nightmare of an ID is that the Iceland Gull was recently promoted to the Regular list. Consequently, and fortunately, MORC is no longer required to evaluate all reports of this alleged species. As veteran gull watchers learned years ago, you’ll go blind or at least dizzy trying to distinguish darker Icelands from paler Thayer’s of any age. Besides, everyone knows these two are the same species anyway, and what was the question again?

Ah, yes, how to avoid Unacceptable Iceland Gull reports. While you might be tempted just to call them all Thayer’s Gulls, birders already have enough problems trying to make valid Thayer’s IDs (see below). And this won’t work with Iceland-like Gulls which are too white to be a Thayer’s. Then you have to consider why they aren’t Glaucous Gulls, since a large male Iceland can closely approach a small female Glaucous in overall size. Worse, there is also the problem of albinistic gulls to consider in your documentations.

• Clark’s Grebe (7)

This species is similar to the Ross’s Goose in many ways. Both are most likely to occur in western Minnesota wetlands, and both quickly advanced through the ranks from Accidental to Casual to Regular status. As a result, both species then found themselves voted on and turned down less often in recent years. In the meantime, birders are still faced with the daunting possibility of encountering intermediate/hybrid grebes as well as geese.

And there have indeed been several documented records of grebes in Minnesota with characteristics intermediate between Clark’s and Western. Among the most disconcerting bird observations I’ve ever made here were the two occasions when a grebe viewed from one side had every indication of being a Clark’s: orange bill, eye surrounded by white, pale flanks. Every indication, that is, until it turned around to reveal a bird with a split personality: now it showed a Western-like greenish-yellow bill, dark feathering around the eye, and darker flanks!

• Prairie Falcon (7)

Now that the end of this list is within sight, we come to the seventh and last raptor of dubious merit. And it’s about time. One-third of Minnesota’s 18 Regular raptor species are included here, with raptors comprising more than 40% of this list of 17 species. To find raptors involved with so many Unacceptable records is simply, well, unacceptable.

At least with the Prairie Falcon we have an ID apparently giving birders and MORC fewer difficulties in the past ten years, although why this species so frequently causes problems in the first place isn’t so clear. I suppose some potential for confusion comes from richardsonii Merlins and immature tundrius Peregrines, both of which look relatively pale overall, especially in their Prairie Falcon-like head patterns. And it’s uncanny how a Northern Harrier can resemble a Prairie Falcon: yet females and immatures have similar dusky under wing linings, and when they glide into a headwind their wings take on a falcon-like aspect.

• Laughing Gull (7)

And we arrive here at our last serious gull ID problem, and one which isn’t getting any better: all but one of MORC’s Unacceptable votes have come in the last 10 years. Unlike the previous species on the list, however, it’s pretty clear where the ID problem primarily lies with the Laughing Gull. Even experienced birders are unaware that first- and second-summer Franklin’s Gulls can show a combination of a near-complete black hood and a solid upper wing pattern lacking that white area between the outer primaries and the rest of the wing. These end up being miscalled adult Laughing Gulls.

• Yellow-throated Warbler (7)

Probably the only reason this Casual species makes the list is due to its near-Regular status. Reports of it to MORC are nearly annual, and a fair number have been turned down over the years. This warbler’s field marks are pretty distinctive, though, and probably most of the Unacceptable records were simply correct IDs with inadequate descriptions. Lacking thorough documentation, a Yellow-throated Warbler report most often leaves the reviewers wondering why it wasn’t a female Blackburnian.

*          *          *

To be sure, there are many other species missing from this survey which give birders lots of difficulties. They may not always be the hardest birds to ID — in fact, most of these have seldom, if ever, been evaluated and rejected by MORC. But I suspect all-too-frequent misidentifications involve those listed below. Some of these species have been discussed in previous Hindsight articles, others may become topics in the future, and all of them are ripe subjects for some extra-credit research:

• Trumpeter / Tundra Swans

• any female duck

• Greater / Lesser Scaup

• any raptor not mentioned above, especially the accipiters, Golden Eagle (confused

  with immature Balds), and Peregrine Falcon (the “Whooping Crane Syndrome”)

• Spruce Grouse (Ruffed Grouse are often just as tame)

• Greater / Lesser Yellowlegs

• all the “peeps” (especially Western Sandpiper!)

• Short-billed / Long-billed Dowitchers

• “ring-billed” gulls (many third-winter gulls have ringed bills)

• Thayer’s Gull (molting, worn, or faded Herrings are an underappreciated problem)

• just about every other immature gull

• Common / Forster’s Terns (Forster’s are really the common tern here)

• Downy / Hairy Woodpeckers (even experienced birders can struggle with them)

• Olive-sided Flycatcher / Eastern Wood-Pewee / Eastern Phoebe

• any Empidonax flycatcher

• Loggerhead / Northern Shrike

• American Crow / Common Raven (especially in southern Minnesota)

• any juvenile swallow

• all Catharus thrushes

• Pine Warbler (confused with goldfinches as well as other warblers)

• Chipping Sparrow (especially in winter)

• any sparrow with streaked underparts and central breast spot (they’re not all Song

  Sparrows!)

• Eastern / Western Meadowlarks

• Brewer’s Blackbird (especially in winter)

• Hoary Redpoll

....Class dismissed!