(Archive: Fun with Accipiters) 3 November 2009, Tuesday To recap: The next laws — all, also know as the Laws of Thermal Dynamics — get into the application of experience to reining in our human tendencies for making the worst of an observation situation, while expanding our precision and enjoyment in the moment. The worse part in the situation, with young or new birders, is when finally a new species is seen well... it's disappointing to check the life list and see the thing already checked off. I've always liked this quickie definition of knowledge: knowledge is information plus experience. "She's a knowledgeable birder." Like the sound of that? Read on... Picture a thoroughly suburban bird feeder, say on Long Island, with a sparrow-sized reddish bird at it. The phone rings and the new feeder watcher wants to 'alert the birding media' that they have a Cassin's Finch in their backyard. We go from there to Purple Finch and begrudgingly arrive at House Finch after much debate and disappointment. It's a familiar tale for those of us who have spent any time at a nature center or on-call with a bird club — both in my case. It's just human nature: "the newer the birder, the better the bird." In the field, for birders who have a full year's adventuring and are not new to birding, new also means, new to that species, or even new to that whole group of species. Working through the newness presents a unique puzzle each time a new bird is encountered, until. Until the information and the experience become knowledge. Each birder is different when it comes to crossing this threshold in building up a knowledge base. Legendary ecologist Robert MacArthur, who with EO Wilson, wrote The Theory of Island Biogeography (1967) put it this way in Geographical Ecology (1972), a book about detecting patterns in the face of complexity: The only rules of scientific method are honest observation and accurate logic. Wow. Keep the first two Laws in mind and be honest with yourself about what is possible, probably and therefore likely.
And from my little survey, guess what, many people are sure they have a Goshawk — the least common accipiter — at their feeder, or along the roadside. And guess what, it basically never is. Of course, the Cooper's Hawk has become a very common yard accipiter, with its delicate streaking that is concentrated on the upper breast and then thins and fades downhill from there. The Sharpie and Gos are thickly and thoroughly streaked. By the by, seeing an image or actual Goshawk shocks most seasoned observers. It is a distinctly spotted beast in its markings. I'll have a flight shot of a Gos, here on Friday accompanying the bad ID hall of fame post. I'm not going to put up hundreds of words here and now about this complex, just check out the crystal clear hard work of Wheeler and Ligouri. Some hawkwatchers never lose their new car smell (that's a bad thing in the context of the Third Law). A fleeting glance at a perched hawk while going around the sharp curves of a highway off ramp by a fellow in eastern Mass caused me to hawk-up a big web loogey called Wintertails. Started in '02, it has careened across twentysomething pages and several years. Concluding, the 3rd Law of Birding — the newness of someone else — comes into play when deciding whether to chase a sighting or vouch for the reporting of others. Inexperience with a species or its kin, enters into ARC decision-making. Of course, it should factor in when it comes to announcing, your own observations!
6 November 2009, Friday
This is a classic scene from Woody Allen's Annie Hall (1977 ), and as Woody says, wouldn't we all like to have the authority in question step out and correct another party right when we need them. Only in the movies, you say... or maybe it can happen in hawkwatching!
Now it is a lot of work and promises full disclosure to put the photos online, for all to see and this hawkwatcher/hawkwatch did just that. But, it's a new dawn and the Rockfish Gap accipiter 'quiz page' was posted to school us, not ask for input, really. The problem was that the feedback from the book authors cited and many other elite birders was unanimous — not a Goshawk, but a Cooper's Hawk. The bird is still labeled a Goshawk because, all evidence to the contrary, they simply deny it. Let's see if I understand their logic: on the one hand, here's the reference material to support our identification; on the other hand, all you guys disagree, well you weren't there and didn't see the UFO, we did. Compare and contrast the quiz bird with my (clickable) image of an actual Northern Goshawk. For every hundred hawk images I get to look at and comment on, there is rarely even one that ends up with the image taker offended or refusing to consider the identification points presented clearly and respectfully. It's always the influences of some old and in the way hawkwatch or watcher... akin to deniers and safekeepers of the stiff and old everywhere (idea-wise). So now, the "Fun with Accipiters: return to Virginia" movie-in-your-head sequel. And I'm Woody. The same folks have some other hawk images online, all correctly identified except for the Sharp-shinned Hawks where all three hawks are not Sharpies, not even one of them. All are Cooper's Hawks, likely all males (with the Coop images being represented by females mostly, so there's that). I emailed the source of the images and got back this: Thanks for your comments. I reply in two parts, first just to clear up the out-of-date info that square and even notched tails are a Sharp-shinned Hawk tell, I make reference (below) to how Wheeler handles the square issue in the text and then shows a Cooper's Hawk image with a notch too. FYI, especially adult male Coops will display a squarish tail, even flying, with a dent in the center perched. Here's my email back with text and image, exactly cited: Regarding that one perched bird, check Plate 197 in Wheeler 2003, Eastern NA -- it's a pretty good match. Ahead of that, his Cooper's Hawk text, now contains: "Tail can appear square-shaped when closed...", page 172. For the three birds, represented by four images, I continue in my next message to lay out the case for Coop over Sharpie, but no reply to this info, you can play along at home comparing this info to the images: The first and third of your Sharpie set are young
birds: Another oldie but no longer goodie is the accipiter big head equals bigger size/species. Like bears... wait for it... the head size maxes out, so a really big (male)bear will have a tiny head, proportionately. In most of our hawks, the females are larger than the males, so the normal-sized head will look tiny on the large females. For an example of this here and now, take another look at my image above of a the young (female) Goshawk: on that body, the face/head looks freakishly small. We're not holding this bird up next to a Cooper's Hawk, just look at the shrunken head on this beast. This big bird, small head thing works on most accipiters and buteos (see the two Redshoulder picts below). Snowy Owls are one of the best cases: males have this bulbous head and then seem to just taper to the tail from there — like a nightjar. The female Snowy is a loaf of bread with a tennis ball on top. I'll come back around to my point with other photo illuminations down the road.
16 November 2009, Monday
Just like at a hawkwatch, but different. This focus flips the effects of space and time by visiting the same places over and over... a route, a routine, a ritual. There's a rhythm to all sorts of things that's not rote, but all about extreme attention, the paying thereof. For hawks, I use a car; for mushrooms or animal tracks, I walk (crawl some). Always though, I'm employing the old and familiar to see new stuff. Our tendency is always to go someplace else, we say this is to avoid boredom... because you only go around once in life, and apparently it's the easiest path. Over and over is harder than, over there. In this sameness, the new and the amazing will enter. Give it a try. In eastern MA, I sort of stumbled into this, maybe through my play as a student and teacher of Tai Chi. More likely this was a meeting of the minds. But I came to studying the very familiar: American Kestrels, Red-tailed Hawks, Thoreau's Nine Acre Corner and so on. All common and I made them even more familiar, intimate. Search it out... keep this idea of wild intimacy, playfully, in your peripheral vision. 4 December 2009, Friday
Jerry Stiller's Frank Costanza character is a man with a move. If you are under fifty years old, you might need some background: the front seat of the majority of cars used to be a couch (no bucket seats, as they were know in the day), seat belts weren't installed in most cars until the early '70s (not required to be worn until later), therefore movement was unrestricted in the automobile of Mr. Costanza's day (safe and sex were in another context back then). It was a common practice for men to protect both women and children from lurching forward as the driver stopped abruptly, by the extension of the right arm. But it was also a move on date night. The Seinfeld Science theme, is clearly aimed at poking fun at worthy causes. I hadn't thought much about one silly idea in hawk migration studies until it lurched back onto the highway in a recent HMANA blog entry: Is this due to there being fewer redtails, or as in the case of the Sharp-shinned Hawk, are more Red-tailed Hawks migrating shorter distances, wintering farther north, or even wintering on their breeding grounds now than in the past? Short stopping entered the raptor lexicon as Hawk Mt.'s "move" when Cape May declared Sharp-shinned Hawk numbers were in "free-fall" according to the largest dataset of Sharpie numbers in the known universe. After being, shall we say, rear-ended at the 1988 HMANA Conference at Cape May by Paul Kerlinger's presentation centered on a very simple, but striking, line graph showing the decade plus descent of Sharp-shinned Hawk numbers at Cape May Point, I remember the question (to which he already knew the answer) ... was Hawk Mt. seeing this at their station? Among us hawk folks at the time, this was high drama as the answer came slowly from the back of the room that they were not detecting a decline, but it might be the nature of the age classes — immature birds at the coast and adults on the ridges — causing a lag, and they would have to look into it. Kerlinger was well-known for poking those around him with the sharp stick of his intellect, and at this point, he was thoroughly enjoying his home field advantage. The eventual Hawk Mt. article had enough hedges in it to be a movie location for a Jane Austen adaptation, and every single hawk counter, bander, and ornithologist, that I asked about it (granted, a sample of thinking biologists) gave the idea of short stopping its due, not for science, but for grand slicitude... it was a clever retort to say the problem was solved, by not actually being a problem, you see, there's no real decline going on. The real stink eye though was cast their way for using Christmas Bird Count data to make the case. But also: add some small numbers to some even smaller numbers, regress the bejezus out of that mean, sell it with a set of steak knives, and it's still don't make your case. What, steak knives without a case... no sale. The problem with using CBC data for Sharpies, in addition to the very small numbers compared to the loss of birds at Cape May, is the question of identification. If there is a sample group of birders less able to tell Sharpies from Cooper's Hawks than hawkwatchers, it would be Christmas counters, especially feeder watchers! I guess I have a problem with using CBC data for anything (for which you don't already have an answer through other means), but a hawk count conducted over a three-week period by observers looking out their kitchen windows, while others work out the ID of perched birds flushed around a corner, well, is just asking for it. HMANA's Hawk Migration Studies published a very readable and straight to the point piece by Nick Bolgiano in 2005. Nick examined a hypothesis that had been in the wind for a couple of years. As many daily hawkwatch counts began on the downside of the 1970s spruce budworm infestation, it took some time for the events to also drag down the populations of the "budworm warblers" (Tennessee, Cape May, Bay-breasted), and with them the budworm warbler raptor — the Sharp-shinned Hawk. Nick guides us along the hawkwatch site numbers (mentioning that two graphs are used because of the 3x scale difference needed to accommodate the Cape May numbers). The CBC data is looked at, but the warbler numbers are graphed using Breeding Bird Survey data from eastern Quebec! Everything just overlays and synchs up, as he unfolds this story. Nick has provided this paper in a PDF for the first time, and you can read it here or save a copy for later. While the spruce budworm hypothesis has been duly noted in all the Hawk Mt. work on the status of the Sharpie, including the venerable BNA species account, there's still this on their website today... haven't found those hedge clippers yet: Sharp-shinned Hawk populations may have declined in eastern North America over the last 20-30 years, as suggested by declines in migration counts in the northeast and near the Gulf of Mexico (particularly the Florida Keys). Evidence from CBCs, however, suggests that the declining migration counts may be due, at least partially, to migratory short-stopping.
23 November 2009, Monday To
recap the Laws of Thermal Dynamics:
You say, avian records committees do it all the time. With a records committee, they weren't there, so they're like the jury system: not direct witnesses to the crime, but will take in all the evidence and render a verdict. The good news is that more and more reports of rarities are coming in with supporting digital images and many ARCs are both requesting and actively seeking the photo documentation. Back to the scene of the crime: six hawkwatchers concur on the ID of an accipiter and someone marks the sheet with a pen, a seventh birder says nothing. Content with the vote five of the original six move on to other matters... other birds, local sports team highlights, lunch, but knowing this Law of Birding the sixth turns to the seventh. The Seventh (not their real name), waiting patiently for the look, returns a rye smile and the vote is overturned, at least in the mind of Mr. Six, who heard the silence (it's that zen thing again). The hawkwatch might be a social activity, might be science, but like gravity, you can't overrule the science with a potion of friendship (friends don't let friends make bad calls). This is another one of those laws where knowing the birders is as important as knowing the birds. And you want to be the birder who knows enough to look for help beyond your peers, even if they give you your own vote!     Wayback Machine: Whack-a-mole
Staying away from the facts is important and however enlightened we think we are, all of us gravitate to those whose point of view agrees with ours, studies say. For Old Testament hawkwatching that means staying away from professional counters and their sites. Plus each and every time a factoid about the difficulties separating the two species is floated, well, these birders are quickly onboard. "Wayback" posts are about things already written. That will be the meat of the post, but let's add a couple of side dishes... for the holiday. Over a decade ago, I used "current events" as a sarcastic pointer to the old and in-the-way ways... if our primary mission was protecting what we loved watching, then keeping up-to-date shouldn't be an issue. Here's a quickly timeline: Late 1970s: Pete Dunne writes a piece on telling
Sharpies from... Kestrels! 1980: Derby Hill NY, a Spring site, has a terrific accipiter season, with a 13:1 ratio (7974 Sharpies, 618 Coops). Keep this number in mind when you get all the way down to 2009. 1995: I printed my annual color handbill with a Current Events rant quoting the eastern MA hawk org newsletter with out-dated ratios and reference to one of those "new studies" that allowed for the accipiter coin flip to continue. There was an editor's note inserted to provide an "official" decree: MR. ED NOTE OF EASTERN MASS. WRITES: 2004: There are laws according to the Old Testament of Hawkwatching. On Sept 11 '04, the following was contained in a report from Blueberry Hill MA. Detection of humor in this offering is noted, but their season's final ratio (2009 too) bowed to the teachings, nearly so: An anomaly in the count: we logged 5 Cooper's Hawks and 11 Sharp-shins, a signal violation of Kellogg's Commandment ("Thine ratio of Cooper's to Sharp-shinned Hawks shall not exceed the tenth part.") This was prelude to the Old Testament's magnum opus, in reply to a birder's email about the subject of Sharpie and Cooper's Hawk ratio, which is really about deploying new information re: identification and thus having water run uphill from the coastal sites, with their young professional counters and banding stations (where ID is measured). Interesting, the total of all these numbers equals a couple of nice days at Cape May. Even more interesting, this data toss doesn't include New England's premiere accipiter site, Lighthouse Pt. CT:
Undated: Being the last week in September, when juvenile male Cooper's Hawks are moving on the heels of the young female Sharpies across New England, the year wouldn't matter for this one (SS:CH) — East Shore Park CT-- 90:9; Lighthouse Pt. CT-- 350:75 — these sites are a mile or so apart, and no other factor plays into these shockingly different ratios, 10:1 vs. 4.7:1, other than to say one count was Old and the other New Testament hawkwatching at its finest. The guy at East Shore has his name in the Old Testament (along with the fellow who compiled the numbers in the '04 email above)! Want to be scientific, sure. Stand one person from each site side-by-side and you'll get these results on just about any day. The only factor in play here is knowledge (information, plus experience with that info), as we see in this next entry... 2007: At the Plum Island Hawkwatch, this study in non-science took place... sorry I missed it, but it is a scene I've observed there so many times. Speaking of side-by-side, two groups counted migrating hawks from the same location (just meters apart)... here we go — the hawks at Plum on this May 1st morning were all low and accessible to both groups, so we should achieve similar results, right?! Those there to specialize in the hawks, reporting to Hawkcount.org via official forms, and so on, had half as many hawks as three birders (yes, one of them is easily one of the very best birders in MA and another hosts the website on Plum sightings). Still. I've distilled the divergent counts, again same day & time frame, from an email posted on Massbird: Sharp-shinned Hawk: hawk experts - 6; birders - 40 First, It's clear the "official" hawk count is useless for accipiters, those conducting the hawkwatch didn't have a clue and missed a lot of birds. The falcon numbers are trash can-worthy as well. After the hawkwatchers demurred, in a responding email, that it wasn't likely that the lead birder made any errors, the count has not been updated or altered to this day. In baseball terms, no asterisk next to the report. 2008: ABA Online Bird Quiz for October is your classic hawk in flight, scroll down to see the vote tabulation by species. 2009: Where the word of the day is "intriguing." And "seeing" is used, where "identifying" might be more accurate and honest. As you read the linked piece for intrigue, refer back up to that Derby Hill 1980 ratio. While not everyone can identify everything and some are better than others, the information needed to tell Sharp-shinned Hawks from Cooper's Hawks — the various ages and sexes — isn't controversial, and hasn't been for a very long time.    
15 January 2010, Friday
But, again, telling our three accipiter species apart is not controversial, just a skill set known better to some birders than others through facts and experience, where these facts do not include: long or short tails, round or square tails, notched tails, fierce looks, etc. This stuff varies enough betwixt and between the ages and sexes of these species to work, except when it doesn't. This will not be a comprehensive ID clinic... as Brian Wheeler's Raptors of Eastern North America (2003) volume covers it completely. The oldest image set here was posted by Phil Brown back before Christmas. It's of an adult male Cooper's Hawk with a lovely dent in the center of his nearly closed tail. From the back and fully relaxed, the tail on the Coop would look square, dented, and not that long... being a male of the species, either one. The bird is pretty riled up and has the hackles up which lengthens the head, front-to-back, making the eye appear set farther forward than it would on a relaxed crown. Phil put this known Coop on his website as one of a few Cooper's Hawks he's had visiting his yard. Another Coop image set was posted on Massbird by Erik Nielsen in the new year, originally he had it labeled as a Sharpie, because the head's rounded here making the eye position a bit harder to judge, and the gaze calm... not angry. But the dark cap contrasts with the nape of the neck heading us in the ID direction of Coop. In addition, the wing is opened enough to see icy gray bars on the secondaries, while the primaries are blacker. A lot of other possible puzzle pieces, some useful – some not, are mentioned in the discussion and that's perfectly okay, as long as the true stuff wins out. With an update, Erik has now included a summary of the information he received from other Massbird readers atop his images, very nice. Erik's other Cooper's Hawk, clearly a different bird, is like Phil's bird showing a lizard-like head shape by way of the textbook raised hackles and a very pale breast, often a Coop tell. Looks too like it was photographed on a cold day (very puffed out appearance). If you like your Coops with long broad tails, here's your chance to see the opposite of that. If this tail were a tie, you'd be wearing a jacket with the sleeves rolled up plus the collar up and cool... see Road House (1989) with Patrick Swayze, Sam Elliot, and Kelly Lynch... as Dalton, Wade Garrett, and Doc. Both posters received many private messages discussing the images, and both summarized this info. For what it's worth, the two public posts were not so useful. The first one here all depends on whether the bird has flattened out the head... or not (and as Erik learned, that's a Coop option, not a requirement) and the primary reason this accipiter was missed as a Cooper's Hawk on the first go-round was the non-reptile looking head shape... kind of looks Sharpie-round. BTW, instead of the position of the eye (which we now see can move about) work on a sense of the size of the eye on the bird's head: where the smaller species will have the proportionately larger eye. One last field mark is the placement of the eye on the head being forward of center creating a fierce look while Sharp-shinned has the placement of the eye centered and with the rounded head gives quite a gentle(r) look. Back noise — white feather edging on the upper wing surface— mentioned in the post below: is greatest in young/brown Northern Goshawks where it can be extensive; present in many juvenile Cooper's Hawks as upper wing covert flecking (although it's hard to see in late Spring when the back of this species can fade to a light sandy brown); and immie Sharpies' upper wing surfaces are often noted for their smooth, not noisy at all, almost spray-painted look. Perched, the presence of a few large spots has been associated with the Sharpie, but immie Coops can have something similar, so there's that. But-but, the images in question are all blue-backed adults, not immature accipiters. So, huh? Eric, excellent! I like everything you said. To the second point above, Erik's two sets show both birds with red or nearly red adult eye color that all three of our accipiter species attain eventually/mainly, so I don't know if this public poster needs a new monitor, or a second look!
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