Tuesday, January 13, 2015

Great Backyard Bird Count -- Middle and West Tennessee Cheat Sheets

The Great Backyard Bird Count happens this year on February 13-16, 2015 (as always, Friday through Monday of President's Day weekend). Since this event attracts a lot of people who are still learning to identify the common local birds, I've prepared a couple of "cheat sheets." These shows the most frequently reported GBBC species in Middle and West Tennessee. Here are the 49 most frequent species in Middle Tennessee (click to get the full-size image):

And here are the 56 most frequent species in West Tennessee:

As you can see, many species are in common between the two, but there are some differences since West TN generally has more open country and more wetlands. For these purposes, West TN begins at the Tennessee River corridor from Pickwick Lake to Kentucky Lake, including bottomlands on both sides of the river and the lower parts of the Cumberland in Stewart County and the Duck River Bottoms in Humphreys County. The images are collected from Wikimedia and are public domain (as are the cheat sheets themselves). If you are a novice birder, please do not use this as your only identification guide! Please use it as a supplement to one of the many good comprehensive field guides. My intent is to get you pointed in the right direction and help with some of the most common confusions, not to give you definitive identifications. The odds are good that you might find at least one additional species that is not shown on this page. Note also that these images are not to scale; the goal was getting them to fit on the page, not showing the true relative sizes of the different species.

Saturday, August 10, 2013

Steamboat Geyser, 1982-1984

This is one of those very odd coincidences. We've been working on bringing one of our few remaining "junk" rooms into service, which involved going through a lot of stored things. Among these, I found my photos of the two eruptions of Steamboat Geyser in Yellowstone, the world's tallest active geyser, that was lucky enough to see in 1982 and 1984. Well, I say lucky, but I substantially improved my odds by camping out on the viewing platform for many, many days. I decided that I should scan these images and post them online so they would be available, since there are not a lot of good photos of Steamboat in full water. It is extremely irregular, with intervals between eruptions having been as short as 5 days and as long as 50 years.

Tonight as I finished cleaning up a few of the images, I discovered that Steamboat erupted again just last week (July 31) for the first time in 8 years! So, far more timely than I had anticipated, three shots of two eruptions from September 6, 1982, and July 6, 1984 (clickable for larger version):

1982, early in the water phase, viewed from the boardwalk at the bottom of the hill

1982, full eruption, viewed from the traditional photo op spot

1984, full eruption

In full force, Steamboat is not just an amazing display of power, it is also a thing of immense beauty. The south vent (on the right) throws up a solid curtain of skyrocketing chevrons, while the north vent (on the left) reaches with its delicate fingers to incredible heights. Notice that in the 1982 photos, you can see one of these fingers perched at the very top of the giant steam cloud.

The 1982 eruption happened near noon on a post-card warm and cloudless day during the Labor Day weekend -- notice how the foreground spectators are dressed. Dozens of people were on the viewing platforms when the eruption began; hundreds may have seen at least a part of the water phase. The 1984 eruption was a moodier experience, in the morning, with more steam, filtered backlight, and only two or three of us on hand to watch as the first jets from the north vent began their heart-stopping climb towards the zenith.

ADDENDUM: I've gotten together a few more of the images from 1982:

I don't know for sure whether this was the morning of the eruption, but it was around that time:

It was a typical scene on the viewing platforms during nice weather in those years, when the odds of a major eruption were enough that people would dedicate time to sitting and waiting.. and waiting... and waiting...

Waiting for this:

Looking up from the lower viewing platform as the water climbs and climbs. This image is from the first moments of the eruption, when the shock wore off enough to remember I had a camera in my hand.

As the rain of geyserite approaches the upper platform, the spectators flee:

The sound track to this would run something like "Oh my god, oh my god, is this it? Oh my god this is it! Oh my god oh my god oh my god!" The experience from the upper platform is actually one that must be had, rain of silicate-laden water and all, and many spectators do venture back up there to get drenched. It is quite close to the north vent and almost directly in its line of fire, so at full water the top of the water column is indeed right overhead.

When the wind is from the west, as is normal, the lower platform remains dry and packed with people:

This shot is from late in the water phase as the steam is beginning to increase. At this stage you can still hear the person next to you; but the chest pounding roar of full steam phase soon grows and swallows up most other sound.

Sunday, March 31, 2013

Tennessee Bird Records Committee accepts Hooded Crane

As committee chair Kevin Calhoon recently announced, the Tennessee Bird Records Committee has voted to accept the 2011-2012 occurrence of a Hooded Crane at Hiwassee National Wildlife Refuge in Meigs County, Tennessee, as a wild bird. The vote came after over a year of research and discussion. Though the vote was split 5-1, the spirit of "reasonable people with the same information can reasonably reach different conclusions" prevailed and the discussion was respectful and without rancor. This was the third report of this species in North America; it is widely felt that all three records likely pertain to the same individual bird. What is almost surely the same bird also appeared in Indiana a few days after it was last seen in Tennessee, making a total of four occurrences in four states. The bird's stay in Tennessee was the longest of the four, and it was seen by far more people here than at any of its other stopovers. Hence it seems fitting that we are the first state to formally act on the species, making this the first BRC-accepted record of a Hooded Crane in the New World. ***EDIT*** I've just learned that Indiana accepted their record also, so we were not the first! Ah well. Not sure why the Indiana vote seems not to have been widely known.

I was in the majority on this vote (which has not always been the case on other recent split decisions!). The species identification was never in doubt, so the only question was whether the bird was of wild or captive origin. As is often the case, there was no direct evidence one way or the other, so we had to make our best judgement from circumstantial evidence instead. This raised the issues of standards of evidence and review philosophy, about which many different opinions were expressed in discussions on blogs and listservs. Some people advocated a "presumed wild until proven escapee" approach, while others advocated the opposite. Either way, this also raises the question of what the standard for "proof" is: Beyond a reasonable doubt? Beyond a shadow of a doubt? The preponderance of the evidence? If you will forgive a bit of legalistic philosophising, I'll describe how I approach this.

In general, and in this case specifically, I invoke the old standby of "When in doubt, leave it out." This applies equally to doubt about species ID and doubt about wildness. Many people seem to accept this criterion more readily for ID than for origin; but to me they are exactly equivalent. As for what constitutes "in doubt," I believe that the standard should be the time-honored "reasonable doubt." Expecting proof beyond all doubt is an impossible standard, as there is almost always some scenario that can be imagined and invoked to explain anything. So what is a "reasonable doubt?" I find this definition from the Supreme Court of Canada to be the most instructive:

"A reasonable doubt is not a doubt based upon sympathy or prejudice, and instead, is based on reason and common sense. Reasonable doubt is logically connected to the evidence or absence of evidence. Proof beyond a reasonable doubt does not involve proof to an absolute certainty. It is not proof beyond any doubt, nor is it an imaginary or frivolous doubt."

I also think that the questions should be, "Is this bird correctly identified?" and, "Is this bird wild?" The questions should not be, "Is this bird misidentified?" or, "Is this bird of captive origin?" The difference might seem trivial, but if you think about it in depth you will see it is not. Suppose you have someone claiming a California Gull based on its having been bigger than a Ring-billed Gull and darker on is back, with no other details. If your question were "Is this bird correctly identified?" you clearly would have reasonable doubt and would conclude the record should not be accepted, since many other species of gulls could fit that description. On the other hand, if your question were "Is this bird misidentified?" then you would also have reasonable doubt (it could be a California Gull based on the description), so you would not be able to reject the record. Obviously the former conclusion is the appropriate one for a BRC member to reach.

Getting back to the Hooded Crane, the question is "Is this a wild bird?" My initial reaction on first hearing of the record was that it probably was not; this seemed like "common sense." However, without investigating the report further, this is in fact a doubt that is based on "prejudice" (see above) not on "common sense" and "evidence." And as I did examine the actual evidence (circumstantial though it may be), I found my "reasonable doubt"about the birds wildness growing smaller and smaller.

To go through it in detail, I felt the "wildness" question could be broken down into several more specific points. First, what is the nature of the captive population from which an escapee could have originated? This was much discussed. Kevin Calhoon is a member of the zoo and aquarium professional community, so he took the lead on researching this. What he found was that the captive population is very small and tightly controlled. The small number of birds that went to private collections are generally pinioned. There had been concern about the birds in Idaho that "disappeared" from a private collection several years ago. It appears that these birds were not actually known to have escaped, and they are known to have been pinioned (which is permanent) so could not have been the source of the intact, free-flying bird in Tennessee. There were no other indications of any other missing birds or potential sources for unaccounted free-flying escapes. No strong basis for reasonable doubt shows up here.

Second, does the wild population have a history of long-distance vagrancy sufficient to get a bird across the Bering Strait and into North America? The answer to this is a definite "yes." There are vagrant records over 1000 miles outside of the usual breeding and wintering ranges in Asia, and by one account as far as in European Russia. The distance from the breeding grounds to the Alaskan mainland is not much greater than this, and the Siberian region the bird would have crossed is almost entirely devoid of birders. It is also worth remembering that Sandhill Cranes have strayed to Great Britain and continental Europe, a distance and direction similar to that required to get a Hooded Crane to North America. Even if this vagrant scenario seems unlikely, the wild population is about 100 times larger than the captive population, and is free-flying and unrestrained. So adjust the improbability factors in accord with this, and see how they feel. Again, I find no basis for reasonable doubt here either.

But, this scenario only gets the bird to Alaska in the company of Lesser Sandhill Cranes. Is it feasible for the bird to then get thousands of miles farther east, most of the way across the continent, and in the company of Greater Sandhills? I would think it certainly is. We have something of an analogue in the Common Crane, a more frequent vagrant to North America. Common Cranes believed to be wild birds from Siberia have made it east to Indiana and Quebec, putting them in the same Greater Sandhill population that winters in Tennessee. If the Nebraska bird was the same individual as the Tennessee Bird, then it would have had the entire summer to wander in the far north, unmated and not tied to any nesting territory. It very easily could have continued its eastern drift and wound up with the eastern Sandhills, then migrated south with them. So, if a bird can get to Alaska in summer, then it is not at all unreasonable that it could wind up in Tennessee in winter, especially if it has been in North America for a year or two already.

The final two-part question is, do the circumstances and behavior of the bird agree with what would be expected from a wild bird, and are they at odds with what might be expected from a captive? Again, I believe the answer is yes and yes. The bird in Tennessee was with migratory Sandhill Cranes, and when spring came it migrated north with them, being seen briefly in Indiana. The same was true in Nebraska the previous spring, when possibly the same bird was see with migrating Sandhills. This is precisely how we would expect a wild Hooded Crane to behave. But do we know that an escaped captive would not do the exact same thing?

We don't know for sure, but there is another Common Crane analogue that I found informative. This is the case of "Ol' Crooked Toe," a captive Common Crane that escaped from captivity in New York in 1993. So far as I know, this is the best-documented situation in which a known captive exotic crane escaped and "went native," being seen repeatedly in the wild in the company of wild Sandhills. His tale is recounted here:

http://www.njaudubon.org/Portals/10/Research/PDF/NJBSpring09.pdf

This bird had a distinctive but non-crippling injury to one toe, allowing it to be identified definitively. In all its years in the wild, it traveled all the way from New York to New Jersey, where it settled down, attracted some wild Sandhills to join in, and raised a flock of non-migratory hybrid offspring that probably remain in the same area to this day. The things I find most relevant about Ol' Crooked Toe is that it did not wander vast distances across the continent, it did not take up with migratory Sandhills, it did not turn up in the staging grounds for the wild cranes. It stayed close to home, found a suitable spot, and settled down. The wild Sandhills joined it, not vice versa.

Given all of this, I felt that the question of wildness was settled for me "beyond a reasonable doubt." Every aspect of the circumstances of this bird was exactly what would be expected if the bird were wild, and there was no contrary evidence, direct or circumstantial, and no apparent likely source for an escapee. I found this an interesting comparison to another recent split decision for our BRC where I was in the 4-2 minority voting to reject a bird because of doubts of wild origin, in spite of strong and vigorous arguments from other committee members who felt otherwise. Tennessee only allows one dissenting vote, so the two negative votes in that case overrode the majority and rejected the record. That time the circumstances left me with what I judged to be reasonable doubts; it was not definitive, but I was uncomfortable setting my doubts aside and I felt I must vote to "leave it out." In the case of the Hooded Crane my initial strong knee-jerk doubts were assuaged by the actual evidence.

I am only speaking for myself here, of course. Other members of the committee are free to discuss their votes or not; I will say that the rationales of the others who voted to accept were in general not radically different from my own. We also knew going in to this that no matter how we decided, there would be hundreds or thousands of people who would think we were wrong!

Friday, December 21, 2012

Hail the New, ye Lads and Lasses!

The new cycle dawned crisp, cold, and free of apocalypse.
Happy Long Count 13.0.0.0.0, the dawn of the 14th b'ak'tun!

Thursday, December 20, 2012

Fast Away the Old B'ak'tun Passes!

Today's Long Count date in Mayan numerals. That reads 12.19.19.17.19, the final day of the 13th B'ak'tun.

Thursday, December 29, 2011

Hooded Crane Origins

Where did the Tennessee Hooded Crane come from?

Apparently this is much on the minds of the North American birding community. Through yesterday there had been 922 visitor-days tallied on the sign-in sheet at the observation platform at Hiwassee NWR since the crane first arrived in mid-December; these visitors have come from 38 states and several foreign countries. My wife and I stopped by on our way to Atlanta a few days ago and were rewarded with leisurely views of our state's current celebrity V.I.B. Opinions vary quite a bit as to what the source of this bird might be; one youtube video appears to suggest that he or she came from Planet Claire.

My initial knee-jerk reaction on hearing of the bird was "that's gotta be an escapee." But as I have learned more, I have shifted from this starting point. There are two critical questions:

1. Is it there a reasonable scenario under which a wild Hooded Crane would arrive in Tennessee without human assistance?

2. Is there a plausible source for an escapee?

My feeling is that if the answer to (1) is yes and (2) is no, then my vote for the bird (I am on the Tennessee Bird Records Committee) is "accept;" otherwise it is "reject." I am still very much in exploratory, open-minded mode about this. But here are some of the most interesting things I have come across:

Much was made of the escape of three Hooded Cranes in Idaho a few years back (date appears to be uncertain). However, it seems fairly certain now that these birds were pinioned and thus could not be the source of either the Tennessee or Nebraska birds in 2011.

The total zoo population of Hooded Cranes worldwide is very small (I have seen the number given as 84), and no escapes are known. The number and status of birds in private collections I have not seen so much about, but there are not going to be many. As I saw it described, "The Hooded Crane is a rare and valuable species and usually in a very secure setting." This means banded and probably pinioned.

There have been long-distance vagrant Hooded Cranes seen in Asia. There are records from Kazakhstan and eastern India, both at least 1000 miles from the usual breeding and wintering areas. If you go only slightly farther to the northeast rather than west, you are in mainland Alaska, and certainly in potential contact with U.S.-wintering Sandhill Cranes.

John Vanderpoel, in a recent blog post, describes the movements of a family group consisting of a Sandhill Crane, a Common Crane, and hybrid offspring. He says that they were Siberian nesters that were seen in the Jasper/Pulaski refuge in Indiana, the Yukon Delta (headed west), and Nebraska. If he has the facts correct, this would seem to make the "wild Hooded Crane comes to Tennessee" scenario very plausible. Many people have doubted whether a wild Hooded Crane could make contact with the Sandhills that winter in Tennessee. Considering that many of the Hiwassee cranes also pass through Jasper/Pulaski, it's only a couple of small steps from the travels of this wild CommonHill Crane family to plop a wild Hooded Crane at Hiwassee (and Nebraska last spring). Remember that this is not a Sandhill Crane and it will not necessarily be tied to the traditional migratory patterns of the Sandhills. It is also an unmated bird, which has a long summer to wander solo in the north.

In recent years there have been Common, Hooded, and Demoiselle Cranes found in the U.S. in the company of flocks of migratory Sandhill Cranes. If these are all escapes, why are they all species that nest in central and eastern Asia, with none of the African or Australian species (some of which are also common in captivity)?

As I said, I remain in investigative mode and am a good ways from casting a BRC vote, both intellectually and temporally. The evidence at this point is definitely trending towards "wild" in my mind; but that could change. Additional information, especially about captives, would be extremely welcome.

ADDENDUM

I've been looking in to the Common Crane scenario more, and here is what I have found in back issues of North American Birds (it is more complicated than what Vanderpoel wrote). If anyone has corrections or expansions to this info, by all means let me know:

Fall 1998: Alaska's first Common Crane in 40 years is found in Delta Junction in a (Lesser) Sandhill staging area. This is southeastern Interior AK, far from the Yukon Delta or Siberia.

Spring 1999: Common Crane at Kearney Nebraska invites speculation because it "shared the pale plumage worn by [the] bird found last fall in Delta Junction." Bird in the company of Sandhills, mostly arctic-nesting Lessers.

Fall 1999: Common Crane mania in Quebec. One adult associating with a Sandhill and two juveniles of possibly hybrid characters. Meanwhile elsewhere in the province, two 1-year old Common/Sandhill hybrids found. This is Greater Sandhill territory, though the subspecies of the Sandhill mate was not determined. Speculation that the adult might be the same bird seen several years previous on the Atlantic coast of the U.S. and determined to be an escapee of known origin, along with two years' worth of its hybrid offspring. No connection presumed between this bird and any wild birds from western North America. Later, though, this escapee was found to be happily resident and reproducing in New Jersey and not wandering in Quebec (see below, Winter 2000-2001)

Fall 1999: About a month later, a Common Crane appears at Jasper-Pulaski in Indiana, the major staging ground for Greater Sandhills. The bird is in the company of an adult Sandhill and two juvenile hybrids. Initially believed to be the same as the Quebec bird, but then the adult Sandhill was determined to be a LESSER Sandhill. Suspicion then turns towards its possibly being the same bird seen in Nebraska in the spring. Birders farther south eagerly await the arrival of the Common Crane with the migrating Sandhills; however it is not seen.

Spring 2000: A Common Crane appears in Nebraska in the company of a Lesser Sandhill Crane and two apparent hybrid youngsters. Could the Indiana family have found its way back to Nebraska???

Winter 2000-2001: An SA report in the Hudson-Delaware region details that there is a small resident population of Sandhills, the original escapee Common Crane, and numerous hybrid offspring in New Jersey. So this escaped bird does not account for the Quebec or Indiana birds.

Of course it is not definite that ANY of these birds were the same individual, or than ANY of the eastern birds were wild (western birds are generally presumed wild). One thing it does make clear, though, is that some Lesser Sandhills do reach Jasper-Pulaski. The similarity to the sequence of the three recent Hooded Crane occurrences (ID spring 2010, NE spring 2011, TN fall 2011) is interesting. It does appear to suggest that a wild Common Crane made it over from Siberia, paired up with a Lesser Sandhill, and travelled to Indiana (and presumably farther south, as it disappeared from Indiana in November).

Wednesday, December 14, 2011

Hooded Crane in Tennessee

I'm sure this news is buzzing through the birdosphere already!

An adult Hooded Crane was found today among the wintering Sandhill Cranes at Hiwassee National Wildlife Refuge in east Tennessee. For those unfamiliar with the species, this is a bird of southeastern Siberia and elsewhere in the far east. It is endangered in the wild, and also kept in captivity in North America. Amazingly, this is the THIRD Hooded Crane sighting in the U.S. in recent years, after one in Idaho in 2010 and one in Nebraska in April of this year. Discussion will doubtless continue for a long time about the possibilities for wild versus escaped origin, the odds that the Tennessee bird could be the same as the Nebraska and/or Idaho birds, etc. But whatever its origins, this is a rare and beautiful sight, bringing the total of crane species currently residing at Hiwassee to three (though only one is presently ABA-countable).

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