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.


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).


At 5:42 PM, Blogger cyberthrush said...

Bill, I've conjectured to some the (farfetched???) possibility that 2 of those escapees from 5 yrs. ago could've found each other, bred, and produced your TN. bird as a wild offspring...
On the other hand, it's still not clear to me if there is any 'underground' market for this species, and unlicensed holding facilities around, who wouldn't admit to losing a bird even if they did... possibly not investigatable?

At 8:28 AM, Blogger Bill Pulliam said...

I am not sure that those Idaho birds are known to have actually "escaped" rather than just having "disappeared." I would think the survival prospects of a pinioned crane in the wild are not great, and the prospects for successfully raising young seem even bleaker without protection, support, and feeding from human attendants.

As for the private market, legit and underground, there are ALWAYS people who know about those things. Nebraska and Tennessee folks are investigating these possibilities. A black market Hooded Crane would be a really expensive beast, one you would likely take great care not to lose!

At 9:56 AM, Blogger Jim said...

Couldn't find an e-mail/contact for you Bill.

Where is "Hiwassee NWR" and would it be worth visiting in February.

We are bird photographers more than birders


Jim Robertson

At 11:52 AM, Blogger cyberthrush said...

I suspect you'll have your own blog update soon Bill, but until then your readers will probably be interested to read Ned Brinkley's recent take on things here (with a lot of new info):

At 1:47 PM, Blogger Bill Pulliam said...

Cy -- thanks for posting the link. I just saw that this morning and was thinking about linking to it. It seems the case for a captive origin is growing steadily weaker.

The Hooded Crane record hasn't even been officially circulated to the Tennessee BRC yet. But I would say to any listers who have not chased this bird because they doubt that they will ever be able to count it under ABA rules: Don't be so sure about that!

At 8:13 PM, Anonymous Michael Retter said...

The Idaho escapees were all females, according to what I've read, so that would make their producing offspring amongst themselves rather miraculous!


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