18 June 2014

Vultur sacra an Invalid Taxon

The "Vultur sacra" as an Invalid Taxon and Shortcomings in the Veracity of Bartram's "Travels"

By Mathew Lewis, June 17, 2014. Contributed in reply to: “Painted Vulture a Former American Species

William Bartram described an unusual form of vulture from the St. Johns River in Florida, the existence of which has since been a mystery. Bartram gave it the name "Vultur sacra." Many authors have rejected the idea that this description represents either a species or subspecies distinct from the King Vulture (Vultur [=Sarcorhamphus] papa), and those authors' position I support and reinforce, but, in part, my opinions are from a different angle.

I conclude that "Vultur sacra" is probably a mythical entity, a nomina dubia and composite impression of two valid species, and that Bartram probably never saw a Sarcorhamphus vulture in Florida at all. Instead, he observed, but probably did not collect, an example of a juvenile Caracara (Caracara cheriway); if "sacra" deserves any placement, it should be assigned as a synonym of that species. My views are largely in line with Allen (‘Bull. Mus. Harvard’ 2: 313-316), but with some disagreement. In rejection of "sacra" I present an explanation that explains the genesis of the matter and how that, in the very least, undermines the integrity and veracity of Bartram's writing in 'Travels...'

The "discussion" refers to a general overview of the debate, with emphasis on 'Travels...' and the reports of Harper ('Auk,' 53:381--392), Snyder & Fry ('Zootaxa,' 3613(1): 61-82), Burns ('Wilson Bulletin,' 20: 136-8 (1908)), and Brown & Amadon ('Eagles, Hawks and Falcons of the World;' 1: 182, 2: 858), as well as other works cited below. The discussion includes my explanations and arguments.

Lack of Comparative Analysis

Discussion does not include how Eleazar Albin did not make comparative analysis of the bird he described, that Albin described a single individual and with no establishment of understanding a second, separate taxonomic concept.

[Bartram's work employs usage and familiarity with Linnaean and scientific names throughout ("Vultur aurea" [sic] appears same page), but in creating "sacra" he does not explicitly distinguish it from Vultur papa Linnaeus, 1758.

This might suggest that “Vultur sacra” is a nomina nova -- and essentially that a sole taxonomic concept of Sarcorhamphus is not being compromised. However, further points I make below demonstrate that Bartram in ‘Travels...’ (1791) WAS distinguishing “sacra” from Vultur papa -— but only as a matter of his confusing the King with his earlier observation (circa 1773—1774) of the Caracara. Though this distinction can be inferred from ‘Travels...,’ in no way does it validate “sacra”.

Albin's Illustration is not Relevant to Bartram

Discussion does not account for possibility of a misidentified King Vulture in Albin (white undertail coverts concealing relatively short undertail accounting for "diagnostic" features of "sacra"), and it is too coincidental that the tail color and pattern ascribed to "sacra" is its only diagnostic feature when such feature in the King is one prone to be misconstrued, which likewise the discussion does not rectify.

In employing "tail" Eleazar Albin may have actually meant to incorporate, by contextual definition therein, the white undertail-coverts, which can by impression layer the basal part of the undertail itself (see image under "Description" https://beautyofbirds.com/americankingvultures.html and see Harrison and Greensmith ('Birds of the World,' Dorling Kindersley: 88). Feathers of the undertail coverts can almost completely conceal the tail--which may be of a different color--in other bird species (i.e., Mycteria americana).

In arguing for "sacra" Snyder & Fry ('Zootaxa,' 3613(1): 61-82) correlate Albin's bird to Bartram's words. Their rationale is that the basal white part of Albin's tail represents something distinct from a uniformly black-tailed King Vulture, and they account for the discrepancy in the amounts of white in Albin's and Bartram's descriptions as "intraspecific variation." Albin's illustration is a vulture depicted in frontal view, and my point in the above paragraph is not reconciled by Snyder & Fry. Further, and more compelling, they do not reconcile how Albin's is not the only book illustration to similarly and closely depict a King Vulture with extensive white undertail-coverts (Meyer de Schauensee, 'Birds of Colombia': 45). Thus, the "diagnostic" feature is not unique to hypothetical Florida vultures. Further review of the literature (book illustrations) might indiscriminately reveal more examples of Kings with extensive white undertail-coverts.

Linnaeus and others are correct to place reference to Albin in synonymy of the King. Provenance of Albin's vulture would not likely have been Florida but a colony where the British traded or had a presence.

Feathers represented in portrait of Micco Chlucco from 'Travels' do not show diagnostic features. The original portrait, as presented in 'William Bartram, the Search...' (Hallock & Hoffmann, eds., Univ. Georgia Press (2010): 151), shows feathers which evidently have a three-part pattern, although this portrait is not colored. As Harper (382-383) notes, Bartram indicated (‘Travels...’ 151-152, 454) that the feathers are ““painted with a zone of red within the brown tips...”” The feathers in the portrait are therefore consistent with examples of tail feathers of an immature or second-year Bald Eagle (Haliaaetus leucocephalus), and question of the three-part pattern is reconciled. Given that its tail is barred, the Caracara would not account for the feathers figured in the portrait. It is the Bald Eagle’s feathers which are, typically, of ceremonial use by native American tribes.

A limestone bowl from Alabama (Snyder & Fry) does not show diagnostic features but is intriguing as to the possibility of one or more native tribes in the southeastern United States, at some unknown point, being familiar with the King. [Discussion excludes examination of hypothetical records or potentiality of the King occurring north of Mexico, but the Arizona case is cited in reinforcing my arguments].

Bartram Probably Did Not Collect a Type

Difficult to accept whether Bartram actually collected a specimen as mentioned in manuscript (may not have acted on "oppertunity [sic] of getting one" in Harper (389), from ms.), and more compelling, this point is omitted in his 'Travels,' as well as how no known example of this vulture is represented from his animal drawings and how his manuscript makes no reference at all to the tail.

I dispute Harper’s assertion (also reinforced in Snyder & Fry) that “there is no longer any question as to whether Bartram had a specimen in hand, and this utterly disposes of any further possibility of referring to his bird as a “mythical species.”” Rather, I feel that Bartram in his letter to Fothergill was implying that the birds he observed were to be expected in the St. Johns River basin. Friedmann (‘Birds of North and Middle America...,’ 11: 602) explicitly names the St. Johns as a distributional locality of the resident Caracara. Further arguments below underscore this point, and Bartram was probably working from memory in ‘Travels...’

Lack of Explanation for Its Presumed Extinction

Discussion does not explain cause of extinction in presumed "sacra." Bartram's manuscript alludes to these vultures occurring in "flocks" but gregariousness is not typical of the King, a species whose recent distributional contraction is greatly a consequence of its limited sociality, and if "sacra" was a more sociable vulture the argument for an expedient extinction is difficult to fathom.

Acceptance of "Sacra" in Literature Without Merit

The acceptance of "sacra" in 19th century works is in historic context another facet of natural history writing, and those references (Cassin’s works) do nothing to reinforce the presumed validity of it, but rather they illustrate how authors so readily perpetuated what their forbears wrote (see Harper (390) on the "pedes rubri" ascribed to the King in Buffon and Linnaeus’ twelfth edition).

Discussion gives legitimacy to the sincerity of Albin and mandates some legitimacy to the sincerity of Bartram, but does not account for the former and likelihood of the latter presenting imprecise statements which in context cannot be taken literally. In hand with cases where any preserved evidence is deficient or nonexistent, this much is also a facet of natural history writing (see Nuttall in his liberties in describing tail of "sacra," 'Manual of Ornithology' 1: 42).

John Cassin originally referred to "sacra" as "doubtful," though without explanation validly used it later (Cassin, 'United States Exploring Expedition' and 'Illustrations of the Birds of California...').

Bartram Originally Described a Juvenile Caracara

Bartram wrote a letter to John Fothergill which was not published until Harper's review in 1936 (389). The letter refers to his period in the St. Johns area, circa 1773—1774. Harper and others following ascribed Bartram’s description of a “Croped Vulture” to a Sarcorhamphus vulture. What is being described as the “Croped Vulture” is the Caracara.

““The Croped Vulture. This is a very beautiful bird, not quite so large as the Turkey buzard, they are chiefly white the back & wings of a deep nut brown, the Bill yellow Legs white, the head & part of the neck bare of feathers covered with a naked skin of a vermillion colour, what is remarkeble sic in the Bird their craw or stomack hangs like a pouch or purse bearing outside on the breast & bare of feathers. When the vast meadows and Savanahs of Florida are set on fire, they gather in flocks to the new burnt ground where they feed on the roasted snake frogs Lizards Turapins and other reptiles, where I had an oppertunity of getting one. ””

At first glance, a superficial impression of a Sarcorhamphus vulture can be construed from this, and Harper no doubt was given to believe it, writing that the description “agrees somewhat better with the King Vulture than does the one in the ‘Travels.’” Harper is in my view writing from a confirmation bias in his assertion, and Bartram’s words actually follow a description of a Caracara closely.

It is “not quite so large as the Turkey buzard [sic],..” Measurements [cm.] from Howell & Webb (‘Guide to the Birds of Mexico and Northern..’ (Oxford, 1995)) allow fair comparison of the averages of all three species, and Bartram’s estimation is appropriate if he observed the smallest of these.

Caracara: 48-58.5; WS (wingspan) 115-132
Turkey Vulture: 66-76.5, WS 165-183
King Vulture: 71-81.5, WS 176-193

In ‘Travels...,’ the “Painted Vulture” is “near the size” of the Turkey Vulture (Cathartes aura), and its “wings are much shorter” to such a degree that it “falls greatly below that admirable bird in sail.” No measurements of “sacra” were ever made.

The back and wings of the Caracara are "nut brown," particularly in younger birds, where in the adult King (juveniles dark blackish brown gradually assuming the white pattern) they are black or intensely dark approaching blackish. So "nut brown" is too light a pigment to permit this comparison. The phrase “chiefly white” is also a fair appreciation of the white or pale cream areas of the Caracara’s neck and underparts.

In adult Carcaras the tarsi and feet are yellow, but in the juveniles they are very pale/grayish-white, with at best a yellow tinge (ill. Brown & Amadon, 2: 733). The beak of the Caracara is bluish in tone, but can also appear a translucent whitish--especially when seen from a distance. Clark & Wheeler (‘Hawks,” 92) describe it as “horn-colored.” [It is also worth noting that Bartram’s description may have reversed the color of the beak and tarsi, if his observation had been an adult, and that the natural beak color of the Caracara is difficult to precisely or reliably ascribe to color, so that “white” or “yellow” might either be interpreted, and though recent authors tend to use “blue,” above reference to Clark & Wheeler shows, among others, how this character is open to varied interpretation].

Harper and others following are likewise confused on the head and neck characters, which actually hold in the Caracara. The King Vulture’s beak is orange with black at the base, and its legs are white. It also forces the question as to why Bartram would omit reference to the other prominent colors and features of the King's head and neck. The “vermillion” [sic] is a correct impression of the bare skin of the Caracara, though Harper interprets Bartram as only suggesting that the entire head is "bare of feathers," which I believe is not what he meant in an absolute sense.

Both the Caracara and the King Vulture possess a crop which swells when feeding, and writers on this point ignore this in the former. Allen (‘Bull. Mus. Harvard’ 2: 313-316) outright disputes the existence of a swollen crop in American birds.

The descriptions from Bartram might suggest the possibility of the existence of a unique Sarcorhamphus, distinct from the King and smaller than that species and the Turkey Vulture. However, this does not reconcile the description of a juvenile Caracara.

Further compelling, Bartram’s ‘Travels..’ omits reference to beak color. The “red” parts apply to the bare skin of the neck and crown, but more specific terms applied include “redish-orange” [sic] and “coral red,” with no reference to the intense vermilion hue of the Croped.

There is also the important question of the tail, which is only cited in ‘Travels...’ (see below for discussion).

Bartram's Bird not an American Vulture in Behavior

Bartram in ‘Travels..’ and in his letter to Fothergill describes a bird which is an opportunist and gregarious. This is true for vultures in general and American vultures of the Cathartidae. Bartram’s letter mentions that they appear in “flocks,” but by ‘Travels...’ that is embellished, and the birds now appear “from every quarter.” As noted above, the King is usually solitary and not gregarious, often appearing in pairs, with sometimes a juvenile in company (‘Handbook of the Birds...’ (Lynx Edicions), vol. 2). Yet even if I were to attribute a remarkably different type of behavior in a hypothetical Sarcorhamphus distinct from the King, what Bartram describes, specifically, is probably not to be observed in cathartid vultures.

Bartram in describing how the birds in ‘Travels...’ “alight upon the ground” and in his letter where they “gather in flocks to the new burnt ground” is describing behavior that BEST applies to the Caracara, which is an opportunist, and cursorial in feeding habits, it favors reptiles, especially lizards. These are captured in its feet, and with its claws the Caracara can either lift or hold down its prey.

The Caracara [Falconidae, Polyborinae] and other raptors (sequence of Brown & Amadon) are quite removed from the American vultures, which are by homology close to storks (Ciconiidae) in relationship. Important for the discussion is their possessing a prolonged basal phalanx in the second toe, and this prevents them from clutching or gripping. Thus, Harper quoting from Bartram (382) that they “gather up” reptiles, implies either lifting or manipulation by use of the toes, which would not occur in cathartid vultures.

Veracity of Bartram Compromised in "Travels..."

Most compelling to the arguments is the question of the veracity of Bartram’s published ‘Travels...’ This does not hold for what he wrote to Fothergill that is quoted in Harper. Harper explains that Bartram did not have complete oversight of the publication of his work, the process of turning his ms. into the 'Travels,' and he had wanted to revise his edition; the book “had not been published under his own inspection (389, f.).” Further examination of the the description of “sacra” in ‘Travels...’ allows credence to this comment.

The description of “sacra” in ‘Travels...’ is taken from Bartram’s original impressions, including his letter or manuscript. Harper (389, f.) notes from the letter of William Baldwin that “...he had by him all his original manuscripts.” Presumably, these were not preserved by the time of Harper and are here treated as distinct from his correspondence to Fothergill. Yet, I believe that what descriptive characters of the “Croped Vulture” that are not mentioned from these “originals”—making such description seem incomplete—were heavily supplemented by the description of characters of the King Vulture in a work which must have been familiar to Bartram or the person who oversaw publication of ‘Travels...’ That work is ‘A Natural History of Uncommon Birds, ...’ ((Edwards (1743), 1:2, plate [II]), “The King of the Vultures”).

Essentially, George Edwards is liberally paraphrased in ‘Travels...’ --

****BARTRAM [in Harper]: “The bill is long and straight almost to the point, when it is hooked or bent suddenly down and sharp;..”
EDWARDS: “The Bill is pretty thick and strong, straight for a little way, then bends into a Hook, and over-hangs the lower Mandible;”
****BARTRAM: “[feathers] become long and of a soft texture, forming a ruff or tippet, in which the bird by contracting his neck can hide that as well as his head..”
EDWARDS: “at the bottom of the Neck, a Ruff of loose, soft, ash-colour’d Feathers, quite round, in which, by Contraction, it can hide its whole Neck and Sides of the Head;...”
****BARTRAM: “the bare skin on the neck appears loose and wrinkled, which is of a deep bright yellow colour, intermixed with coral red; the hinder part of the neck is nearly covered with short, stiff hair; and the skin of this part of the neck is of a dun-purple colour, gradually becoming red...The crown of head is red;..”
EDWARDS: “the Head and Neck are cover’d with bare Skin; the Crown of a dirty, Flesh-colour, toward the Bill, and Scarlet in the hinder Part, behind which is a little Tuft of black Hairs: From this Tuft proceeds, on each side, and parts the Head from the Neck, a sort of Stay of wrinkled Skin, of a brownish Colour, with a little Blue and Red in its hinder Part:”
****BARTRAM: “there are lobed lappets of a redish orange colour, which lay on the base of the upper mandible.”
EDWARDS: “[Mandibles] cover’d with a Skin of an orange Colour, broad, and pointing to the Crown of the Head, on each Side above, in which Spaces are placed the Nostrils, of an oblong Shape: Between the Nostrils is a loose flap of Skin, scolloped, which falls indifferently on either Side of the Bill,”
****BARTRAM: “the quill feathers of the wings and two or three rows of the coverts, which are of a beautiful dark brown;”
EDWARDS: “the Quill-feathers of the Wings, black;...the Row of Coverts, next above the Quills, is black”
****BARTRAM: “the legs and feet of a clear white;”
EDWARDS: “the Legs and Feet are of a dirty [EMPHASIS MINE], white Colour;”

This indeed gives special meaning to “paraphrase” in how the separate, respective descriptions are presented, and it is not coincidence. As noted, Bartram likely did not have oversight of publication of ‘Travels..,’ and thus he cannot be considered truly culpable. YET IN THE EXCESSIVE PARAPHASING OF EDWARDS TO ACCOUNT FOR THE INADEQUATE POINTS OF DESCRIPTION OF THE “CROPED”/”PAINTED” VULTURE, THE INTEGRITY AND VERACITY OF BARTRAM’S PUBLISHED WORK ARE COMPROMISED. LIKEWISE, THIS POINT UNDERMINES ARGUMENTS BY PROPONENTS OF THE VALIDITY OF “SACRA.”

What I believe represents a sequence as explanation is that Bartram presented his ms. to his “copy editor” (body who oversaw publication and presentation of ‘Travels..’), and this editor may have drawn comparison of Bartram’s original description (from those prior observations 16—18 years before) to the King Vulture as described and figured in Edwards (of whom this editor was familiar). FROM ‘TRAVELS...’ I INFER A COMPOSITE IMPRESSION OF BOTH THE KING AND THE CARACARA. Perhaps this editor, or even possibly Bartram, sincerely believed that the bird in question was a King, and no small parsimony was taken in attributing colors and features of the King to the bird that Bartram observed, when nothing of the sort was ever discerned in the original bird. I presume that Bartram, not his editor, was the only explorer to the St. Johns basin (his editor not being familiar with either bird species).

Comparing the description by Bartram in his letter to Fothergill to what was published in ‘Travels...,’ if such comparison is justified as an indication of how Bartram’s original ideas were conserved, does reveal that the characters of the “Croped” were actually retained in the later book, however the omission of the color of beak. ‘Travels...’ does include description of the crop and comparison of size to the Turkey Vulture, and neither points appear in Edwards, as the King is the larger anyhow.

There is the question of tail color. From Edwards, further rectification of the matter is suggested: “covert Feathers under the Tail are White, ...the Rump and upper covert Feathers of the Tail are White; ...the Tail is wholly black; tho’ Mr. Albin makes it black only at the End;”

From this, it is obvious that Bartram or his editor took their “sacra” to have “the tail which is large and white is tipped with this dark brown or black;..” This, not unlike Snyder & Fry, being a motivation from Edwards’ reference to Albin, the latter of whom they also mimic, but also AT ONCE, due to CONFUSION with the Caracara, a consequence of Bartram’s recollection. THE POSSIBILITY OF THE EXISTENCE OF THE MS. FOR ‘TRAVELS...’ IN BARTRAM’S HAND ALONE WOULD LIKELY INCLUDE REFERENCE TO TAIL, (AMONG OTHER POINTS) DESPITE NO REFERENCE OF THAT CHARACTER IN HIS EARLIER LETTER. WITH NO TYPE, BARTRAM PREPARED THE MS. DESCRIPTION OF “SACRA” FROM RECOLLECTION.

‘Travels..’ notes that the iris is “gold coloured,” but in Edwards the “Iris of the Eye is of a bright, pearly Whiteness;...” This point from Bartram is likely a genuine recollection of the Caracara, which has that part a light brown to weak gold color. See Pictures 3-4, http://www.animalspot.net/crested-caracara.html (Plate in Brown & Amadon has it an uncharacteristic reddish or russet).

For the humble Caracara to be described with features and colors of the more exotic King presents another possible argument as to the motivation of an inaccurate description, that ‘Travels...’ would be all the more a publisher’s success. Given the international acclaim of the work, which was translated, this is worth note, yet it is not clear if or to what degree Bartram himself was involved.

Bartram's veracity is also criticized in Burns ('Wilson Bulletin,' 20: 136-8 (1908)).

Bartram Was Not Familiar With Caracara in the Literature

An understanding of the bibliography of the Caracara further explains these arguments. Any reference to the Caracara is conspicuously omitted in Bartram, however the description from his letter, especially with regards to the bird’s behavior. The works consulted in publication of ‘Travels...’ which refer to scientific names or other references make no references to it. THIS IS BECAUSE THE CARACARA, UNLIKE THE KING VULTURE, WAS A RELATIVELY RECENT ADDITION TO THE LITERATURE, AND THIS ADDED TO THE CONFUSION OVER “SACRA.” Having consulted Friedmann (598-599, 602) and Hellmayr & Conover (‘Catalogue of the Birds...,’ part 1/4), I believe that Bartram was not familiar with what he was observing, and very ironically, his letter to Fothergill (however unpublished until 1936 and with no scientific name) is one of the earliest descriptions of the Caracara as a new species.

References from 1777—1790, cited in Friedmann and in Hellmayr & Conover, of names applicable to the genus Caracara [Polyborus] (Falco plancus, Falco tharus, “Falco brasiliensis,” Falco cheriway) are from the following: Miller [Cimelia Physica (1777)]; Molina [Stagg. Stor. Nat. del Chili (1782)]; Jacquinot [Beitrage zur Geschichte der Vogel (1784)]; Gmelin (Linnaeus) [Systema Naturae, ed. XIII, part I (1788)]; and Latham [Index Orn. (1790)]. Brisson [‘Ornithologie,’ I: 405 (1760)] described “Le Busard du Bresil.” Brown [‘Ill. Zool.,’ (1766)] described the “Tawny Vulture” from the Falkland Islands (Sharpe, ‘Catalogue of the Birds in the British Museum,’ I: 31).

Miller (1777) provides the earliest scientific name for any taxons in the genus, Falco plancus. All of the above names are from works which were probably too obscure for Bartram (or editor) to have been familiar by the year 1791, or these references, applying to South American examples of Caracara plancus, would likely have been overlooked even if those works were consulted.

The earliest explicit reference to the Caracara in Florida (and north of present-day Mexico) is the “Polyborus vulgaris” of Audubon, ‘Birds of America,’ part II, folio pl. 161 (1834). [The dubious name “Aquila maculosa” Vieillot, 1807 has also been included in synonymy of Caracara, but Sharpe (I: 62) places it elsewhere.]

Misidentified Caracara Likely Confused Elsewhere in Literature

Coues (‘Bull. Nuttall Orn. Club’ VI: 248) refers to his claimed observation of the King in Arizona Territory in 1865. Coues further discloses therein the claim by Willard Rice who circa 1881 collected “a pair” along the Verde River which “had a nest in a large cotton-wood tree.” This type of breeding behavior, as Coues makes point, would not be possible in the King Vulture, which, as noted, has a foot structure that prevents it from nest construction. I suggest that Rice collected a pair of Caracaras. This does not address the Coues’ sighting (‘Proc. Philadelphia Academy,’ 1866: 49), which though considered hypothetical as a record does have some legitimacy, as Coues was familiar with both species. The claim by Rice nonetheless is a possible example, however unusual, of both species having history of being confused together.

In conclusion, William Bartram probably wrote in his letter to Fothergill a description of an OBSERVED juvenile Caracara. Unfamiliar with the identity and scientific name of the Caracara in the literature, a putative form of bird was created in ‘Travels...’ to account for features not mentioned in Bartram’s manuscript for that work. The genesis of the mistake was due to his not having a type and how, easily for Bartram and readily for his interpreters, the characters of both species also at once became CONFUSED.

The form of bird called “sacra” in Bartram’s book is a vulture similar to the King, as the Caracara has strong semblance to it, and though the identity of the author or editor who wrote that description is not clear (Bartram not having complete oversight of publication), the description was largely the product of heavy paraphrasing from Edwards (1743). Nonetheless, ‘Travels...’ cannot be construed as a work reliable in its veracity, and proponents of the validity of “sacra” do not have argument in it.

Bartram (or the hand by which his 'Travels' was edited) took aims to paraphrase the description of the King in Edwards, but since his own recollections did most certainly recall rectrices which identify with the Caracara, he decided to preserve that point without fully articulating his move.

Ultimately, it is untenable that the name “Vultur sacra” is invalid. The concept behind it, a unique species or subspecies of Sarcorhamphus vulture in the Florida peninsula, has not been substantiated. This is because this type of bird likely did not exist. The Caracara (Caracara cheriway) accounts for the original observation, as well as all the confusion and flaws, and contra Allen, I think that “sacra,” if as a name it warrants placement (Bartram’s names being suppressed in the ornithological literature anyhow), should be placed as synonym of it. It is perplexing why Harper and other later authors ignore discrepancies in the separate descriptions in Bartram’s letter and his book.