The Louisiana Egret: More Than Anyone Could Possibly Want to Know, and a Lament

This pretty little Tricolored Heron juvenile has been one of the stars of the show at Dekorte Park recently. Still common enough twenty years ago in New Jersey’s southern marshes, the species is declining rapidly in the state; Bill Boyle’s fine new S&D book reports barely three dozen birds in five colonies in 2009, while just ten years earlier Walsh et al. could still call it “fairly common” and “increasing” after its arrival as a breeding bird in 1948. In spite of this elegant bird’s propensity to show up, and even to nest, far north and inland of its usual breeding range, it’s never been anything but rare away from the coast in New Jersey, and this one has no doubt enriched many a Bergen County list since it arrived ten days ago.

The taxonomy of the herons, tiger-herons, bitterns, boat-bills, and night-herons seems to have settled down in the past couple of decades; it’s a good thing, too, given that, as Frederick Sheldon has noted,

over the last 100 years, the number of recognized species in  the Ardeidae has varied  from  60 to 93 and the number of  genera from  15 to 35.
That’s a lot of varying, even for an ornithological classification, and those of us who have been birding for more than even a couple of years have had to adjust more than once. “Green-backed Heron,” anyone? No North American heron has undergone as much taxonomic change as the Tricolored Heron, though, which has had two English names and two scientific names just in my lifetime–and more before that. (By the way, go ahead and click on that link; it will take you to a pretty cool resource.) Just about the only combination we haven’t suffered through is the one in the title of this post. But we’ll get there someday, I’m sure.
The onomastic history of this bird starts with a posthumous publication. On January 5, 1776, the professor of (among a wide range of other subjects) natural history at Erlangen, the imposingly named Philipp Ludwig Statius (Statius!) Müller, died, suddenly and “in the best of his years.” Fortunately, Müller had just delivered to his publisher the manuscript of the index and supplement to his German translation and commentary of the twelfth edition of Linnaeus’s Systema, and that volume appeared in Nuremberg not long after the author’s untimely death.
Drawing on recent updates published by Linnaeus and on discoveries reported by the other famous naturalists of the day, Müller’s Supplement offered the first published descriptions of a number of animals, including a heron he calls “der dreyfärbige Reiher. Ardea tricolor.” He describes it briefly:
The bird is blackish-blue, white underneath, and has blue tail coverts. Its range is in America. – Buffon.
Terse as it is, Müller’s description answers one question I’ve heard over and over at Dekorte: what are the heron’s three colors? For years I’d assumed that they were red, white, and blue, the signature palette of the attractive juveniles, but not so: this description is of an adult.
Today, Müller is credited as the “author” of the current scientific name of the heron, Egretta tricolor (Müller). What that means in practice is that he was the first to publish for the species a Latinized binomial formally acceptable under the criteria of the ICZN–but what about that citation at the end of Müller’s description?
Wikimedia Commons

Müller’s description is an abbreviation of this account of “La Demi-Aigrette” in Buffon’s Histoire naturelle des oiseaux:

We have given this name, Demi-Aigrette, to a bluish, white-bellied heron from Cayenne, shown in our Plates; the name designates a characteristic that seems to be intermediate between egrets and herons: unlike the egrets, this species does not have long, airy plumes on the back, but rather only a cluster of sparse strands that extend beyond the tail and represent a smaller version of the tufts of an egret. These strands, which other herons do not have, are reddish in color. This bird is less than two feet in length. The front of the body, the neck, and the head are dusky bluish, and the underparts are white.
Buffon, a sworn enemy of the great Swedish taxonomist, does not assign his heron a Linnaean name. But he does publish a painting of it, and it is this image that provided the type “specimen” for Müller:
The caption in these Planches enluminées gives our bird yet another name: the “bluish heron with a white belly from Cayenne.” The painting itself leaves a lot to be desired as either an aesthetic or a scientific document, but it matches neatly with Buffon’s description, right down to the rusty bustle. Müller’s copy of the plate must have been poorly colored for him to concentrate on the blue tail coverts instead.
Alexander Wilson, the Scots father of American ornithology, was aware of Buffon’s description and of John Latham’s somewhat more thorough account of the Demi Egret when he collected and painted a specimen that would later end up in Peale’s Philadelphia Museum.
Like all of Wilson’s birds, the heron and its platemates are awkwardly drawn to the point of ridiculousness; but this is the oldest painting showing a bird readily identifiable as a Tricolored Heron. Wilson can be forgiven, I think, for not recognizing that his bird and the Cayenne bird of the older descriptions were in fact conspecific: he says that the “Demi Egret … seems to approach near to the present” “rare and delicate” species, which he named, in honor of the place he first found it below New Orleans, the Louisiana Heron, Ardea ludoviciana.
Twenty-five years after Wilson’s publication, his colleague and champion Charles Bonaparte moved the Louisiana Heron into Forster’s genus Egretta. In 1858, Spencer Baird shifted this species, the Reddish Egret, and Peale’s Egret (now known to be the white morph of the Reddish Egret) to Demiegretta, a genus said by Baird to have been coined by Blyth, in obvious reliance on Buffon and Latham, to include the Western Reef-Heron. But Baird is skeptical: he has
a strong suspicion that the American birds, with Ardea ludoviciana as type, are entitled to a new generic appellation, for which Hydranassa would be exceedingly appropriate.
Baird leaves it at that, without bothering to explain why his suggested name would be so fitting. It would remain for Elliott Coues–who else–to unravel the “ornithophilologicality” of Baird’s proposal. Coues points out that the name is not to be analyzed as the bland “hydra” + “nassa” = “water duck,” but rather as the much more poetic “hydra” + “anassa” = “water queen.” And then, in one of those casual displays of memory and erudition to which the great man was given, he identifies Baird’s source in Audubon’s Ornithological Biography:
Delicate in form, beautiful in plumage, and graceful in its movements, I never see this interesting Heron, without calling it the Lady of the Waters.
Audubon’s painting (much of it done by his gifted assistant George Lehman) does the nickname justice, depicting a bird that seems almost to wear the elegant feathers it is so carefully arranging.
Coues’s own 1873 list of North American birds, the immediate forebear of the AOU Check-list, provides one of the clearest examples of the muddiness of this species’ taxonomic history. The Buffonian-Müllerian name is nowhere to be found, but neither is Wilson’s or Baird’s. Instead, Coues calls the lady of the waters “Ardea leucogastra Gm., var. leucoprymna (Licht.) Cs.”
Hypercorrecting for gender (as if “leucogaster” were an adjective rather than a noun in apposition), Coues adopts the name given the species in the Systema naturae of Gmelin’s 1788 edition, Ardea leucogaster. Lichtenstein, professor of zoology in Berlin, had assigned the epithet leucoprymna (with no further published description) to a specimen in his care, a nomen nudum that Coues (the “Cs.” of the full name citation above) re-purposed to designate the subspecies (“variety,” as we called them back before the trinomial controversy was settled the first time) that occurs in the southern United States.
Coues was the head of the committee constituted by the AOU in 1883 to prepare an official checklist of North American birds. When the first edition appeared in 1886, it eschewed Coues’s name for the heron and demoted Baird’s Hydranassa (which Ridgway had flirted with nearly ten years earlier) to a subgenus; for the first time, the Check-list joined Wilson’s English name Louisiana Heron with Müller’s scientific moniker Ardea tricolor. In keeping with the committee’s determination to “amplif[y], increas[e] the effective force of, and len[d] a new precision” to ornithological naming, the Louisiana Herons of the northern part of the species’s range are further defined by the addition of a subspecific epithet, ruficollis, originally the specific name given by Gosse in 1847 when he described a juvenile Tricolored Heron as a new species, the Red-necked Gaulin, Egretta ruficollis.
The name Ardea tricolor stood until 1905, when the Twelfth Supplement to the AOU Check-list elevated almost all of the heron subgenera to genus status. Baird’s suspicion was validated, and Hydranassa lasted for three quarters of a century, until the next revision of the herons was adopted in the thirty-fourth supplement, published in 1982. The Little Blue Heron, the Reddish Egret, and the species under discussion here were all moved (back) into Egretta, a reconstituted genus they shared (and share today) with another ten or so small, slender herons.
That same supplement changed the English name of the old Louisiana Heron to Tricolored Heron, a nod to the range of the bird, which extends far beyond the lower Mississippi, and to its new and old specific epithet. If I’d been asked (I don’t remember getting a call), I would probably have gone all the way and called it the Tricolored Egret (along with Little Blue Egret and so on). But Tricolored Heron it is, and likely long will be.
An egret by any other name–

I for one am sorry to have lost another “Louisiana” bird. I know the arguments against honorific patronyms and geographic designations, and they sometimes seem fairly persuasive, but when I see the bird and call it, as I am still likely to do when I’m feeling tired or perverse, a Louisiana Heron, I think of Wilson and Audubon and Lehman, of the swamps of Charleston and the big woods of the Mississippi Valley. The “new” name, even though it is also an old name, conjures up no visions, no affections or remembrances; it’s logical and sensible, but hardly evocative. And names should evoke, shouldn’t they?

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