“My observations of the Herons during the past season do not correspond with those of Mr. N. B. Moore, as recorded on page 232 of your article[[1]], in regard to their feeding habits. I found them generally living in communities, roosting, nesting, and feeding together, like Pigeons, and often observed flocks of the Little White, Reddish, and other Egrets, feeding together like Teal Ducks. Two specimens of A. occidentalis were seen feeding quietly within twenty feet of one of the Herons procured by me [A. wardi, nobis]. They were feeding on a mud bar at low tide. I was once concealed in the low brush near a small pool watching three Louisiana Egrets chasing minnows, when two of them making for the same minnow squared off for a knock-down, while the third coolly appropriated the prize, leaving the combatants situated like complainant and defendant at the close of a law suit. In all my observations of the Herons I have seen nothing to lead to a conclusion that one of these birds held any particular antipathy against its own species while feeding. In the many squabbles between Herons on their feeding grounds the encounters occurred quite as often between different species as members of the same species. It may be that during the breeding season they are more friendly than at other times. In order that you may understand my opportunities for observing these birds, I enclose a rough map of Mound Key and surroundings, my camping place from January 20 till April 10. As you will see by the figures marked ... it was in the midst of their feeding grounds, these places being mud- and sand-bars, bare at low tide. Regarding the Reddish Egret, among many thousands of them I saw only one in the pure white plumage, and no white young; but one of my dark specimens has white feathers on the head and in the tail, while one of the secondary quills has the outer web chiefly white. My companion of last winter’s Florida trip reports that he saw no Reddish Egrets with white except on the secondaries.
“Regarding the large Herons [i.e., A. wardi], I am much inclined to think them a geographical variety ... the specimens being very uniform in color.... I examined some thirty nests at least, fifteen of which contained young, all being dark colored, with one exception. These birds are common in Southwestern Florida, and their nests are frequently found along the coast. From all the information at my command, connected with my own observations, I am almost convinced that the bird in question is separate and distinct from A. occidentalis and A. würdemanni, and the fact that Audubon found the former in immense numbers among the mangrove islands of Eastern Florida is strong evidence that he happened in the vicinity of one of their rookeries. As you will observe by examining the diagram of my camping place and noting the rookeries of large Herons ... these birds were quite common in that vicinity, while I saw only a few specimens of A. occidentalis. The white bird found in the nest with the blue might have come there from an adjoining empty nest, some 30 or 40 feet distant, as it could easily have done, being nearly full-grown. This surmise is strengthened by the circumstance that I saw a large white Heron on the island marked ‘*,’ and my companion killed a similar, if not the same, specimen on the large island marked ‘2,’ which he threw away, supposing it to be a common White Egret [Herodias egretta]. These I now believe to have been A. occidentalis; the other [H. egretta] was then laying its eggs, while the description of A. occidentalis corresponds to my recollection of the bird he killed. At the time, I was not familiar with the description of A. occidentalis.
“In the Little Blue Heron [Florida cærulea] and Reddish Egret (Dichromanassa rufa), where dichromatism appears to be an established fact, each species presents different phases and mixtures of both colors, especially the Little Blue, which shows almost every variety of curious markings of blue and white; while in the Reddish Egret, one specimen shows white on the head, tail, and wings, and others reported by Mr. Adams show white on the wings.
“As before said, I believe the bird to be a geographical variation of A. herodias, residing permanently and breeding in South Florida. I think that further search and observation will develop more evidence concerning A. occidentalis and A. würdemanni, which may result in confirming your theory of their being one and the same species. You will pardon my opposing your opinion, but my convictions are so strong that only the finding of white birds with blue young and more cases of blue parents with white young, or adults showing mixtures of both phases, would overcome them.”
Assuming that the large white birds observed by Mr. Ward were really a white phase of the dark-colored birds obtained by him, and which were so numerous in the locality, it certainly appears strange that so few of the former were seen. The case of the Reddish Egret, which he cites, affords, however, an exact parallel, and it is now considered established beyond question that “Peale’s Egret” (Ardea pealei Bonap.—a pure white bird) is merely a white phase of this species. As to the comparative rarity of these large white birds, in the locality where observed by Mr. Ward, militating against any theory of their specific identity with the dark-colored birds, it should be remembered that in the case of nearly every dichromatic species of bird this condition is more or less variable with locality. A pertinent example may be cited in the case of Demiegretta sacra, a Heron of wide distribution in the Far East. This species inhabits a considerable number of islands in the Polynesian group, and it has been noticed and recorded by naturalists who have visited that region, that on some islands all or nearly all the birds of this species are dark colored, on others all or nearly all are white, while on others still there may be a more equal proportion of the two phases. It may be remarked that the two phases in this species are even more distinct in coloration than in the case of Dichromanassa rufa, the colored phase being darker than in the latter species. Upon the whole, even admitting the possibility of the white young bird seen by Mr. Ward having of its own volition taken up its abode in a nest containing dark-colored young, I am strongly inclined to believe that it belonged to the same species with the latter, the question of its parentage (i.e., whether its parents were white or dark-colored birds) being a comparatively unimportant consideration, as affecting the main question. But in adopting the view of their specific identity a problem arises which in the light of our present knowledge appears unsolvable, and which may be briefly stated thus:—
The large “blue” Herons obtained by Mr. Ward are, in every respect as regards size and proportions, identical with Ardea occidentalis Aud. and A. würdemanni Baird; in coloration they agree exactly with the latter, except only in the pattern of the head and tint of the neck, which are precisely as in A. herodias. The bird in question is apparently “dichromatic,” having a white phase; hence, assuming that A. occidentalis and A. würdemanni are dichromatic phases of one species, it necessarily follows that white individuals of the bird in question would be absolutely indistinguishable from white examples of A. occidentalis! Still, in view of the fact that the colored phase differs from A. würdemanni in its most essential feature of coloration, i.e., the pattern of the head markings, it seems impossible to unite them, unless it can be shown that the type of A. würdemanni does not represent the perfect colored phase of that species.[[2]] There are hence several hypotheses which might be plausibly argued upon theoretical grounds, and which may be stated as follows: (1) That A. occidentalis, A. würdemanni, A. wardi, and A. herodias all belong to a single species, which reaches its extremes of variation in the first- and last-named; (2) That these names include three distinct races or species: A. herodias, which is never white; A. occidentalis, which is dichromatic (having separate white and colored phases), and A. wardi, also dichromatic, its white phase indistinguishable from that of A. occidentalis, and its colored phase distinguishable from that of the same species (A. würdemanni) by the different pattern and color of the head and neck alone; and (3) that there are two species, A. occidentalis and A. herodias, which in Florida hybridize on an extensive scale, producing the intermediate specimens which have been distinguished as A. würdemanni and A. wardi.
Of these hypotheses I have, after careful consideration of them all, concluded to adopt the second as being most consistent with known facts, and accordingly propose for the bird in question the name
486* Ardea wardi Ridgw.
Ward’s Heron.
With the following characters:—
Ch.—Colored phase exactly like A. würdemanni (= dark phase of A. occidentalis?), but with the head colored as in A. herodias. Differing from herodias in much larger size (culmen 6.50–7.00 inches, tarsus, 8.50–9.00 inches), lighter general coloration, and (in dried skin) light brown instead of black legs. Dichromatic; the white phase being indistinguishable from that of A. occidentalis (?).