Systematics

First described under name Ardea rufa Boddaert 1783, based on “Aigrette rousse” of Buffon (1783) and plate of “L’Aigrette rousse, de la Louisiane” by D’Aubenton (1780). Because name preoccupied by Ardea rufa Scopoli 1769 (associated with another species), binomial Ardea rufescens Gmelin 1789 has priority for this species. White-morph Reddish Egret was known, initially, as Peale’s Egret, Ardea pealii, Bonaparte 1826, and was regarded as an immature plumage by Audubon (1843). It was not until 1870s that observations of mixed pairs and mixed broods of both “Peale’s” and “Reddish” herons finally demonstrated existence of 2 color morphs in this species (Ridgway 1878).

Formerly placed in monotypic genus Dichromanassa; transfer to Hydranassa with Louisiana (Tricolored) Heron also previously suggested. Now usually classified in genus Egretta since revision of Ardeidae by Payne and Risley (1976).

Minor differences reported in size and plumage of dark-morph adult (heavier pigmentation of body-feathering and color of ornamental plumes), but these poorly characterized and based on small sample sizes. No differences in immature plumages described.

Two weakly differentiated subspecies recognized by Payne (1979), although species formerly divided into 3 races (e.g., Palmer 1962, Blake 1977). Variation poorly understood, and validity of named forms not firmly established.

Egretta rufescens rufescens (Gmelin, 1789). Found along Gulf Coast of U.S. and e. Mexico, including Yucatán Peninsula and adjacent coasts; also Bahamas, Greater Antilles, Caribbean coasts of Central America and n. South America. Includes “ E. r. colorata (Griscom, 1926)”, type locality Quintana Roo, Mexico; said to have ornamental plumes strongly tinged vinaceous instead of being uniform slate, wing-coverts edged basally with brown, head and neck of adult slightly paler, and possibly larger average size than Gulf Coast state’s birds (Blake 1977 and references therein). Map of subspecies in Palmer (1962) suggests that “ colorata ” also occurred on west coast of Mexico south of Sinaloa; earlier authorities restricted “ colorata ” to the Yucatán, whereas Blake (1977) expanded it to include Bahamas and Greater Antilles. Differences more likely represent seasonal stage of appearance, with fresh plumage, rather than geographic variation (Paul 1991).

E. r. dickeyi (van Rossem 1926). Type locality San Luis I., Gulf of California, Mexico. Although published analysis of specimens beyond type locality apparently lacking, breeding range of E. r. dickeyi said to include populations on remainder of Baja Peninsula coasts, as well as coasts of Sonora and Sinaloa (birds south of there—e.g., Oaxaca—of undetermined race). Also said to occur south to El Salvador (Payne 1979). Vagrants to California assumed to involve this race, although no analysis of specimens exists. Plumage said to be darker than E. r. rufescens, with head and neck Cameo Brown to Chocolate of Ridgway’s color standards and body more plumbeous (darker plumage compared with Gulf of Mexico birds reiterated in Payne 1979); 4 adult males from Cameron Co., TX, averaged slightly shorter in wing and tail length versus 5 adult males from type locality (van Rossem 1926).

Phylogenetic analysis of osteological characters suggests Reddish Egret not closely related to other Egretta herons (Payne and Risley 1976, McCracken and Sheldon 1998). Similarities in nuptial plumes and courtship behaviors noted, with Snowy Egret and Tricolored Heron, among North American herons, and ecological similarities with Little Egret (E. garzetta) and Eastern Reef Heron (E. sacra) noted by Payne and Risley (1976). Also see Sheldon and Slikas 1997 .