Sample Page

The palmchat (Dulus dominicus) is a medium passerine bird endemic to the Caribbean island of Hispaniola (split between the Dominican Republic and Haiti). It is the only species in the genus Dulus and the family Dulidae, and is related to the waxwing family Bombycillidae and the silky-flycatchers in Ptiliogonatidae. Its name reflects its strong association with palms for feeding, roosting, and nesting.

In 1760 the French zoologist Mathurin Jacques Brisson included a description of the palmchat in his Ornithologie based on a specimen collected from the French colony of Saint-Domingue, modern Haiti. He used the French name Le tangara de S. Dominigue and the Latin Tangara Dominicensis.^[2] Although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature.^[3] When the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition in 1766, he added 240 species that had been previously described by Brisson,^[3] with one of them being the palmchat. Linnaeus included a brief description, coined the binomial name Tanagra dominica and cited Brisson’s work.^[4]

While Linnaeus placed the palmchat with the euphonias in the tanagers, it was realised in the 19th century that it’s closest relatives were the waxwings and silky-flycatchers.^[5] P.L. Sclater moved the palmchat to the subfamily Dulinae in his 1862 Catalogue of a collection of American birds, and the species was elevated to a full family by Robert Ridgway in 1904.^[6] During the twentieth and twenty-first centuries opinion has been divided on whether the three groups were three families or a single family.^[5]

The palmchat is the only species placed in the genus Dulus that was introduced by the French ornithologist Louis Pierre Vieillot in 1816.^[7][8] A second species, Dulus nuchalis, was described by William Swainson in 1838, who attributed it to Brazil. The species was referred to as the white-naped palm chat by Ridgway, who did not know where it was from but assumed it must be from Hispaniola.^[6]

The species is monotypic, meaning it has no subspecies.^[8] Birds from the Gonâve Islands were described as a subspecies, D. d. ovideo, by Alexander Wetmore in 1929, on the basis of plumage differences and a slightly larger size,^[9] but this subspecies has not been accepted by other scientists.^[5] Wetmore named his subspecies after Gonzalo Fernández de Oviedo y Valdés, an early Spanish colonist to the Caribbean whose chronicles included accounts of the species.^[9]

Palmchats are medium-sized passerines, about 18–20 cm (7–8 in) in length and weighing 41–52 g (1.4–1.8 oz). Their appearance has been described as “moderately odd” by the Handbook of the Birds of the World, having relatively small heads, short yet deeply-curved yellow-horn bills and long necks. The wings are long and rounded, and the feet are large and strongly-clawed. The plumage is olive-brown above, and heavily streaked with brown below. Their rumps, as well as the uppertail-coverts, are dark greenish-olive, and the tail is brown. The primary feathers are yellow-green. They lack the soft silky plumage of the waxwings or silky-flycatchers. Adults show no sexual dimorphism in plumage, but the males have slightly larger wings. Immature birds resemble the adults but have darker throats and forenecks and buff-coloured rumps.^[5]

The species is endemic to the island of Hispaniola (in both Haiti and the Dominican Republic), and the adjacent Saona and Gonâve Islands, where it is common and widespread. It inhabits areas from sea level to 1,800 m (5,900 ft). The species occupies a wide range of habitats, most commonly open savanna where royal palms are most common, but also other open, semi-open or even broadleaf and pine forest. They are only absent from the highest mountains and dense closed forest. Where its food trees are present, it has adapted well to human-modified habitat such as farmland city parks and gardens.^[5]

The species is not thought to be migratory. Some have suggested that it may undertake localised movements after the breeding season, but the only evidence is a slight reduction in observed birds duirng this period in some areas. The species is a poor disperser and is not found on islands close to Hispaniola, although there is one uncorroborated report of a palmchat from Jamaica.^[5]

Palmchats are very sociable birds, often seen in small flocks containing several pairs, which will roost closely together with their bodies in contact.

The breeding season is mainly from March to June. The birds build large, messy, communal nests of twigs in the crowns of palms, preferring Puerto Rico royal palms, (Roystonea borinquena) and Hispaniolan silver thatch palms (Coccothrinax argentea). They will also less frequently nest in cana (Sabal domingensis) and coconut palms (Cocos nucifera),^[10] or other trees and even telephone poles may be used.^[5] There has even been one unusual report of a palmchat nest on a rock off the coast.^[11] The whole nesting structure may be up to 2 m across, containing up to 30 adjoining nests with their own separate chambers and entrances. The females lay clutches of 2-7 (mean 4) eggs The eggs of the palmchat are quite variable. They can range in colour from pale green to beige, off-white and cream and can be marked with brown, purple–grey or grey scrawls, speckles or blotches.^[5] Other bird species will occasionally nest alongside palmchats in their communal nests, including Ridgway’s Hawk, White-necked Crow, and Ashy-faced Owl.^[12]

Palmchats feed on predominately on fruits and berries, but will also feed on leaves, flowers and some insects. One study found that 57 out of 58 samples of stomachs examined contained only plant matter. Royal palms form an important part of the diet, but they will also take the fruits of other palms and of the gumbo-limbo tree. Insects, when taken, are gleaned from trees or taken on the wing. Food is almost always obtained from trees, more rarely bushes, and never from the ground.^[5]

They are voluble and noisy birds, with a large repertoire of gurgling and cheeping sounds constantly used in their social behaviour.^{[citation needed]} With their loud whistles, they are able to imitate the calls of hawks and kestrels which may be a surprise coming from their tiny bodies. They are typically classified as songbirds, but hardly ever make a coherent song.^[13]

The palmchat appears to have benefited from human activities in Hispaniola, having adapted well to human-created habitats, and the species is one of if not the most common birds on the island. While some declines have been recorded,^[5] it is not approaching the thresholds for the population decline criterion of the IUCN Red List (i.e., declining more than 30% in ten years or three generations), it has been evaluated as being of Least Concern.^[1]

The palmchat is the national bird of the Dominican Republic.^[14]

• Don Roberson’s Bird Families of the World Archived 2008-11-04 at the Wayback Machine
• The Endemic Birds of Hispaniola