Guadeloupe Woodpecker

Identification

The Guadeloupe woodpecker is a medium-sized, robust woodpecker species measuring 26–28 cm (10–11 in) in length, and with a mass of 86–97 g (3.0–3.4 oz) in males and 69–78 g (2.4–2.8 oz) in females. It is distinct in its appearance within its genus, and unlike other species of Melanerpes, males and females do not present a marked sexual dimorphism in their plumage; they are entirely black with gradual reflections ranging from dark red to burgundy on the ventral plumage, dark blue on the back, and metallic blue on the wing tips. Males have a wingspan of 42.5 cm (16.7 in) compared with 40.5 cm (15.9 in) in females). The black coloration of the Guadeloupe woodpecker may be an advantage in drying feathers by exposure to the sun and fighting against humidity, and the black feathers may be resistant to abrasion, but no definitive explanation has been advanced by the scientific community. This woodpecker is solitary animal, a social behavioral trait that is often associated with plumage monomorphism.<p>The legs, which terminate in four toes in a zygodactyl arrangement, are gray-green to gray-blue and powerful, with highly developed talons. The talons are curved for gripping bark with the tip of the claw; this represents an adaptation to living on trunks and branches of trees. The eyes are 6 mm (0.24 in) in diameter (pupil 2 mm (0.079 in)) with dark brown irises. The beak is entirely black and is between 15 and 20 percent longer and more robust in males; this is the main criterion for recognizing the sex of individuals. The size of the female's beak is equal to that of her head while that of the male is distinctly longer.<p>As with all woodpeckers that are adapted to piercing wood, the nostrils on the culmen have small feathers to protect respiration and mucus glands to trap dust. The pterygoid protractor muscle, which is highly developed in woodpeckers, is important for adapting to shock absorption by uncoupling the beak, which can move laterally, from the skull to minimize the transmission of kinetic energy to the brain and eyes. There is also a specific pterygoid bone in Picidae compared to other birds. They have a specific cancellous tissue between the skull and the beak, with a displacement of the attachment of the greater horn of the hyoid bone to the quadrate bone, as well as a reinforced sternum and keel. These elements maximize energy dissipation and shock absorption for the bird during impact. The specific, long tongue of the Picidae is cylindrical and is about twice the size of its bill. The tongue is the result of an evolution of the hyoid apparatus with two parts; one bony at the end is equipped with small hooks, the other cartilaginous lengthens under the action of a branchiomandibular muscle that attaches to the branch of the mandible, split, anchoring on the anterior part at the base of the culmen, surrounding the skull from behind with its two branches, descending on either side of the spine, esophagus and larynx, which pushes the hyoid horns and tongue out of the beak.<p>Juvenile birds are similar to adults but have duller, dark brown plumage. The life expectancy of individuals is greater than five years and estimated to be between eight and ten years.

Taxonomy

Described in 1830 by René Primevère Lesson in the genus Picus, the Guadeloupe woodpecker was given its binomial name, Melanerpes herminieri, after the naturalist Félix Louis L'Herminier, who studied in Guadeloupe and wrote numerous works on birds. The name of the genus Melanerpes comes from the Greek melas meaning "black" and herpēs meaning "climber". In the local Guadeloupe Creole, it is called Tapeur or Tapé ("one who knocks"). It is also called Toto bwa or Toc-toc for its tapping noise.<p>The Guadeloupe woodpecker had been considered for some time to be in the monotypic genus Linneopicus before being classified in the genus Melanerpes. It may have evolved during the Pleistocene from the Puerto Rican woodpecker (M. portoricensis), which itself is derived phylogenetically from the red-headed woodpecker (M. erythrocephalus). The phylogenetic position diagram of the genus Melanerpes is the least-known among the family Picidae, whose divergence into the subfamilies Jynginae, Picumninae, and Picinae—to which Melanerpes belongs—dates from 30 to 20 million years ago in the Oligocene or lower Miocene.

Scientific name

Melanerpes herminieri

Authority

(Lesson, RP, 1830)

Order

Piciformes

Family

Picidae

Genus

Melanerpes

Range and habitat

Since the extinction of the Guadeloupe parakeet (Psittacara labati) and the Guadeloupe amazon (Amazona violacea) in the 18th century (if they existed), the Guadeloupe woodpecker is the only bird species that is endemic to Guadeloupe, and is the only woodpecker species found in the Lesser Antilles. It, along with two species of forest bats and two species of frogs, is one of the archipelago's five endemic animal species.<p>The Guadeloupe woodpecker is present on the main island from sea level to the upper tree line, at around 1,000 m (39,000 in) altitude, but is historically more common on island of Basse-Terre, where it has a preference for the island's east coast, than on Grande-Terre. It is absent from the dependencies of Guadeloupe (Îles des Saintes, Marie-Galante, and La Désirade).<p>The Guadeloupe woodpecker, an exclusively stationary species,, is found in a wide variety of forest types across the islands: it is most common in the tropical rainforest areas of Basse-Terre; in 1998, these rainforests had more than 70 percent of the population of the species in Guadeloupe, 5 percent were in deciduous areas, while the deciduous forests of Grande-Terre hosted about 20 percent, and the mangrove and swamp in the center of the archipelago held the remaining 5 percent.<p>In 2008, a study of Guadeloupean avifauna showed the presence of the Guadeloupe woodpecker in all zones of Guadeloupe National Park, where it prefers Côte-au-vent, the ombrophile massif on the eastern coast of the island, as well as the northwestern zone towards Deshaies north of the Côte-sous-le-vent. The species also seems to have colonized the Caribbean Mountains at the southern tip of Basse-Terre between 1998 and 2007. In 2008, Basse-Terre hosted three-quarters of the population of woodpeckers in the archipelago and Grande-Terre the other quarter. <p>The Guadeloupe woodpecker is a territorial bird but not particularly aggressive towards other birds, with which it seldom interacts. The species needs a territory of between two and five hectares (4.9 and 12.4 acres) per pair to live, and even ten hectares (25 acres) at the southern tip of the more-arid Grande-Terre.

Migration

Resident species

Behavior

Migration pattern: Resident species.

Conservation

Population trend: rising.

Population trend

rising