White helmetshrike

Prionops plumatus

SUBFAMILY

Prionopinae

TAXONOMY

Prionopsplumata Shaw, 1809, Senegal. Up to nine races described. Variation affects size, amount of white in wings, and characteristics of frontal feathers and crest.

OTHER COMMON NAMES

English: White-crested helmet-shrike, curly-crested helmet-shrike; French: Bagadais casqué German: Brillenwürger; Spanish: Alcaudón de Copete Yelcobé.

PHYSICAL CHARACTERISTICS

7.4-9.8 in (19-25 cm); 0.88-1.3 oz (25-37 g). A relatively large species; sexes similar. Mainly black on upperparts, but with white wing-stripe; wholly white on underparts; head whitish with stiff frontal feathers and long, straight crest; eyes yellow surrounded by yellow wattle. In flight, obvious white patch in wings and white outer feathers in tail. Juveniles are similar, but duller, with no crest and no wattle. Race cristatus (Ethiopia) has no white in the wings and its long crest curls forward. Race ta-lacoma (parts of eastern and southern Africa) shows a grayish head and has no long crest.

DISTRIBUTION

Most common and widespread helmet-shrike, exclusively in sub-Saharan Africa. Absent from some parts of south, central-western and eastern Africa.

HABITAT

Woodlands and wooded savannas, sometimes in suburban gardens outside breeding season. Occurs up to 5,900 ft (1,800 m) in Kenya.

BEHAVIOR

Highly gregarious in all seasons. A given group generally numbers up to seven birds, but up to 22 have been recorded together outside the breeding season. The group defends a home range covering about 50 acres (20 ha) (10-75 acres [5-30 ha]). When searching food, birds fly from tree to tree and may be seen anywhere between ground and canopy. Local movements are known, but not yet fully understood; they appear to be favored by drought years.

FEEDING ECOLOGY AND DIET

All kinds of arthropods, mainly insects and particularly butterflies and moths, as well as their caterpillars. Small reptiles are sometimes taken.

REPRODUCTIVE BIOLOGY

Monogamous cooperative breeder. Only one dominant pair breeds and is assisted by what are thought to be closely related birds. Over the vast breeding area, egg-laying may occur almost in any month. Lays two to five eggs, most often four, in a cup-shaped nest made of bark that is cemented and decorated with spider web. It is placed a few yards (meters) above the ground in a tree. Incubation done by all the birds, but probably mostly by the dominant pair, for about 18 days. Young stay in the nest about 20 days; they are still fed by the group when about two months old.

CONSERVATION STATUS

Not threatened.

SIGNIFICANCE TO HUMANS None known. ♦

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