Shrikes: Laniidae - White Helmet-shrike (prionops Plumatus): Species Accounts
Animal Life ResourceBirdsShrikes: Laniidae - Physical Characteristics, Habitat, Diet, Behavior And Reproduction, Conservation Status, White Helmet-shrike (prionops Plumatus): Species Accounts - GEOGRAPHIC RANGE, SHRIKES AND PEOPLE
Physical characteristics: Also known as white-crested helmet-shrikes, white helmet-shrikes are distinguished by their helmet-like ruff of stiff white feathers around their bills and foreheads that blend into a long, erect crest. They range in size from 7.4 to 9.8 inches (19 to 25 centimeters) and typically weigh between 0.9 and 1.3 ounces (25 to 37 grams). Males and females look very similar, but the female is slightly larger. The birds' crown, sides of head, and cheeks are gray, with a dark bar on the sides of and around the neck. Otherwise, the upperparts are greenish black, with a narrow white stripe down the wing. Undersides are bright white, including the underside of the tail. The white-crested helmet has a greenish black bill, yellow eyes surrounded by a yellow wattle, and orange-yellow legs and feet. Young birds are similarly colored, but more subtly.
Geographic range: White helmet-shrikes are native and locally common in sub-Saharan Africa from the western side of the continent east to Eritrea and south along the eastern side of the continent to South Africa. They may also be found in southern Africa from northern Namibia east and south across northern Botswana and South Africa and south into Mozambique and Swaziland.
Habitat: The dominant breeding pairs live in deciduous broad-leaved woodlands, while subordinate, nonbreeding individuals often move farther out during the winter into savannah and cultivated gardens outside cities. This species will rarely breed in eucalyptus (yoo-kah-LIP-tus) plantations.
Diet: Like the majority of the Laniidae family, white helmet-shrikes forage, search for food, in the canopies of trees as well as on their branches and trunks, and on the ground. They also catch insects in the air on occasion. This species spends most of its foraging time in the winter on the ground, and stays in the trees during warmer seasons. White helmet-shrikes especially favor foraging in areas of recent fires. In general, they eat mainly caterpillars, moths, termites, and grasshoppers, but will also eat spiders and lizards.
Behavior and reproduction: White helmet-shrikes are often seen moving among trees in small flocks of three to twenty-four individuals. Their coloring and undulating, wave-like, flight pattern are unmistakable, as is its group chorus, which has been described as sounding like "krawow, krawow, kreee, kreee, kreepkrow, kreep-krow." They are extremely sociable birds, one calling bird will always cause the others in the group to respond. Growls, bill snaps, and squeaks are also used to alert others about prey, intruders, nesting needs, etc. Dominant and subordinate individuals have different calls. The birds are resident, but not sedentary, and leave their breeding territories to wander their local habitats after the young leave the nest.
White helmet-shrikes become sexually mature at two years of age, although the vast majority never get a chance to breed until they are five years old. This is due to the hierarchical (hi-uh-RAAR-kih-kul), rank, structure of their populations, in which there is only one mating pair allowed within a "family party." Other members of the family party are assistants to the dominant pair. The dominant pair chooses the nest site, but all members of the group help build the nest, incubate the clutch, and guard and feed the nestlings.
Dominance is asserted by nudging others away from food and getting prime spots at the roost, but obvious aggression is unusual. These shrikes are extremely social birds and tend to do everything together: preening, attacking intruders, and foraging. Their noisy communications echo through their forest homes as they coordinate activities among themselves. Groups of helmet-shrikes often join with other species of birds as they move around their territory. However, one group of white helmet-shrikes will firmly defend its territory against another group, with displays of bill snapping, calling, and stretching their heads upward. The face-off ends when members of one group fly at the other, hopefully causing the offending group to retreat.
White helmet-shrikes and people: Although many shrikes are still hunted by humans, white helmet-shrikes have no other special significance to people.
Conservation status: White helmet-shrikes are not threatened. ∎
- Shrikes: Laniidae - Loggerhead Shrike (lanius Ludovicianus): Species Accounts
- Shrikes: Laniidae - Conservation Status
- Other Free Encyclopedias