Thursday, Jan. 27, 2005
* Japanese name:
* Scientific name: Lanius bucephalus
* Description: At first glance, bull-headed shrikes look like large (20-cm-long) house sparrows, albeit they have thick, hooked, black bills and are more strongly colored, with black and white feathers in their wings, rust flanks, gray-brown backs and brown caps with a distinctive, horizontal black stripe running across the eye. Bull-headed shrikes are songbirds, though their song consists of a scratchy warble and a rather harsh "chack" call. Both the male and female put on weight when they are in the breeding phase. The female lays 3-7 eggs.
* Where to find them: Bull-headed shrikes can often be seen perching in a high position, on bushes or trees or telephone cables. Stone lanterns are also favored sites in gardens and temples, as are bamboo groves. They can be seen all over Japan from Hokkaido to Kyushu, in gardens, river areas and farmland. In Hokkaido, they are migratory, moving to Honshu in the winter. They can be seen yearlong, and live for up to 7 years.
* Food: The Latin name of this genus means "butcher," and that gives a clue to its diet, as does the specialized, very sharp bill. Bull-headed shrikes are sit-and-wait predators, preying on insects and small birds and mammals. In effect they are miniature birds of prey. When food is caught (despite the shrike's gentle appearance, prey such as sparrows are speared with the bill) it is often kept in a "larder" -- impaled on a thorn or wedged between twigs on a branch.
* Special features: Perhaps because they feed on a range of other animals, shrikes are a good indicator species. This means that they are useful to ecologists monitoring environmental change, especially that due to climate change. Until quite recently, they were rather common, but populations (especially, for example, in Osaka) have fallen dramatically. Shrikes are sensitive to environmental conditions, and the size of their eggs changes according to food availability; the earlier eggs are laid, the greater the chance that the nestling will survive. Because of this, females will even reduce the size of their eggs in order to lay them quicker.
* Special features:Bull-headed shrikes are also sometimes tricked by cuckoos, which lay their eggs in the shrike's nest and leave them to be raised.