Reproductive biology

The reproductive season depends mostly on the local rainfall regimes. Some species tend to nest during the dry season and others during the rainy season. All broadbills make pendant nests. Common nest materials include fibers, strips of leaves from monocotyledonous plants, such as grasses, bamboo, and palms, and other leaves. Smithornis also interweave black fungal strands. Spider webs and co-

The colorful bill of a black-and-red broadbill (Cymbirhynchus macrorhyn-chos). (Photo by Doug Wechsler/VIREO. Reproduced by permission.)

coons, moss, and other materials camouflage the nests. Except in Smithornis and Calyptomena, nests are suspended from the tips of branches, and are hard for predators to reach. Locating the nests above water further deters predators. Cymbirhynchus suspends its nests 5-26 ft (1.5-8 m) above rivers or other water bodies. While protected from predators, nests in the lower range are often destroyed by rising water levels.

Two to six eggs are laid. With the possible exception of Calyptomena, both sexes build the nest. Male parental care appears to be common in most species. The dusky and long-tailed broadbills may even be cooperative breeders as more than two individuals of the species have been observed around nests. As an interesting side note, female green broadbills' heads protrude from the nest entrance. Why? Nobody knows. Much needs to be learned about broadbill reproductive behavior.

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