千葉県清澄山系におけるサンコウチョウの営巣環境

抄録

The breeding habitat of the Black Paradise Flycatcher Terpsiphone atrocaudata was studied in the Kiyosumi mountains, Chiba Prefecture. Five nests were found in the study area in 2004. The song areas in the three sites that were intensively monitored were similar in size (approximately 1.9 ha). All song areas comprised forestry plantations with low tree density, which appeared suitable for the aerial feeding habits of this species. All nest sites were near forest borders and the tree densities beneath and around them were low. The nests were built on vines or dead branches with canopy cover, but branches and leaves below them were scarce. These features of the nest sites probably provide access to the nests for parents and defense against nest predators. Although the Black Paradise Flycatcher is said to inhabit dark forests, my results suggest that it may prefer (at least partially) forests with low tree density as breeding habitats.