Ecological segregation of woodcreepers (Dendrocolaptidae) in the state of Rio de Janeiro, Brasil

The 48 Neotropical woodcreepers feed in a variety of ways, such as among Mauritia palm fronds (e.g., Cinnamon-throated Woodcreeper Dendrexetastes rufigula ), as obligate ant followers (e.g., White-chinned Woodcreeper Dendrocincla merula ) or by probing the ground (e.g., Scimitar-billed Woodcreeper Drymornis bridgesii). However the typical foraging method of a member of this group, which lacks obvious ecological counterparts in the rainforests of South-East Asia and Africa (Pearson 1977, G. H. Orians, pers. comm.), is to glean bark-living arthropods while ascending a tree trunk, rather in the manner of a Certhia treecreeper. The bird then crosses, often by a descending glide, to begin the ascent of another trunk. Determinants of a species' preferred feeding station are thus likely to include height Above ground and trunk diameter, both of which are readily measured, and bark characteristics. The woodcreepers are therefore potentially admirable (and hitherto unused) subjects for quantitative studies of niche overlap. I report here on the overlap of the woodcreepers of the rainforests of South-East Brasil.