Sexual habitat segregation in Black-throated Blue Warblers wintering in Puerto Rico.

Abstract

Sexual habitat segregation by Black-throated Blue Warblers (Dendroica caerulescens) wintering In Puerto Rico appears to be related to the canopy height and successional stage of montane forests. A stepwise discriminant function analysis was based upon altitude and 13 vegetation variables measured at warbler capture sites in three study areas. Female capture sites differed from those of males by having smaller trees, more foliage at 0-2 m and 4-6 m above the ground, and less foliage at 12-15 m above the ground. Using a classificatory discriminant function analysis with four vegetation variables it was possible to classify correctly 60 of 64 warbler capture sites in three study areas. Thus female Black-throated Blue Warblers were most common in the younger, shrubby-sapling stages at higher elevation and males were more common in the older, taller forests of lower altitude. Forests of intermediate canopy height and age had an equal mix of males and females. The possibility that the observed habitat segregation is maintained by behavioral dominance and/or intrinsic "preferences" is discussed.

Citation

Wunderle, Jr, Joseph. (. 1992. . Sexual habitat segregation in Black-throated Blue Warblers wintering in Puerto Rico.