Habitat Requirements of the Golden-Cheeked Warbler: Management Implications

Abstract

Characteristics of nesting and wintering habitats of goldencheeked warblers (Dendroica chrysoparia) were studied from 1973-1978. Golden-cheeks are obligatively dependent on Ashe juniper (Juniperus ashei) for nesting materials and singing perches, but are equally dependent on scrub-oak (Quercus durandii breviloba) for foraging substrates. Golden-cheeks preferred to forage (73.6% of total observations) in hardwood species. Stepwise discriminant analysis suggested that quality nesting habitat differs from poor nesting habitat by having older (?40 yrs.) Ashe juniper, lower juniper densities and higher densities of oak (juniper-oak ratio= 1.35 to 1). Structure of scrub-oak (mostly Q. oleoides) in the wintering habitat (La Esperanza, Intibuca Dept., Honduras) was structurally similar to that in the nesting Golden-cheeks were observed feeding in the shrubby understory. The golden-cheeked warbler (Dendroica chrysoparia) is a rare bird inhabiting the so-called in the Edwards Plateau region of west-central Texas. Golden-cheeks have been the center of controversy involving clearing of Ashe juniper (Juniperus ashei) for range improvement and commercial harvesting for fence posts and aromatic oils; yet, no study to date has dealt quantitatively with habitat requirements of these birds. Pulich (1976) conducted an in-depth study on the natural history of golden-cheeks. He noted that the warblers are obligatively dependent on Ashe juniper for nesting habitat, and that golden-cheeks require large blocks of mature (?50 years old) Ashe juniper. He further noted that: Only older cedar brakes with some variation in age provide the necessary requisites of warbler habitat. Previous studies by Johnston et al. (1952) and Huss (1954) characterized the vegetative composition of golden-cheek nesting habitat as juniper-oak; juniper composition ranged 14-50% (of stems per acre), while oaks made up 20-70%. My study was initiated to obtain quantitative data on nesting and wintering habitats of golden-cheeks, as well as, to develop a habitat management strategy for these rare birds.