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Breeding bird response to juniper woodland expansion

Steven S. Rosenstock·Charles van Riper
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Abstract

In recent times, pinyon ( Pinus spp. )-juniper ( Juniperus spp. ) woodlands have expanded into large portions of the Southwest historically occupied by grassland vegetation. From 1997-1998, we studied responses of breeding birds to one-seed juniper ( J. monosperma ) woodland expansion at 2 grassland study areas in northern Arizona. We sampled breeding birds in 3 successional stages along a grassland-woodland gradient: un-invaded grassland, grassland undergoing early stages of juniper establishment, and developing woodland. Species composition varied greatly among successional stages and was most different between endpoints of the gradient. Ground-nesting grassland species predominated in uninvaded grassland but declined dramatically as tree density increased. Tree- and cavity-nesting species increased with tree density and were most abundant in developing woodland. Restoration of juniper-invaded grasslands will benefit grassland-obligate birds and other wildlife.

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Steven S. Rosenstock, Charles van Riper. 2001. Breeding bird response to juniper woodland expansion. https://doi.org/10.2307/4003238

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