Condor’s Top Cited, #4: Assessing Tree Avoidance by Prairie Birds

FIGURE 2. Plots comparing the effect of increasing grass variables versus increasing woody vegetation variables on four grassland bird species.

We’re in the home stretch – after this week, only three more papers to highlight from each journal! The Condor‘s third-most cited paper from 2014 and 2015 was A multiscale assessment of tree avoidance by prairie birds by S.J. Thompson, T.W. Arnold, and C.L. Amundson, which appeared in the August 2014 issue.

Thompson, Arnold, and Amundson conducted point counts on 35 patches of fragmented grassland habitat in Minnesota and modeled how the density of various bird species was related to habitat characteristics at multiple scales. Of the four species they focused on – the Savannah Sparrow, Clay-colored Sparrow, Sedge Wren, and Bobolink – the densities of three, the Savannah Sparrow, Sedge Wren, and Bobolink, were negatively associated with woody vegetation and were predicted to increase two- to fourfold with tree removal.

The authors recommend focusing tree removal in grassland habitat on features that have the most effect relative to their area, such as lines of trees along fences and isolated woodland patches in otherwise open habitat. All bird species in the study were affected to some extent by the broader-scale landscape, suggesting that the surrounding habitat will impact the efficacy of local patch management.

Read the full paper at