Removal of cattle grazing correlates with increases in vegetation productivity and in abundance of imperiled breeding birds

Biological Conservation
By: , and 

Links

Abstract

Livestock grazing is the most prevalent land use practice in the western United States and a widespread cause of degradation of riparian vegetation. Riparian areas provide high-quality habitat for many species of declining migratory breeding birds. We analyzed changes in vegetation and bird abundance at a wildlife refuge in southeastern Oregon over 24 years, following cessation of 120 years of livestock grazing. We quantified long-term changes in overall avian abundance and species richness and, specifically, in the abundances of 20 focal species. We then compared the local responses of the focal species to population-scale trends of the same species at three different large spatial scales. Overall avian abundance increased 23% during the 12 years after removal and remained consistent from then through year 24. Three times as many species colonized the survey sites as dropped out. Of the focal species, most riparian woodland-tree or shrub dependent, sagebrush obligate, and grassland or meadow taxa increased in abundance or remained stable locally. As these species were generally of conservation concern, the population increases contradicted regionally declining or stable trends. In contrast, most riparian woodland-cavity nester species decreased in abundance locally, reflecting disruption of aspen stand dynamics by decades of grazing. Avian nest parasites and competitors of native species declined in abundance locally, matching regional trends. Restoring riparian ecosystems by removing livestock appeared to be beneficial to the conservation of many of these declining populations of migratory birds.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Removal of cattle grazing correlates with increases in vegetation productivity and in abundance of imperiled breeding birds
Series title Biological Conservation
DOI 10.1016/j.biocon.2019.108378
Volume 214
Year Published 2019
Language English
Publisher Elsevier
Contributing office(s) Forest and Rangeland Ecosystem Science Center
Description 108378
Country United States
State Oregon
Google Analytic Metrics Metrics page