Impacts of invasive plants on songbirds: Using song structure as an indicator of habitat quality

Abstract

Invasive species can alter habitat quality over broad scales, so they pose a severe threat to songbird populations. Through our long-term research program supported by BEMRP, we have found that changes in habitat quality induced by exotic plants like spotted knapweed can lead to subtle yet profound changes in songbird populations. For example, in knapweed-invaded habitats compared to those dominated by native vegetation, we detected no change in abundance of adult chipping sparrows -- but we observed delays in breeding that led to reduced breeding productivity and increased turnover of adults between breeding seasons. Knapweed invasion caused declines in native plants that led to declines in insects serving as key food sources for songbirds and other vertebrates. This resulted in diminished habitat quality for songbirds.

Parent Publication

• ECO-Report - Scientific independence: A key to credibility

Citation

Ortega, Yvette. 2007. Impacts of invasive plants on songbirds: Using song structure as an indicator of habitat quality. In: EcoReport. Missoula, MT: Bitterroot Ecosystem Management Research Project: 6, 14.