摘要 : Context Anthropogenic noise is relatively new to natural soundscapes and may have adverse effects on acoustically active species. In birds, adverse effects include changes in vocalization patterns. Helicopters and songbirds are ub... 展开 Context Anthropogenic noise is relatively new to natural soundscapes and may have adverse effects on acoustically active species. In birds, adverse effects include changes in vocalization patterns. Helicopters and songbirds are ubiquitous in protected natural areas but the effect of helicopter noise on songbirds has never been assessed. 收起