Fraction of bird species for which the model included vegetation variables as the first (V1), second (V2) or third (V3) most important variables.

Species are grouped by their degree of habitat specialization based on the number of habitat types they use for breeding and feeding. High specialization means the species use one habitat type (N = 90), mid specialization means the species use two habitat types (N = 51) and low specialization means the species use three habitat types (N = 9).本数据集依据物种繁殖与觅食所利用的栖息地类型数量，按照栖息地特化程度对其进行分组：高度特化指物种仅使用1种栖息地类型（N=90），中度特化指物种使用2种栖息地类型（N=51），低度特化指物种使用3种栖息地类型（N=9）。