Plants invasions may have important impacts on populations of the native species including birds. We can expect that these impacts will vary in respect to the ecological context where the species live. Consequences of such a variation are, however, still poorly understood. For this purpose, we studied the responses of bird communities to the invasion of Sosnowsky’s hogweed (Heracleum sosnowskyi) along a gradient from open to forest habitats in relation to the ecological traits of bird species. The research was conducted in southern Poland in spring 2019. Birds were counted twice on 52 site pairs (control and Heracleum). As expected, the invader had generally negative impact on the total number of birds, their species richness and abundance of all bird guilds except the birds living in the ecotone zone. However, the magnitude of these impacts significantly differed along the habitat gradient: the response of ground dwellers and farmland birds to the invasion was more negative towards open habitats, while the opposite pattern, i.e. a more negative response towards forest habitats, was observed in birds associated with bushes. Individual bird species, however, sometimes differed in the direction and severity of the response to the invasion from the guild to which they belonged. Taken together, our results indicate that the impact of Sosnowsky’s hogweed depended on habitats preferred by individual species and whether this alien changed their habitat. This finding should be taken into account when designing management plans for the affected species.

植物的入侵可能会对包括鸟类在内的本地物种的种群产生重要影响。我们可以预期，这些影响会因物种所居住的生态环境而异。然而，这种变化的后果仍知之甚少。为此，我们研究了鸟类群落对Sosnowsky的猪草（Heracleum sosnowskyi）入侵的响应，该梯度是从开放到森林的栖息地与鸟类的生态特征相关的。该研究于2019年春季在波兰南部进行。在52个站点对（对照和Heracleum）上对鸟类进行了两次计数）。正如预期的那样，除了生活在过渡带地区的鸟类以外，入侵者通常对鸟类总数，物种丰富度和所有鸟类协会的种群数量产生负面影响。但是，这些影响的幅度沿栖息地梯度存在显着差异：地面居民和农田鸟类对入侵的反应对开放栖息地的负面影响更大，而在鸟类中观察到相反的模式，即对森林栖息地的负面反应与灌木丛相关。但是，个别鸟类有时在其所属公会对入侵的反应方向和严重程度方面有所不同。综上所述，我们的结果表明，Sosnowsky的猪草的影响取决于单个物种偏爱的栖息地以及该外星人是否改变了其栖息地。