ABSTRACT Capsule: There was significant variation on the incidence of road traffic mortality across bird species, due to seasonal and weather effects but also due to differences between years. Aims: To assess patterns of mortality due to traffic collision for six common bird species over a period of nine years in relation to seasonality and weather. Methods: Road mortality surveys were performed on four road sections from 2005 to 2013 in southern Portugal. The analysis controlled for survey frequency, and carcass persistence and detectability. Results: Overall, bird mortality decreased over time and was generally higher during spring and summer months. The lack of strong relationships between the weather variables and the observed mortality patterns suggests the existence of additional factors important in explaining the observed trends. Conclusions: Our study provides evidence that bird mortality due to collision with vehicles may change between years and was highest during the breeding season. This could have population consequences, and highlights the need to further address large temporal scales in roadkill research.

中文翻译：

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地中海地区道路交通碰撞导致鸟类死亡的时间模式

摘要：由于季节和天气影响以及年份之间的差异，不同鸟类的道路交通死亡率发生率存在显着差异。目的：评估六种常见鸟类在 9 年内与季节性和天气相关的交通碰撞死亡率模式。方法：2005 年至 2013 年在葡萄牙南部的四个路段进行了道路死亡率调查。分析控制了调查频率、胴体持久性和可检测性。结果：总体而言，鸟类死亡率随着时间的推移而下降，并且在春季和夏季月份普遍较高。天气变量与观察到的死亡率模式之间缺乏密切的关系表明存在对解释观察到的趋势很重要的其他因素。结论：我们的研究提供的证据表明，由于与车辆碰撞造成的鸟类死亡率可能会随年份而变化，并且在繁殖季节最高。这可能会对人口产生影响，并强调需要在道路杀伤研究中进一步解决大的时间尺度问题。