K migrácii a zimným nocoviskám piniek severských (Fringilla montifringilla) na Slovensku On migration and winter roosting sites of bramblings (Fringilla montifringilla) in Slovakia

Abstract

Here we describe our knowledge on invasive occurrence and behaviour of ramblings on several roosting sites in Slovakia. Altogether we recorded three invasive occurrences of bramblings from 2004 to 2017. In 2004 we recorded invasive behaviour during the spring migration in Hrhov, SE Slovakia. Sex-ratio of 739 mist-netted individuals was biased to females (1:1.9). In winter periods 2008/2009 and 2016/2017, after beech mast, we observed wintering with massive roosting on two sites in E (Gelnica) and C Slovakia (Klenovec) with ca. 3.5 and 0.5 millions of individuals, respectively. Sex-ratio was strongly biased to males (>2.8:1) in both localities.

Keywords

• brambling
• irruption
• winter roosting