Unusual blue tit influx puzzles european gardeners; citizen science needed

A blue wave: the phenomenon explained

Across gardens in Northwest Europe this autumn, a striking sight has captivated observers: a surge in the number of Blue Tits (Cyanistes caeruleus). This isn't just a slight increase; Natagora, a leading nature conservation organization, is sounding the alarm and calling on citizen scientists to participate in a large-scale bird census during the last weekend of January. This represents a rare opportunity to gauge whether this influx signifies a permanent shift in the behavior of these typically sedentary birds.

Why are these normally sedentary birds migrating?

The Blue Tit is generally considered a resident species, meaning it typically remains within a defined territory year-round. However, this autumn has witnessed remarkable waves of individuals crossing multiple countries—a phenomenon Natagora describes as an