A female Blackcap appeared on fat balls in our Fairlight garden on Christmas Eve, and was joined by a male on Boxing Day. We recorded wintering Blackcaps for the first time last year, when one arrived on the similar date of Dec 20.
These wintering Blackcaps are a relatively recent phenomenon, which was first noted in the 1960s, and are mostly recorded in gardens. They come from Central Europe-not UK birds staying here-and are able to survive due to warmer winters [!] and garden feeding. It is believed that because they have less distance to travel to their breeding grounds than those wintering further south, they arrive earlier, secure better territories and mate with each other, increasing the population with this habit.