Black redstart (Phoenicurus ochruros)

CC-BY Kostis Tzortzakakis

Looks like
The black redstart is - as the name says - a bird with a very dark head and body which contrast with its red tail. The females and juveniles have a lighter, more brown-grey colour. It is a small bird (ca. 14 cm) with a thin beak which it uses to pick up small invertebrates, such as insects, spiders and snails, but also nuts.
Where and when to spot it
The black redstart is easily recognized by its behaviour: it often sits on exposed spots and wags its tail. It can be seen during winter on rooftops, in archaeological sites, on fields, sitting on poles, in harbours, and many other places.
Interesting facts
City buildings often resemble the mountainous rock faces in which it builds its nests.