© Copyright: Images: Jari Peltomäki, M. & W. von Wright: Svenska fåglar (Kansalliskirjasto, The National Library of Finland). Recording: Jan-Erik Bruun. All rights reserved.
- Family: Warblers – Sylviidae
- Appearance: A fairly large and attractive warbler. Male greenish grey with a distinctive black cap. Female brownish grey with a reddish brown cap.
- Size: Length 13.5–15 cm, weight 15–24 g.
- Nest: In a small shrub or herbaceous plant at a height of 0.1–1.75 m. More solidly built than nest of Garden Warbler. Made of dry plant stalks, lined with hair, roots and fine grass, bound with spider’s web strands.
- Breeding: 3–6 eggs laid in May, incubated by both parents for 10–11 days. Fledglings remain in nest for 9–11 days.
- Distribution: Breeds in herb-rich deciduous and mixed forests in Southern and Central Finland, only sparsely further north where range extends as far north as Kainuu. Finnish breeding population estimated at 30,000–50,000 pairs.
- Migration: Nocturnal. “Leaves Finland August–October, returning May–June. Winters in East Africa and around the Mediterranean. Some birds occasionally overwinter in Finland. * Diet: Invertebrates, berries.
- Calls: A harsh “chek”. Melodious song similar to song of Garden Warbler, but more flute-like, especially in later stages.
Male Blackcaps are mainly greyish in colouring with distinctive black caps. Females are more brownish grey with a reddish brown cap. Juveniles resemble females, though juvenile males begin to grow black feathers on their black caps in early autumn during a partial moult. Blackcaps have dark bluish grey legs, black or dark brown beaks, and brown irises.