Blackcaps are a common typical warbler (Sylvia) on the rise in the UK, having experience an uncommon shift in migratory behaviour over the past 25 years. They are a lively species, with an air of elegance, expressing a plumage of simple muted colour. Observe a Blackcap in your garden, and note its chunky appearance. It is about the same size as a Chaffinch. Furthermore, it has been noticed that Blackcaps are lovers of towns and cities, very bossy and can be quite aggressive with other birds when feeding in the garden.
Both sexes are predominantly grey in colour, yet can be distinguished by the colour of their caps: males are easily identified by their striking black caps, while females are differentiated by their somewhat more muted chestnut brown caps. According BTO research, more males than females migrate to the UK over winter in a bid to establish their breeding grounds prior to spring the following year. However, asked whether or not there was a bias towards male Blackcaps, most respondents mentioned they saw no more than a single Blackcap in their gardens, so no statistically significant evidence was provided for any gender bias.
In the UK, Blackcaps are common birds, classified as Green Status by the RSPB. There are approximately 1,200,000 breeding pairs in the UK.