Friends of the Fowey Estuary

First Session 11.05.19

Bird of the Week - Blackcaps

Blackcaps are increasingly familiar visitors to Cornish gardens during winter but are less conspicuous in summer despite being one of our commonest warblers. The easiest way to find them now is through their beautiful song. The first birds are usually heard in the second half of March but numbers  have grown significantly in the last few days. On a survey yesterday we heard at least four males singing in some woods near Golant. (The reason why blackcaps only start singing in late March is that our winter birds leave to breed in Central Europe whilst our own breeders have wintered further south.)

The males sing frequently and can be heard during the heat of the day when many other species are silent. They also sometimes sing at night which has led, together with the musical quality, to the epithet of 'Northern Nightingale'.  I have attached a link to an example of their song. As with many species there is significant individual variation and it is the structure of the song which is often the give away rather than any individual notes. It is easy to confuse blackcaps with their close relative, the garden warbler - not found in the sort of gardens most of us have. Garden warblers, however, are much less common.

Blackcaps  are associated with shrubs so can be heard in large gardens as well as in scrub and woods. The male often sings from deep cover but some show themselves and demonstrate their distinctive black top of the head, which could just be confused with marsh or willow tits, both of which occur in the Fowey Valley although in very much smaller numbers. Females and juveniles have brown caps.



The least often identified of our common birds?

Is probably the whitethroat. This was apparently not always true: it appears as one of the four birds that Robert Browning evokes in ‘Home Thoughts from Abroad’, which implies his readers would know this homely name. Why might things have changed?  Although their numbers crashed in 1968/9, because of drought on the migration route through the Sahel, whitethroats still breed widely in Britain. The RSPB estimates 1.1 million pairs, only slightly fewer than the 1.2 million for blackcaps and goldfinches. (These figures are educated guesses and need to be treated with caution but give some idea of relative abundance.)

The apparent loss of familiarity may partly stem from urbanisation. Whitethroats do not much patronise gardens, they are birds of scrub and woodland edge, and it is on and around garden feeders rather than in the country that many species have become familiar. In addition, whitethroats are generally quite shy. And, unlike blackcaps, they are only here for a few spring and summer months.

The most common way of detecting them is through the male’s song. (A link to a recording is attached.) The song could just be confused with that of the whitethroat’s close relatives, the blackcap and garden warbler. However, the most common whitethroat song is shorter and tends to sound rushed and jerky. It also is a bit scratchy and generally lacks the rich notes of blackcap and garden warbler.

Although song is often delivered from cover the best chance of seeing the bird is when the male performs a song flight, this song is generally longer and richer, or obligingly sings from the top of a hedgerow tree.  The male’s plumage is elegant. It really does have a prominent white throat, which is set against a grey head rusty brown wings and a buffish chest.  A behavioural feature is a frequent flicking of the longish white edged tail. The female is drabber with a brown head and a duller throat. In size the whitethroat comes between goldfinch and chaffinch.

Amongst the places that you can find whitethroats locally  are coastal scrub, on the Downs at Golant, around woodland edges and in farmland with thick hedges. The end of May is a good time to listen for them as our resident and early migratory species are singing far less or even falling silent.