The Chiffchaff is a tiny leaf warbler about the size of a Blue Tit. Chiffchaffs are summer visitors to Britain, and are among the first migrant songbirds to arrive in the spring. They winter in the Mediterranean and western Africa.
In spring and summer, they have brownish-green upper parts and buff underparts. There is a dark eye stripe through the eye, a pale eyebrow (supercilium) and a thin pale eye ring.
The Chiffchaff is practically indistinguishable from the Willow Warbler, though it is less yellow, has shorter eyebrows and often has darker legs; remember the phrase: "the riff-raff have dirty legs". They also tend to be found towards the tops of trees and bushes, in woodland areas, whereas Willow Warblers are more often lower down (and in more open, scrub areas), and seem more nervous - constantly flicking their tail downwards.
|10-11 cm (4")
|15-21 cm (6-8")
|6-10 g (¼-½ oz)
The best way of distinguishing the Chiffchaff from the Willow Warbler is by their song. The Chiffchaff's song sounds like its name "chiff chaff" or "zilp zalp", while the Willow Warbler's song is a melodic rippling phrase that rises quickly before slowly dying away.
The Chiffchaff's and Willow Warbler's calls are almost identical, "hweet" or "hooeet".
In the autumn, both species rarely sing so the call is often the easiest way of finding the warbler.
Chiffchaffs feed on insects, such as midges and other flies, and caterpillars and moths, which they find by foraging in tree canopies and among bushes. Indeed, Phylloscopus means leaf explorer and Chiffchaffs search the undersides of leaves where aphids congregate and feed on the tree's sugary sap.
The female Chiffchaff does the nest building. The domed nest is built on or very close to the ground in tall grass, bushes, or wall creeping plants. Dead vegetation (stems and leaves) are used for the construction, and a thick feather lining.
The duties of incubating the eggs are performed by the female. The eggs are about 15 mm by 12 mm, smooth and glossy, white with purplish or black markings. The young birds are fed by the female only.
Most British breeding Chiffchaffs migrate to the Mediterranean and West Africa for the winter, though there are an increasing number over-wintering in Britain. The majority of these winter Chiffchaffs are birds from Scandinavia and mainland Europe, though some are "resident" British birds.
The population of Chiffchaffs fell in the 1960s and 1970s owing to harsh conditions in and around the Sahara, Africa. Since then their numbers have recovered and are now stable or even slightly increasing, possibly because of milder winters.