Reddish Vale Country Park
Even if you hear grasshopper warblers they can be difficult to locate due to the ventriloquial effect of their singing.
The grasshopper warbler has declined in numbers in Britain, particularly from the 1960s to the 1980s, even though it appears to be increasing in continental Europe. The British decline may be linked to problems with breeding habitat, and winter survival may also vary, as favoured wintering areas may flourish one year and be dried out the next. It is now a Red List species following a population decline of more than 50 per cent over the last 25 years.
This species’ breeding distribution is patchy across Europe, and the European subspecies seems to spend the winter in the western half of West Africa. Other subspecies occur eastwards to Mongolia, wintering in India. The few British ringed birds that have been recaptured were found wintering in Senegal and The Gambia.
Observations in Senegal, where large numbers of wintering birds have been seen, indicate that most have left the country by early February. Information from bird observatories in Britain shows that the earliest arrivals are on the south coast in late March, but the main influx takes place later, during the second half of April and early May. The majority of birds turn up on the western side of Britain, with relatively few seen at east coast observatories.
Grasshopper Warblers migrate at night, and on occasion large numbers have been killed at lighthouses. On 29 August 1968, a total of 111 Grasshopper Warblers was found among almost 600 dead warblers on Bardsey Island, Gwynedd.
A Grasshopper Warbler sings with its bill wide open, turning its head from side to side. This gives a ventriloquial effect; it is almost impossible to place exactly where the song is coming from, and its intensity alters constantly. Singing birds are especially vocal around dusk and dawn.
This small passerine bird is a species found in short dense vegetation, often close to water. 4–7 eggs are laid in a nest on the ground or a tussock.
This is a medium-sized warbler, 12.5–13.5 cm long. The adult has a streaked brown back, whitish grey underparts, unstreaked except on the undertail. The sexes are identical, as with most warblers, but young birds are yellower below. Like most warblers, it is insectivorous.