04-May Nightjars & Heathland Harmonies

Summary

As dusk falls on London’s forgotten heaths, an eerie churring rises—like a phantom motorbike echoing across the bracken. This is the nightjar’s spellbinding song, weaving mystery into May’s twilight. But can you spot the stonechat’s pebble-click warning? Or distinguish the grasshopper warbler’s reeling whisper from a true insect’s buzz? Return on 04 May to uncover the secrets of the capital’s rarest birdsong—where meadow pipits mimic squeaky bikes, and whinchats sing sweet, stolen melodies in the wild edges of the Thames.

Article

Heath Birdsong

Compared with woodland, areas of grass and heathland are relatively silent places, although stonechats and meadow pipits can generally be relied upon to break the silence. The stonechat used to be commonly heard on London’s gorse-covered commons but now seems to prefer the wilder edges of the lower Thames. It has a brief, poorly projected warble not unlike a hedge sparrow. It is its alarm or anxiety note that you normally hear first. Like so many other birds, this sounds like two pebbles knocked together loudly. Once this is heard in an open area, the male can usually be located on the top of a nearby bush. He may well be trying to distract your attention and lure you away from a nearby nest. In contrast, the meadow pipit produces an accelerating series of sip sip sip notes as well as sounds not unlike a squeaky bike.

04-May Nightjars & Heathland Harmonies Section Image

04-May Nightjars & Heathland Harmonies Section Image

In the same habitat it is worth listening out for the whinchat, identified visually by its distinct eye-stripe. It has a very short undistinguished warble which is slightly richer and sweeter than that of the stonechat. A more common sound is the highly strung scratchy warble of the whitethroat with its abrupt ending. He is prone to singing slowly, occasionally and churring loudly if you get too near. He also has a memorable private song which you almost have to put your ear beside the bush to hear.

04-May Nightjars & Heathland Harmonies Section Image

04-May Nightjars & Heathland Harmonies Section Image

The tree pipit is a much rarer bird of heaths, but has one of the most unforgettable songs in this often bleak habitat. It is in two parts; the first is canary-like and then there is a series of attractive ‘pwee-pwee-pwee’ notes rising in pitch. It is all the more special as there is considerable variation between birds and is usually delivered from either the top of a tree or during a circular display flight.

On more lonely heaths covered in bracken, one of the most unusual of all wildlife sounds in London can be heard. This is the famous churring of nightjars, which starts just as the sun goes down. Unromantically, it has been described as being like a lawn mower, spinning wheel or distant motorbike travelling at high speed. Other more romantic adjectives used are weird, unforgettable, evocative, even hypnotic.

04-May Nightjars & Heathland Harmonies Section Image

04-May Nightjars & Heathland Harmonies Section Image

There are rhythmic waves of sound which seem to come from one direction and then another. The song, if you can call it that, consists of a record-breaking nineteen hundred notes a minute. It is best heard on warm, windless nights when it can carry for over half a mile. There has always been an air of mystery associated with this sound, especially as the bird is not seen during the day. Nightjars were associated with that other miscreant of the night, Puck, and were even called puck birds in Sussex. A similar sounding bird, but usually heard in marshy areas, is the grasshopper warbler. W. H. Hudson, the naturalist, thought there was no difficulty in separating the two birds, saying the song of the grasshopper warbler was ‘a mere whisper by comparison’.

04-May Nightjars & Heathland Harmonies Section Image

04-May Nightjars & Heathland Harmonies Section Image

The song of the grasshopper warbler is more like a fishing line, rapidly unravelling, hence its alternative name of ‘reeler’. It is sometimes less helpfully compared to a grasshopper or mole cricket. It also seems to change volume, possibly due to the bird turning its head, and tends to be less loud at the beginning and end of its warbling. It can go on for five minutes without a pause and is sometimes heard at night.

All these birds are not easy to find but Rainham and Dartford Marshes are good places to listen out for stonechats, whinchats and even perhaps grasshopper warblers. Set-aside farmland along the river Thames can also be productive as is Walthamstow marshes for both tree and meadow pipits. Nightjars do occur on some nearby Surrey commons such as Chobham common but are easier to find on more southerly ones such as Thursley Common.

04-May Nightjars & Heathland Harmonies Section Image

04-May Nightjars & Heathland Harmonies Section Image