Grasshoppers and Bush-crickets

Grasshoppers and bush-crickets are two families of insects in the order Orthoptera. They are creatures of warmth and sunlight and have a beautiful angularity. For centuries the grasshopper has been a symbol of joy associated with high summer and country pleasures: dancing, singing and music making.

 Grasshoppers make their songs by rubbing their wing cases against little nodules on their legs, crickets by rubbing their wings together – this process is known as stridulation. Sound is the way they communicate through the tangle of grasses, rushes, brambles and tree boughs where they live. Each species has a unique call. In the UK there are 11 kinds of grasshopper and 23 types of bush-cricket.  The most familiar song is probably the Field Grasshopper’s brisk chirp, repeated at short intervals. However these insects are wary and usually stop singing when you get too close. In both crickets and grasshoppers the males have a calling song to attract females to them. They also have a courtship song to woo the female, often a low, soft scraping. The third lyric is one of warning or rivalry to deter other crickets from stealing their mate: a loud trilling noise.

Grasshoppers are mostly vegetarians, come out in the daytime and have short, stubby antennae while crickets are omnivorous and have long antennae.  Grasshoppers leap, using their big upper hind-leg muscles, as these muscles contract the slender tibia are forcefully straightened, catapulting the grasshopper into the air. Some species can leap up to 80 centimetres, which is as if a human could jump the length of a football pitch in one go.

The Meadow grasshopper, like the rest of its species, hatches from an egg into a nymph, usually moulting five times before reaching its adult form. It lives in damp unimproved pastures and meadows without herbicide. This habitat is becoming alarmingly scarce. Similarly, as bogs and fens are drained or overgrazed, the Large Marsh Grasshopper is increasingly rare.Chris Haes, an authority on the creatures, refers to their beauty, “… the prominent veining of the wings; the herring bone muscles on the hind legs and the sharply chiselled faces…”  The insects are many shades of green; some are dark, rich browns and the Large Winged Coneheads, discovered recently on a Norwich allotment, are deep lime green with a black stripe running the length of their back. The adults die before winter, having already laid their eggs in soil, tree bark or plant stems in the warmth of summer.

On a warm summer evening last July a Common Oak Bush cricket came leaping through my bedroom window, landing on my shoulder. It is attracted by light and I was reading under a lamp. It jumped onto my hand and I studied its long antennae, handsome compound eyes and the yellowish streak running down its light green back. It is found in a variety of trees, including oak, and uniquely it drums with its feet on the leaves to give a very quiet sawing buzz that other bush crickets can hear clearly. Its abdomen tapered to a long ovipositor, an egg laying tube, so it was female and would lay its eggs individually in tree bark, moss or lichens. Its predators are amphibians, like frogs, birds and reptiles. I set it on the windowsill and away it leapt into the sheltering dark. It is one of the crickets that feed on small invertebrates.

The Field Grasshopper is about 20mm long, brown with tinges of green. It gives short brisk chirps, repeated after a gap and sounding as if a pen is being rubbed down a plastic comb.

Although some species are struggling to survive in Britain, Roesel’s Bush-cricket has expanded its range in the last decade. The hotter, drier summers have encouraged them northwards and they are often heard in Norfolk on unsprayed verges and field edges.

Gardens are now very important for the survival of these lovely insects.  Grasshoppers and Bush Crickets support the ecosystem; birds, bats amphibians, reptiles, fish and small mammals all benefit from eating them. They are part of the great food chain that sustains life.

To help protect these amazing insects:

• Leave lawns, hedgerows and verges a bit wilder.
• Don’t use pesticides or chemicals and look after local trees.

Let’s try and keep the riff of the dark Bush Cricket with the pulsing rhythm of its wings. Let’s keep the trills and songs of all these splendid creatures.

 

References:

Bugs Britannica, Peter Marren (author), Richard Mabey (editor). 2010. Chatto and Windus

Countryfile

 August 2024