Yesterday we had a visitor with the most fantastic legs! We have been listening to the Test match, now – quite literally – ‘cricket’ came alive in the kitchen…
As I went closer our unusual visitor leapt. At his best, Olympic gold medal winning long jumper Greg Rutherford jumped 8.51m. That is four and a half times his body length. To achieve this he needed a long run up and lots of clapping from the crowd. Our visiting cricket was 2cm long and was leaping 60cm from a standing start, a distance 30 times its body length. Phenomenal.
Do you know the difference between a grasshopper and a cricket? I was delighted to see this cricket as I had recently been told that the length of antennae distinguishes them – grasshoppers have short antennae, crickets long. However, what counts as ‘long’? Well, once I had seen this cricket, I realised ‘long’ is seriously long – its thin, intermittently waving and curling antennae were longer than its body. In comparison, grasshoppers antennae are short and stubby.
Another difference between the two is that crickets are usually nocturnal, while grasshoppers are about in the day. I was lucky to have such a good view of this cricket: usually you need to go out at night with a torch to see them. Crickets’ legs are covered with spines and spikes, used to strike and hold down smaller prey insects. Gardeners will be pleased to have them as they eat aphids! Grasshoppers on the other hand only eat vegetation. Both – unfortunately for them – are important sources of food for larger creatures, including birds.
The Orthoptera society produce a great guide to crickets and grasshoppers. My visitor turned out to be a Roesel’s bush-cricket, easily identified (once you know) by the creamy-yellow or green horseshoe shape mark on each shoulder. One of ten species of bush-cricket in the UK, Roesel’s bush crickets used to be confined to the south-east coast, but have spread across the south of England in the last few years. It likes damp meadows and rough grassland and may have used uncut road verges to spread further north.
Crickets’ and grasshoppers’ sing to attract and court mates. Roesel bush-crickets’ song is described as like the noise from overhead electric pylons. Not so attractive to our ears but obviously works for them! These insects’ song is caused by stridulation – the rubbing of body parts against each other to create sound. To ‘sing’ crickets rub grooves, or pegs on one wing vein against similar grooves on the veins of the other wing – something like having one’s own inbuilt violin. They amplify this scratchy sound by lifting their wings to form a loud hailer, and with a oval device a bit like a drum’s skin in their wing surface, called a mirror. To hear, they have ‘ears’ on their front pair of legs, just below their knees.
Grasshoppers have a set of pegs running down the inside thick part of their legs. They ‘chirp’ by rubbing these pegs against a vein on their forewing. In this recording of a field grasshopper you can almost hear how this sound is created. Instead of being on their front knees, grasshoppers’ ears are at the base and sides of their abdomen. The sound of leather on willow is one of the sounds of an English summer that we have just got back. The sound of these creatures in a grassy field – by day and night – is without doubt another.
When it is sunny, go to any area of longish grass and look out for grasshoppers – they will start leaping in all directions. Even the small patch of long grass by the pavement at the bottom of Newmarket Road is full of them. Spot their ‘ghosts’: in order to grow, crickets and grasshoppers have to shed their skins – or exoskeletons (external skeletons) – several times. To get the idea, think of a human bursting out of their trousers. Look across the tops of the grasses and you may well see a pale white skin that has been left behind. They look like ghosts, but are actually signs of new life and growth.
Tip: if you want to collect a skin, take a pot as they are very light and easily blown away with a breath of wind.
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Thanks, Jo .. this is fascinating! .. your knowledge is amazing!
Much love to you all,
Joan and Bill.