Beetles are the most numerous and varied order of insects. Some are good for your garden but some are less popular!
What do beetles do in my garden?
Ladybirds in particular love to gobble up little garden pests such as aphids while violet beetles are nocturnal predators who spend the night hours hunting snails, slugs and other creatures which would eat our plants. Other beetles help to break down animal and plant debris but the more unfortunate ones become food for mammals and birds looking for a crunchy meal. If you have a healthy garden, you’ll lose count of the number of different beetles creeping around in the undergrowth.
How do beetles defend themselves?
Beetles are like miniature tanks with their very own armour plating covering their backs. Their exoskeleton is made of a tough, leathery substance called chitin. In adult beetles the chitin is modified and becomes very hard providing a good general protection. Unfortunately, this isn’t good enough against many predators so they’ve developed an array of different methods to cope with the hardships of garden life. Some use the art of camouflage and use their environment to protect them. Others are impressionists and mimic other more dangerous insects, such as wasps, to avoid predation, while some beetles produce foul tasting or poisonous secretions so that nothing wants to eat them. Larger beetles tend to do away with all these sophisticated methods and rely on good old brute force. Predators know that if they want to eat a beetle with large spiky mandibles, they’re going to be in for a fight!
What do beetles eat?
Beetles have adapted very well to almost all environments on the planet. Some are vegetarians and just eat plants, while others are carnivorous and will feed on other insects. Some species are very picky and will only feed on one type of plant or animal. Decaying matter is also a popular choice of food with some species feeding on dung and dead bodies. These beetles are like the hoovers of the natural world; it’s like having your own private cleaner in your back garden!
How do beetles reproduce?
In many beetle species, males are territorial and will fight off any other male contenders who come within their range. Pheromones play a big part in attracting females but competition for mates may be fierce. Some beetles duel to the death so that the strongest end up reproducing. Approaches to parenting vary between species with some mothers being very attentive and others simply laying the eggs and leaving them to fend for themselves.
- Beetles can be distinguished by their hard exoskeleton made up of several plates called sclerites. Their forewings have also developed into hard armour plates called elytra which, in flying species, serve to protect the delicate wings underneath
- Beetles make up about 40% of all insects with about 450,000 species worldwide
- The study of beetles is called coleopterology
- The shiny wing cases of some beetles have led to them being used as adornments by certain tribes and the ancient Egyptians considered some species of dung beetle as sacred
- Many beetles are considered to be pests for the damage they do to crops around the world. The boll weevil has cost the United States cotton industry about 13 billion dollars since it arrived from Mexico in the late 19th century!