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What The Fact?? LADY BEETLES

Lady Beetles, Lady Birds, Lady Bugs, what do you call them?

They are adored by kids because they are so sweet and cute, but these Little Beetles are really very, unladylike eating machines and play the role of teeny tiny superheroes in your garden. 

Lady Beetles eat aphids, scale, mites, caterpillars, thrips, moth and beetle larvae, fungi (including powdery mildew), pollen, nectar, honeydew, and each other. They can eat 5000 aphids their lifetime, and if their preferred food runs out, they will eat whatever is available until it comes back. If there is no food available, they will just fly away and find some more.

Given their prodigious appetite, it comes as no surprise that lady beetles are commonly used for biological control, but did you know that Australian Lady Beetles were the world’s first successful biological control? 

Saviours of Citrus

In 1888 the Californian citrus industry was on its knees due to Cottony Cushion Scale, so Albert Koebele came to Australia where citrus trees were healthy despite the presence of the scale (which is native to this region). He took 514 Vedalia beetles back to California where they multiplied so quickly, and ate so many scale insects, that they literally saved the Californian citrus industry within a year! More recently, Vedalia beetles were introduced to the Galapagos Islands because the same scale insect was attacking threatened plant communities, and once again they saved the day. Insect Superheroes!

So the problem wasn’t the scale insect, it was that it had travelled to where it was out of its ecological context. Without predators, the scale population boomed. Introduce its predator, the scale is brought under control. Simple! It is the same in your garden, people don’t really have pest insects, they just don’t have functioning ecosystems!

Defense

Lady beetles tend to be brightly coloured, so how do they not get eaten by birds? 

When they feel threatened, foul tasting ooze comes from their leg joints, and birds learn to associate the taste with the colouring and avoid eating them again. 

Indentify

Taking a close look at your Lady Beetle’s colour and pattern will tell you a lot about them. No, the number of spots doesn’t tell you its age, but it might tell you what species it is. If you count 28 spots, then you have the imaginatively named 28 spotted lady beetle, which is the black sheep of the family because they eat plants. They especially like beans, cabbages, potatoes, tomato, eggplant, and blackberry (pulling out this weed can help to control their numbers).

If your Lady Beetles are black with yellow spots, they are fungus eaters which can be relocated onto pumpkins with powdery mildew. If they are red / orange and black, then they are one of the many insect predator species and can be welcomed anywhere in your garden.

Random fact: The collective noun for a group of Lady Beetles is a loveliness.

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