Christmas beetles emerge each summer around Christmastime after waiting underground all year. They are easy to spot; their shimmering metallic bodies set them apart from a lot of the insect world.
If you leave a light on during hot summer nights—especially in the east of Australia – you may find these nocturnal flying Christmas decorations in a bit of a frenzy in its glow.
Christmas beetle babies are c-shaped grubs that spend a whole year growing up in small chambers just underneath the surface of the soil. They eat plant roots and decaying organic matter, so keep your grass well nourished and mulch your garden regularly to provide plenty of baby Christmas beetle food.
Adult Christmas beetles love to eat the leaves right at the top of Eucalyptus trees. Preserving your local native eucalypts and planting a few in your garden provides a smorgasbord for the annual Christmas beetle gathering.
Enjoy their beautiful colours, but if they overstay their welcome, just turn off your outside lights or pull down the blinds and they’ll know it’s time to head home. Christmas beetles can take a hint.
Be a Backyard Buddy
The appearance of Christmas beetles is a reminder that the end of the year festive season is coming; they’re also really beautiful and fascinating to watch.
A lot of Christmas beetles come in golden brown or green colours, but the further north you travel in Australia, the more amazing their colours can be. In northern Queensland, you can even find Christmas beetles that are violet or have colourings a bit like an opal.
Christmas beetles like:
- Moist, but not too wet, environments.
- Grassy woodlands.
- Mature eucalypt leaves.
But they don’t like:
- Being stepped on. Heavy spring rains and thunderstorms provide the perfect conditions for Christmas beetles to hatch out of the soil. Especially if it rains in the later afternoon, be sure to watch where you step on the lawn. You might walk right into the middle of a huge bunch of brand new Christmas beetles.
- Losing all of their food sources. Reduction of our native woodlands, especially near cities and towns, has meant that beetles don’t have as many places to feed.
- Long droughts and very dry conditions that make it harder for their babies to hatch.
Be a Buddy to Christmas beetles
- Keep your garden in balance with native eucalypts. Too few trees in your area will mean that the Christmas beetles will all collect on the one tree. Your tree will most likely grow back, but the hungry beetles will certainly strip a lot of the trees leaves while they feast.
- Keep your lawn healthy and use native grasses. Christmas beetle larvae will eat the roots of your grass, but keeping it well nourished and watered will help the grass stay healthy and feed the baby beetles too.
- Helping to protect local woodlands so that Christmas beetles will have a variety of food sources and places to lay their eggs, not just in your garden.
- Spraying pesticides on the beetles. It won’t solve the problem because more beetles will keep on coming. Pesticides will also hurt a lot of the other important native insects and animals that help to keep a balance in your garden.
- Worrying too much about your trees. Big groups of Christmas beetles can eat quite a lot of leaves from one tree if there is no other food source. Their feasting frenzy might look like it is doing a lot of damage, but Christmas feasts are always short and they prefer the mature leaves to the fresh new shoots. If you are worried about having too many beetles, encouraging magpies, currawongs and possums into your garden will help to keep your numbers of beetle guests down.
- Giving your garden too much water over winter. Christmas beetle larvae like to hatch after heavy rains in spring, but soil that is waterlogged for a long time isn’t good for the larvae as they grow.
Don’t be surprised if Christmas beetles:
- Start crashing into things or land on you. Christmas beetles are not the most coordinated critters in your backyard. After a big night of flying around bright streetlights they can get a little woozy, but Christmas beetles are very gentle buddies to have. If they land on you it’s a great opportunity to say hello and take a closer look at their beautiful colourings.
- Suddenly disappear after a few weeks. There are two things on the mind of a Christmas beetle once they hatch: eating and mating. Once that’s done, it’s mission accomplished.
A few more Christmas beetle facts
- A Christmas beetle’s colouring comes from special layers of reflectors built into their hard shells.
- Christmas beetles have clubbed antennae and spiky legs that help them grip on to leaves as they eat, but if you disturb an adult Christmas beetle in a tree it will just fall to the ground.
- The Christmas beetle is a type of scarab beetle and is related to the rhinoceros beetle and dung beetle.
- There are around 35 different types of Christmas beetle found in Australia: most grow to about 3 centimetres in length.