Here’s why you should keep spiders and insects onside

Pesticides kill unwanted bugs but often also harm the ones you want working with you.

Pesticides kill unwanted bugs but often also harm the ones you want working with you. Photo: University of Queensland

A house crawling with spiders and insects sounds like a bad nightmare, but a choice selection of bugs around the home can work to your benefit.

Sarah Bonney, a PhD candidate at Charles Darwin University and organiser of the Darwin Insect Festival, said most people gave insects and invertebrates a bad rap.

“Insects actually play a very big role in our world,” she said.

“Without them we wouldn’t have a lot of food, they keep our soil healthy, and they basically keep the world turning.”

But as well as doing their bit for the environment, beetles, bugs and other invertebrates can also work for us.

And according to Ms Bonney and Macquarie University researcher Dr Lizzy Lowe, the first step is to put down the pesticide and understand which bugs are best to have around.



Web-weaving spiders are great at catching flying insects in the garden and around the home. Photo: ABC

Because of the wide variety of species that can live both inside and outside your home, spiders can be a very effective means of controlling insect populations.

And if you are able to live with the knowledge that you are sharing space with spiders, they can make excellent housemates.

Dr Lowe specialises in the study of spiders and their role in urban environments.

“There’s basically only two spiders [in Australia] that you don’t want around — the redbacks and the funnel webs,” she said.

“They are probably best to be controlled, but every other spider will have a benefit in your house.

“They eat pests, they actually control the numbers of other spiders, and the more different types of spiders you have around the more balanced your back garden or your house’s ecosystem will be.

“You’ll have less cockroaches, you’ll have less mites and other small critters crawling around and it will benefit the whole household.”

Carnivorous insects

praying mantis

Praying mantis are among the most efficient of all predatory or carnivorous insects. Photo: ABC

Insects that eat other insects can be among the most advantageous creatures to have around the family home.

And encouraging them to stick around can be as simple as letting nature take its course.

“Try not to use too many pesticides to kill unwanted insects,” Ms Bonney said.

“The problem with them is that they affect the good bugs just as badly, if not worse, than the bad ones.”

In the garden, carnivorous or predatory insects are adept at controlling pest species that you may not want chewing on your plants.

“Praying mantis are absolutely fascinating insects, they’re really honed predators that are fantastic at catching things like bugs, flies, beetles and all sort of things that are eating your plants,” Dr Lowe said.

She said lady beetles, often revered for their prettiness, were also great predators.

“We call them biocontrols because they’re a way of controlling pests in your garden without using pesticides, by using other insects.”



Flies may be annoying when they get in the house but they are a vital part of the ecosystem. Photo: Flickr: Vinoth Chandar

Having swarms of flies buzzing about inside the home is far from healthy, but in the garden and around your home they have an important role to play.

“Flies are known as the world’s pooper-scoopers,” Ms Bonney said.

“They actually break down a lot of the poo and detritus that gets left around in the ecosystem, and all those nutrients are released back into the environment.”

For Dr Lowe, flies serve a very different purpose around the home.

“To me, the most important role of flies is in the ecosystem, in the food web,” she said.

“They are a really important source of food for a lot of insects and spiders as well.

“If we got rid of them in our ecosystems we’d basically be in a lot of trouble because a lot of things would be going without food.”


Stay informed, daily
A FREE subscription to The New Daily arrives every morning and evening.
The New Daily is a trusted source of national news and information and is provided free for all Australians. Read our editorial charter.
Copyright © 2024 The New Daily.
All rights reserved.