We're Losing Bees And Butterflies But Gaining Cockroaches And Flies

Nearly half of the world's insect species are at risk of extinction, threatening the collapse of nature.

It's been dubbed 'the largest extinction event on Earth'.

Bees, ants and beetles are disappearing eight times faster than mammals birds and reptiles with the total mass of insects plummeting by 2.5 percent each year, according to a new study published in the journal Biological Conservation.

It's a big deal.

There are an estimated 10 quintillion insects on earth -- 10,000,000,000,000,000,000 -- outweighing humanity by 17 times.

More of these, please. IMAGE: Getty

They have ruled the world for millions of years and are essential for the function of the earth's ecosystems.

They do everything from providing food for small animals, pollinating 75 percent of the world's crops and replenishing soil, to limiting pest numbers.

The paper reviewed 73 existing studies published around the world in the past 13 years and concluded that one-third of insect species are 'endangered', while 40 percent could be extinct within decades.

Crop sprayer IMAGE: The Creative Drone via Getty

Intensive agriculture is being blamed for the plummeting numbers, particularly the heavy use of pesticides.

While researches have also noted Urbanisation and climate change are significant factors.

“That means the elimination of all trees and shrubs that normally surround the fields, so there are plain, bare fields that are treated with synthetic fertilisers and pesticides," University of Sydney's Francisco Sánchez-Bayo told The Guardian. 

“If insect species losses cannot be halted, this will have catastrophic consequences for both the planet’s ecosystems and for the survival of mankind,” he said. 

A bee-eater catching a bee in Italy IMAGE: Angelo Butera via Getty

If insects go, birds, reptiles and amphibians and fish could follow suit.

“If this food source is taken away, all these animals starve to death,”  Sanchez-Bayo said.

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But here's the catch, not all species are on the way out, in fact, resilient pests like cockroaches and household flies, which have evolved a resistance to pesticides, could actually increase in number.

The number of cockroaches could soon rise. IMAGE: Getty

"It's quite plausible that we might end up with plagues of small numbers of pest insects, but we will lose all the wonderful ones that we want, like bees and hoverflies and butterflies and dung beetles that do a great job of disposing of animal waste," Prof Dave Goulson from the University of Sussex told the BBC

Researchers say the world must change the way it produces food, noting that organic crops had more insects, and refrain from overusing pesticides.