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jpak

(41,741 posts)
Mon Feb 11, 2019, 09:25 AM Feb 2019

Massive insect decline could have 'catastrophic' environmental impact, study says

Source: CNN

(CNN)Insect populations are declining precipitously worldwide due to pesticide use and other factors, with a potentially "catastrophic" effect on the planet, a study has warned.

More than 40% of insect species could become extinct in the next few decades, according to the "Worldwide decline of the entomofauna: A review of its drivers" report, published in the journal Biological Conservation.

Insect biomass is declining by a staggering 2.5% a year, a rate that indicates widespread extinctions within a century, the report found.
In addition to the 40% at risk of dying out, a third of species are endangered -- numbers that could cause the collapse of the planet's ecosystems with a devastating impact on life on Earth.

The report, co-authored by scientists from the universities of Sydney and Queensland and the China Academy of Agricultural Sciences, looked at dozens of existing reports on insect decline published over the past three decades, and examined the reasons behind the falling numbers to produce the alarming global picture.

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Read more: https://www.cnn.com/2019/02/11/health/insect-decline-study-intl/index.html

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progree

(10,864 posts)
2. So the insect mass has a half-life of about 27 years if it declines at a rate of 2.5%/year
Mon Feb 11, 2019, 09:28 AM
Feb 2019

Last edited Mon Feb 11, 2019, 10:24 AM - Edit history (1)

Assuming exponential decay, where each year it declines by 2.5% of whatever is left. Actually 27.3778 years.
(1-0.025)^27.3778 = (0.975)^27.3778 = 0.5000006 . "^" is the exponent symbol, e.g. 2^3 = 8.

With linear decay, they will be half gone in 20 years (2.5% * 20 = 50%).

Insect biomass is declining by a staggering 2.5% a year


They will be 92% gone in a century assuming exponential decay ( 0.975^100 = 7.95%, 100% - 7.95% = 92.05% )

At a linear rate, they will be all gone in 40 years.

TexasBushwhacker

(20,043 posts)
10. And the insectivores will die
Mon Feb 11, 2019, 12:52 PM
Feb 2019

Plenty of birds, small mammals, amphibians and reptiles eat insects. They will start to die off and the animals that eat them will die as well.

bronxiteforever

(9,287 posts)
4. Kick and recommend for visibility and humanity's sake
Mon Feb 11, 2019, 10:33 AM
Feb 2019

At what point do we, as a species, care?
“The collapse of civilisation and the natural world is on the horizon.” Sir David Attenborough

yaesu

(8,020 posts)
6. I blame climate change more than anything
Mon Feb 11, 2019, 11:48 AM
Feb 2019

I have seen a marked decrease in insects, plenty of mosquitoes after flooding rains, but thats about it.

The_jackalope

(1,660 posts)
7. Little will be done until famine begins to hit the first world
Mon Feb 11, 2019, 12:15 PM
Feb 2019

And of course by then it will be too f'ing late.

Welcome to the Sixth Great Extinction folks. This time we're on the menu.

jcmaine72

(1,773 posts)
13. Kinda ironic that the largest insect decline ever recorded would occur precisely when...
Mon Feb 11, 2019, 02:05 PM
Feb 2019

....the world's biggest cockroach has infested the White House.

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