SEVERE WX : Red Flag Warning View Alerts
STREAMING NOW: Watch Now

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

We may lose all insects within 100 years if we don't act now to prevent damage to our ecosystems, says the lead author of a new global review.

Posted: Feb 11, 2019 7:22 AM


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.

Its lead author, Francisco Sanchez-Bayo, of the School of Life and Environmental Sciences at the University of Sydney, called the study the first truly global examination of the issue.

While the focus in the past has been on the decline in vertebrate animal biodiversity, this study stressed the importance of insect life on interconnected ecosystems and the food chain. Bugs make up around 70% of all animal species.

The repercussions of insect extinction would be "catastrophic to say the least," according to the report, as insects have been at "the structural and functional base of many of the world's ecosystems since their rise ... almost 400 million years ago."

Key causes of the decline included "habitat loss and conversion to intensive agriculture and urbanization," pollution, particularly from pesticides and fertilizers, as well as biological factors, such as "pathogens and introduced species" and climate change.

While large numbers of specialist insects, which fill a specific ecological niche, and general insects were declining, a small group of adaptable insects were seeing their numbers rise -- but nowhere near enough to arrest the decline, the report found.

Small creatures that run the world

Don Sands, an entomologist and retired Commonwealth Scientific and Industrial Research Organization scientist, said he agreed "entirely" that the "bottom-up" effects of insect loss were serious.

"If we don't have insects as moderators of other pest populations, we have insect populations that flare up and ruin crops and make them difficult to grow," he said.

He added that the ecosystem at this level has "to be in balance. That's the bottom layer and unless we address it all our lives could be impacted immeasurably.

"(Insects are) the small creatures that run the world," he said.

Reports of insect decline are not new: researchers have been warning of the phenomenon and its impact for years.

Last year, one study found that flying insect populations in German nature reserves declined by more than 75% over the duration of a 27-year study, meaning that the die-off is happening even beyond areas affected by human activity.

"These are not agricultural areas, these are locations meant to preserve biodiversity, but still we see the insects slipping out of our hands," said that report's co-author, Caspar Hallman.

Birds eating birds

Species that rely on insects as their food source -- and the predators higher up the food chain which eat those species -- were likely to suffer from these declines, according to the scientists. The pollination of both crops and wild plants would also be affected, along with nutrient cycling in the soil.

Indeed, "ecosystem services provided by wild insects have been estimated at $57 billion annually in the USA," according to an earlier study.

Some 80% of wild plants use insects for pollination while 60% of birds rely on insects as a food source, according to the study. Sands said an immediate danger of the insect decline was the loss of insectivorous birds, and the risk of larger birds turning from eating insects to eating each other.

In his native Australia, "birds that are running out of insect food are turning on each other," he said, adding that this is likely a global phenomenon.

Radical action needed

The report's authors called for radical and immediate action.

"Because insects constitute the world's most abundant and (species-diverse) animal group and provide critical services within ecosystems, such events cannot be ignored and should prompt decisive action to avert a catastrophic collapse of nature's ecosystems," they wrote.

They suggested overhauling existing agricultural methods, "in particular a serious reduction in pesticide usage and its substitution with more sustainable, ecologically-based practices."

"The conclusion is clear: unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades," they concluded.

Oregon Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 19366

Reported Deaths: 328
CountyConfirmedDeaths
Multnomah449793
Washington284923
Marion269268
Umatilla206024
Clackamas142136
Malheur67610
Deschutes5408
Lane5233
Lincoln3959
Jackson3941
Union3882
Yamhill38611
Jefferson3113
Morrow3051
Polk29612
Linn25410
Klamath1961
Wasco1703
Hood River1690
Benton1576
Douglas1341
Josephine1071
Coos850
Clatsop820
Columbia790
Crook431
Baker330
Lake320
Tillamook300
Wallowa191
Sherman150
Curry140
Harney80
Gilliam40
Grant20
Unassigned00
Wheeler00

California Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 516851

Reported Deaths: 9441
CountyConfirmedDeaths
Los Angeles1938774702
Orange37813651
Riverside37011695
San Bernardino33432418
San Diego29883565
Kern20651144
Fresno15083138
San Joaquin11885180
Alameda11524189
Santa Clara10794191
Sacramento10122145
Tulare9745189
Imperial9448222
Stanislaus9221112
Contra Costa8033127
Ventura734476
San Francisco691661
Santa Barbara616760
San Mateo5683119
Marin509270
Monterey492430
Kings445356
Merced428550
Solano361137
Sonoma311339
Madera194330
Placer192516
San Luis Obispo190216
Yolo157242
Santa Cruz11524
Butte9417
Napa8888
Sutter7976
San Benito6474
El Dorado6371
Lassen6260
Yuba5024
Shasta3909
Glenn3321
Colusa3314
Mendocino3229
Nevada2991
Tehama2341
Humboldt2334
Lake2081
Mono1451
Tuolumne1412
Amador1260
Calaveras1251
Del Norte880
Siskiyou730
Inyo611
Mariposa572
Plumas330
Trinity50
Alpine20
Modoc20
Sierra20
Unassigned00
Medford
Clear
81° wxIcon
Hi: 95° Lo: 62°
Feels Like: 81°
Brookings
Overcast
58° wxIcon
Hi: 66° Lo: 54°
Feels Like: 58°
Crater Lake
Clear
77° wxIcon
Hi: 87° Lo: 56°
Feels Like: 78°
Grants Pass
Clear
77° wxIcon
Hi: 92° Lo: 60°
Feels Like: 79°
Klamath Falls
Clear
77° wxIcon
Hi: 89° Lo: 52°
Feels Like: 78°
Thunderstorm chances ahead
KDRV Radar
KDRV Fire Danger
KDRV Weather Cam

Community Events