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.
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.
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.
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.
Comments:
Lets bring back coal, do away with the EPA, repeal the Clean Air Act, repeal the Clean Water Act, and deny man made climate change.
That should solve these problems.
