SOURCE: Washington Post
DATE: October 15, 2018
SNIP: Insects around the world are in a crisis, according to a small but growing number of long-term studies showing dramatic declines in invertebrate populations. A new report suggests that the problem is more widespread than scientists realized. Huge numbers of bugs have been lost in a pristine national forest in Puerto Rico, the study found, and the forest’s insect-eating animals have gone missing, too.
In 2014, an international team of biologists estimated that, in the past 35 years, the abundance of invertebrates such as beetles and bees had decreased by 45 percent. In places where long-term insect data are available, mainly in Europe, insect numbers are plummeting. A study last year showed a 76 percent decrease in flying insects in the past few decades in German nature preserves.
The latest report, published Monday in the Proceedings of the National Academy of Sciences, shows that this startling loss of insect abundance extends to the Americas. The study’s authors implicate climate change in the loss of tropical invertebrates.
“This study in PNAS is a real wake-up call — a clarion call — that the phenomenon could be much, much bigger, and across many more ecosystems,” said David Wagner, an expert in invertebrate conservation at the University of Connecticut who was not involved with this research. He added: “This is one of the most disturbing articles I have ever read.”
“Holy crap,” Wagner said of the 60-fold loss.
The food web appears to have been obliterated from the bottom. It’s credible that the authors link the cascade to arthropod loss, Schowalter said, because “you have all these different taxa showing the same trends — the insectivorous birds, frogs and lizards — but you don’t see those among seed-feeding birds.”
“It’s bewildering, and I’m scared to death that it’s actually death by a thousand cuts,” Wagner said.
“Unfortunately, we have deaf ears in Washington,” Schowalter said. But those ears will listen at some point, he said, because our food supply will be in jeopardy.
The loss of insects and arthropods could further rend the rain forest’s food web, Lister warned, causing plant species to go extinct without pollinators. “If the tropical forests go it will be yet another catastrophic failure of the whole Earth system,” he said, “that will feed back on human beings in an almost unimaginable way.”