Apparently, the global political chaos we are experiencing is only one of humanity’s problems–and perhaps not the most threatening.
Around the globe, scientists are getting hints that all is not well in the world of insects. Increasingly, reports are trickling in of unsettling changes in populations of not only butterflies and bees, but of far less charismatic bugs and beetles as well. Most recently, a research team from the U.S. and Mexico reported a startling decline between 1976 and 2013 in the weight of insects and other arthropods collected at select sites in Puerto Rico.
Some have called the apparent trend an insect Armageddon. Although the picture is not in crisp enough focus yet to say if that’s hyperbolic, enough is clear to compel many to call for full-scale efforts to learn more and act as appropriate.
Insects have always outnumbered other life forms–by far. According to scientists, nearly a million species have been described to date. (That compares with 5,416 mammals.) Entomologists suspect there could be two to 30 times as many actually out there.
Or were. And a steep decline would have significant consequences for humans.
Insects pollinate a spectrum of plants, including many of those that humans rely on for food. They also are key players in other important jobs including breaking dead things down into the building blocks for new life, controlling weeds and providing raw materials for medicines. And they provide sustenance for a spectrum of other animals—in fact, the Puerto Rico study showed a decline in density of insect-eating frogs, birds and lizards that paralleled the insect nosedive.
All told, insects provide at least US$57 billion in services to the U.S. economy each year.
How steep is the decline? The Post reports
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 article quoted two scientists who had worked in the Puerto Rico rainforest forty years ago, about what they found when they recently returned.
What the scientists did not see on their return troubled them. “Boy, it was immediately obvious when we went into that forest,” Lister said. Fewer birds flitted overhead. The butterflies, once abundant, had all but vanished.
Other research has confirmed the loss of insects–and the dramatic reductions of insect-eating frogs and birds.
Lister and Garcia attribute this crash to climate. In the same 40-year period as the arthropod crash, the average high temperature in the rain forest increased by 4 degrees Fahrenheit. The temperatures in the tropics stick to a narrow band. The invertebrates that live there, likewise, are adapted to these temperatures and fare poorly outside them; bugs cannot regulate their internal heat.
Pesticides and habitat loss are also culprits.
Most of us of a “certain age” can remember catching fireflies–lightning bugs–as children. We recall having to clean smashed bugs off windshields, and seeing swarms of insects around streetlights. I haven’t seen a firefly in years–and my windshield stays pristine even on long drives. Last summer, I didn’t have a single mosquito bite, although for years I was sure mosquitos found something about me irresistible.
Nice as it is not to spend summers scratching, the implications for the ecosystem are frightening.
I don’t know what the solution is, but I do know that this really isn’t a good time to be governed by aggressively ignorant people.