Have you noticed fewer insects splattered on your windshield during long road trips? Headlines warning of an “Insect Armageddon” and declining insect populations worldwide may not be as alarmist as skeptics think. There is even more evidence that insect populations are indeed plummeting, and it should concern us for the proper functioning of the planet. Here is a look at that evidence, as well as how and why you should take steps to help stop “Insect Armageddon.”
The members of the Entomological Society of Krefeld, Germany were responsible for the global news story a few months ago. They collected insects in 63 nature reserves in and near Krefeld over a period of nearly 30 years. The number of specimens per sample has dropped drastically from the beginning to present.
Entomologists in Australia have noted declines in populations of insects there, especially mosquitoes and certain butterflies. People who breed the spectacular Ulysses Swallowtail for butterfly houses in Australia and other parts of the world have observed declines in survivorship, especially in the second generation of the metallic blue and black butterfly. Extremes in weather, notably drought and excessive heat, have adversely impacted many insect species Down Under.
Canadian scientists studying declining populations of the Whip-poor-will, an insect-eating bird, have concluded that the large flying insects the birds prefer to eat are mostly absent from the diet of the birds today. By analyzing museum specimens dating back decades, they discovered that the birds were healthier than they are now. Large insects accumulate a different type of the element nitrogen than do smaller insects. This nitrogen “fingerprint” transfers over to insect predators, so the scientists can trace differences in the nitrogen “signature” in the birds. Whip-poor-wills are declining an average of 3.5% each year, likely due in part to the decrease in the insects they eat.
Why Is Insect Armageddon a Problem?
Yes, some insects bite us, some carry diseases, and some sting, but when push comes to shove, we could not exist without most “bugs.” They pollinate crops and flowers, they clean up animal waste and dead plants and animals, they feed wildlife from birds to bears, and they control pests like other insects and noxious weeds.
These are but a few “ecosystem services” bugs provide that make life on earth possible. In North America, the Black-capped Chickadee relies on caterpillars to feed their chicks. One pair of chickadees feeds their chicks between 390-560 caterpillars each day, meaning they need 6,000-9,000 caterpillars just to raise a full next from hatchling to fledgling!
We have ironically encouraged the increase of pests like ticks and mosquitoes, while decimating the good ones like bees.
What Is Causing This Decline in Insects?
Ironically, collection of insects by scientists has little or no adverse effect on insect populations. Here are the main causes of this Insect Armageddon:
- Conversion of wild habitat to agriculture, housing, commercial development.
- Global climate change resulting in local weather extremes.
- Continued and increased use of pesticides that kill all insects, not just pests.
- Water pollution that kills many aquatic insects.
- Light pollution that disrupts the reproductive cycles of nocturnal insects.
- Collisions with motor vehicles, especially in rural and wilderness areas.
What Can You Do to Stop Insect Armageddon?
More study is needed to define exactly what is happening, but we can all be aware of this phenomenon, and be mindful of how our personal actions can help or hurt:
- Do not use pesticides in the home, garden, or workplace.
- Recognize that many “weeds” are wildflowers that are food for bees.
- Leave fallen leaves where they land to provide insulating winter cover for insects.
- Landscape with native plants, trees, and shrubs.
- Learn more about insects online, in books, and at museums and nature centers.
You can also support insect conservation by joining the Xerces Society.