WHO KNEW that We Can Help Reverse the Decline of Our Pollinators?
The Entomological Society Krefeld, a volunteer group in Germany, has monitored insects regularly since 1905. Their methods and sample plots were the same every year. In 2017, they reported that insect counts had declined by 75% in just 30 years. A worldwide survey of studies of insect populations confirmed a loss of at least 40%.
Some of us remember when car windshields were regularly coated with masses of dead bugs. It isn’t that improved car design led to fewer squished bugs; there really were many more bugs back then. In the wake of this loss, populations of birds, which need insect larvae to feed their young, and other creatures have declined too.
E.O. Wilson said best: “If all mankind were to disappear, the world would regenerate back to the rich state of equilibrium that existed ten thousand years ago. If insects were to vanish, the environment would collapse into chaos.”
WHY THE DECLINE?
HABITAT LOSS: Human development has fragmented land into smaller lots, replaced vegetation with buildings and pavement, and displaced native plants with species that native insects are not adapted to. Furthermore, industrial-scale agriculture, with huge fields, monoculture and little crop rotation, leaves few wild spaces and hedgerows for insects to feed and nest in. Ironically, many large farms rent truckloads of non-native honey-bee hives to make up for the loss of native insects.
INVADERS: Non-native insects and diseases have destroyed habitat (think hemlock wooly adelgid, emerald ash borer and chestnut blight) as have non-native plants that out-compete native plants and cover a forest floor (think buckthorn, garlic mustard or Japanese barberry). The invaders multiply unchecked by the natural controls found in their places of origin.
PESTICIDES: Two new products were approved for use in the 1990s: neonicotinoid chemicals (a nerve toxin) and herbicide-resistant GMO (genetically modified) crops. GMO crops enable weeding by chemical sprays that can drift and kill nearby pollinator plants. The seeds of certain crops such as corn are coated with systemic neonicotinoid pesticides that contaminate all parts of the plants – so any insect that eats a leaf or pollen will be affected by the poison.
These chemicals, ‘neonics’, Imidacloprid Thiamethoxam, Dinotefuran, Acetamiprid and Clothianidin, are offered to the public under trademarks that mask their hazards. To name just a few: Safari, Green-Light, Flagship, Merit, Meridian, Once-a-Year, Bug B Gon, Arena, Aloft, Bandit, Criterion, so look for them in the fine print on the labels of lawn or garden products. Further, these neural toxins are water soluble and break down slowly so they easily get into streams to harm aquatic insects. The USGS has found half our streams are contaminated with the stuff.
HOW CAN WE REVERSE THIS LOSS?
The decline in insects is often called the “Sixth Extinction” and we can do something about it: Consider inducements that our lawns and gardens need lots of chemicals and frequent mowing and be sure to read the labels. Throw out your bug-zappers! Ask your representatives in Congress to get neonicotinoids forbidden or greatly restricted, as has happened in other countries. Get more information about these chemicals.
AND on your own turf, install pollinator gardens, as described here last week. An exuberant pollinator garden is much more interesting than a patch of mowed lawn!