What a Pandemic Can Teach Us about the Demise of Insect Biodiversity
By Jerry Jung | June 17, 2020
Co-founder’s note: “I authored this timely essay. It was published by the Washington Times. Although it does not address the absurdity of biofuel subsidies, it explains another reason that corn production in excess of our needs is so detrimental to biodiversity.”
It has been over a century since so many people have been informed about the spread of a contagious disease. Concepts such as herd immunity, social distancing and how airborne pathogens are spread have become the centerpiece of numerous blogs, articles and conversations.
Perhaps a better-informed public can now appreciate what is happening to the global ecosystem. As numerous scientific and popular articles attest, insect populations are in steep decline. I’ve experienced this firsthand on my hobby farm in central Michigan when monarch butterflies stopped arriving on their multi-generation migration from Mexico. Insect populations, especially migrating insect populations that comprise larger flying insects, have been decimated in the past 10 to 20 years. More than 40% of insect species are in decline and a third are endangered. Monarch populations are off over 90%. Predictably, insect-eating birds and bats are in steep decline. Some scientists speculate that bats played a role in the spread of the Covid-19 virus. When the fierce immune systems of these flying mammals are stressed, they can become perfect carriers for dangerous viruses. You’d be stressed also if you didn’t have anything to eat!
The New York Times recently published an article, What’s happening to the Monarch Butterfly Population? “Something is going on in early spring” and scientists aren’t sure what it is, the article says. Well, I believe I know what the problem is and hope that scientists and policy makers will embrace my explanation.
Bacillus thuringiensis (Bt) is a bacterium that naturally occurs in certain soils. If Bt enters the digestive tract of many species of insect larvae it multiplies and kills or impairs them. It is especially lethal to moth and butterfly larva known to most of us as caterpillars.
The European earworm is a moth that lays eggs on ears of corn that the young larva feast on. Many of us who are older remember when it was not unusual to see damaged kernels left near the top of an ear of sweet corn. The reason that we no longer see this is because, like the monarch, the moth that harms corn is also in decline. Why you might wonder…
In the early 1990’s genetic scientists successfully inserted the Bt genome into corn. Inserting Bt into crops is scary for several reasons: First, consider that there are over 100,000,000 acres of corn planted in the U.S. on an annual basis. Second, consider that the corn is wind pollinated and that the pollen itself contains the Bt genetic sequence. Third, the pollen can blow 600 yards or more from its source. When it lands on a food source, milkweed in the case of monarch butterflies, it kills the caterpillar. The coronavirus jumped from one member of the mammal family to another. Is it possible that Bt genes jump from corn to other plants in the grass family?
The data documenting the decline of the monarch correlates well with the introduction of Bt corn. There are data driven studies that confirm that Bt kills monarchs. To these I wish to add anecdotal evidence. While gardening 8 years ago, I saw a Monarch alight on top of a tassel of corn. (From an evolutionary perspective, the butterfly proboscis preceded nectar bearing flowers.) Six years ago, while visiting acreage I lease to a farmer who grows corn, I saw impaired monarchs that were half sized and flew awkwardly.
The principles of herd immunity dictate that coronavirus will diminish as more people contract the disease and die or develop immunity. The concept is not unlike predator-prey cycles whereby predator populations expand when prey is abundant and decline when prey is scarce. This is how nature reaches an equilibrium. Unfortunately for insects (and ultimately for us) there are over 200 strains of Bt so developing immunity to all of them is unlikely. Furthermore, the production of Bt spores is not coupled to the availability of a host as is the case with other viruses and bacterium. It is produced by an array of crops without any regard to the scarcity of insect carriers. Without ecological equilibrium, the prospect of extinction becomes very real.
Genetically Modified Organisms (GMOs) can be a good thing when they improve a crop’s hardiness, yield or nutritional value. They are not a good thing when they spew forth self-replicating bio-toxins.