Chipmunks, acorns and Monarch butterflies

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When you hear a low-pitched ‘chuck, chuck’ sound over and over in a wood lot or in a shaded place around your house, it’s not an insect, frog, or woodchuck, but it’s the call of an eastern chipmunk, and you’ll know that October has arrived. October and occasionally  early November are the only times of the year when chipmunks are heard. Neither I nor any other biologist knows why the little critters restrict their vocalizations to early fall or the significance of their calls. They may be mating calls, territorial warning calls, or both. Perhaps some day I’ll learn.
Another sound beginning in October of some years the plop, plop sound of white oak acorns falling. Three or four years ago, white oak acorns fell in abundance. I could have picked up several pounds that fell on my deck from the overhanging trees. In September of this year, I could see no acorns on the trees, and I feared that the oaks would again fail to produce a crop. But in October, they produced another bumper crop. So the squirrels, deer, turkeys, and any other critters that rely heavily on the acorns should be glad for this year’s bounty.
In past columns I have lamented the decline of our state’s official insect, the monarch butterfly.
Monarchs deposit their eggs on milkweeds, on which the larvae feed prior to pupating. Those emerging west of the Rocky Mountains overwinter in California. The eastern populations in the U. S. and Canada make an epic journey to a mountainous area in central Mexico, an astonishing flight of up to 3,000 miles. The beautiful orange, black, and white wings of monarchs warn would-be predators that the insects are foul-tasting and poisonous to eat. Viceroy butterflies are similarly colored and are also left alone by predators.
Monarchs underwent a sharp decline several decades ago. Illegal harvesting of trees in their Mexican refuge is believed to be partially responsible, but a decline in milkweeds in the U.S. and Canada is according to most biologists the most important factor. The herbicide Roundup, produced by Monsanto and “Roundup Ready”  genetically modified seeds, which produce soybeans, cotton, and corn resistant to Roundup, enabled farmers to use Roundup to kill weeds, including milkweeds, in and around their fields. Thus, milkweeds took a hit as did monarch butterflies in places where Roundup was applied or drifted from such places.
But the active ingredient of Roundup is the chemical glyphosate. The “JereBeasleyReport” (Nov. edition) states that 37 lawsuits nationwide have been filed alleging that glyphosate can cause the cancer Non-Hodgkin’s Lymphoma and that Monsanto failed to warn consumers and  regulators about the alleged risks.
Roundup is said to be the most widely used agricultural chemical in the world. Several European countries have banned its usage. Meanwhile, people concerned about monarch butterflies have begun planting milkweeds in places where they will not be killed by Roundup. The efforts have apparently met with some success. In addition, authorities in Mexico are making efforts to stop illegal harvesting of trees in the insects’ overwintering habitat. Observers report that in recent years the numbers of monarchs seem to be increasing.
The aforementioned JereBeasey report says it expects the number of lawsuits about the alleged risks of glyphosate to increase as more people realize the possible harm it does to farmers, landscapers, gardeners and others regularly and consistently exposed to the herbicide.
Bob Mount is a Professor Emeritus with the Department of Zoology and Entomology at Auburn University. He is also chairman of the Opelika Order of Geezers, well-known local think tank and political clearing house. He writes about birds, snakes, turtles, bugs and assorted conservation topics.

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