Who is the real locust?
By Dale Goodner | 2nd July 2007
A big black insect, two inches long, with intense red eyes, landed on my hand and brazenly buzzed as I was giving a customer her change. It was the “Return To Pimiteoui Pow-wow” and I was collecting admissions. This newly arrived critter made it appear that I was actually trying to hand him to her, along with a couple of dollars. She didn’t seem particularly surprised. “Oh, another of those locusts.”Actually they are seventeen-year periodic cicadas (locusts are grasshoppers). They emerged in June, after 17 years as subterranean larvae, and quickly filled the forest with their frenzied mating, the males trying to out-buzz millions of competitors in order to attract females. Their cacophonous chorus was a true blast from the past after nearly two decades of silence. The last time their buzz filled the air, my college-sophomore son, Chris, was just a toddler, I was working at the Nature Center and walking up Forest Park Drive each day to my bicycle (parked atop the hill), through the droning deafening din, getting the full benefit of their cyclical survival song.
Their long hiatus between hatchings isn’t the only mysterious thing about these amazing cicadas. How do billions of insects get their act together, hatching and burrowing out of the ground as a group, and then even singing as one, their collective voices rising and falling in a regular rhythm?
They filled the woods of Central Illinois this June with their urgent chorus. At the Pow wow at W.H. Sommer Park (June 9th and 10th), they were not only buzzing from the trees, but there was almost no place to escape their errant flights. These huge bugs were everywhere. Wait long enough and one would land on you. People who normally ‘freak out’ over just about any insect, however, seemed to be cool in the midst of the cicada reproductive dance. After all, we now have to wait another 17 years to witness this again.
Because of the vast numbers of emerging cicadas, the ground around the bases of trees was riddled with sizable holes, looking as if an army of horticulturists had been aerating the soil with seven/sixteenths inch drill bits. Their red eyes and black body set them off a little, but their mind boggling numbers, all emerging at once after staying in the larval stage for seventeen years makes them truly unique. Once the entire gang hatches, they have just a few weeks to mate and produce the next generation. The urgency to reproduce is heard in their intense singing.
Even though these critters are often called locusts, they are not at all related. They are periodic cicadas, more closely related to true bugs (such as box elder bugs, or stink bugs, for example). Although they number in the billions, they don’t devastate the land as do true locusts. They don’t feed as adults, just mate, lay eggs, and die. The young attach themselves to tree roots and settle in for 17 years of sap sipping.
Locusts are referred to as grasshoppers until their population density reaches a peak. They form immense swarms and move en masse, apparently in response to environmental stress, such as drought, and lack of food. The result can be as frightening as it is devastating. Perhaps the most well known case occurred in the latter part of the 19th century.
In 1874 the Bronx was annexed by New York City; Levi Strauss and Jacob Davis received a patent for blue jeans with copper rivets (the jeans sold for $13.50/ dozen); the first public zoo in the U.S. opened in Philadelphia; and Robert Frost and Winston Churchill were born. This was also the year Rocky Mountain locusts formed a swarm beyond biblical proportions.
July of 1874 saw what could be the world’s largest swarm of locusts (or anything else) ever. Reports of this swarm which occurred around Wyoming, Colorado, and Nebraska, sound like science fiction.
The sky-blackening swarm covered an area twice the size of Colorado (198,000 square miles). The mass, consisting of some 12.5 trillion Rocky Mountain locusts, probably weighed around 28 million tons. That’s a lot of grasshoppers.
They devoured saddles, gnawed on ax handles and fence posts, ate laundry flapping on the line and chewed the wool right off sheep.
The sky became dark under a blanketing cloud. This cloud measured some 1800 miles long by about 120 miles wide. When it had finally passed over, there was basically nothing left. Crops were completely stripped. According to the Guiness Book of World Records, it was the largest mass migration ever.
It’s been theorized that these locusts were responding to environmental changes caused by European immigrants farming in the central/ northern Rockies region. But that is not likely. As glaciers in the Northern Rockies recede today (in response to global warming), tens of millions of Rocky Mountain locusts, which have been locked in that ice for some 400 years (according to carbon dating) are washing downstream in melt water. Their mass demise far preceded European influences. This could indicate their swarming behavior was cyclical.
Perhaps drought triggered this mass migration. This makes some sense. When the local ecosystem can no longer sustain a population of critters, there are few choices. Starve or leave. It is ironic that within a couple decades the Rocky Mountain Locust, whose population had been so overwhelming, passed into (bad) memory. Attempts have been made in recent years to find these grasshoppers in isolated locations in the northern Rockies and western Canada, but to no avail. They appear to be extinct.
It’s possible to see a parallel between some human behaviors in recent centuries and the swarming behavior of locusts. Our species has done countless mass migrations in response to drought and food shortage, but there are other incentives, such as political or religious hostility and war.
Consider just a couple of the monumental impacts we’ve had on what was pristine landscape:
· The entire tall grass prairie of the American Midwest was destroyed and converted to farming within a handful of decades.
· All the old growth forests of North America were consumed with no regard for the ecological implications. Remnants are few and far between.
· 60 million American bison were hunted essentially to extinction just after the Civil War. Only a couple hundred stragglers in Yellowstone were inadvertently left. From this meager number came today’s bison.
· Petroleum has been extracted from throughout the world and burned up within a century to such a degree as to threaten the climate of the entire planet. Ironically the resulting warming is melting glaciers and releasing the newly thawed bodies of centuries old Rocky Mountain locusts.
· The gold rush of 1849 saw the Sierra Nevada range torn up for gold, stripped of trees, and native cultures were devastated. The scars are still visible.
· Even the oceans are not exempt. Fisheries have been depleted throughout the world.
It has taken an immense number of people to do such a thorough job of exploitation. Conversely it will take a coordinated effort on the part of multitudes to restore ecological integrity and put us on a sustainable track.
Locusts impose their impressive appetites upon the landscape, stripping anything edible that’s in their path. They leave devastation in their wake. In the case of Rocky Mountain locusts, this behavior undoubtedly contributed to their own demise.
Locusts and cicadas are of similar size and shape, they swarm in vast numbers, but the similarity ends there. Cicadas represent an ability to use their numbers for survival. There’s a lesson here for us. Perhaps like the cicadas whose billions of individuals are able to act and even sing together, we could coordinate and plan. Our consumption of what we call resources could be tempered. Uses could be cyclical. We have to allow the land organism time to recover from our demands. This will require a non locust-like attitude and approach. Our long term goal has to be sustainability.
Well, which is? Locust or Cicada?
November 12th, 2008 at 10:29 pm
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