Grasshoppers are perhaps best known for the occasions throughout history when an enormous congregation of these insects—a “plague of locusts”—would assemble and rove a region to feed. These swarms, which sometimes covered tens of thousands of square miles or more, often decimated crops, darkened the sky, and, on occasion, resulted in catastrophic famine among human settlements in various parts of the world.
The largest “plague of locusts” in the United States occurred during the mid-1870s in the Great Plains. The Rocky Mountain Locust (Melanoplus spretus), a grasshopper of prairies in the American west, had a range that extended east into New England, possibly settling there on lands cleared for farming. Rocky Mountain Locusts, aside from their native habitat on grasslands, apparently thrived on fields planted with warm-season crops. Like most grasshoppers, they fed and developed most vigorously during periods of dry, hot weather. With plenty of vegetative matter to consume during periods of scorching temperatures, the stage was set for populations of these insects to explode in agricultural areas, then take wing in search of more forage. Plagues struck parts of northern New England as early as the mid-1700s and were numerous in various states in the Great Plains through the middle of the 1800s. The big ones hit between 1873 and 1877 when swarms numbering as many as trillions of grasshoppers did $200 million in crop damage and caused a famine so severe that many farmers abandoned the westward migration. To prevent recurrent outbreaks of locust plagues and famine, experts suggested planting more cool-season grains like winter wheat, a crop which could mature and be harvested before the grasshoppers had a chance to cause any significant damage. In the years that followed, and as prairies gave way to the expansive agricultural lands that presently cover most of the Rocky Mountain Locust’s former range, the grasshopper began to disappear. By the early years of the twentieth century, the species was extinct. No one was quite certain why, and the precise cause is still a topic of debate to this day. Conversion of nearly all of its native habitat to cropland and grazing acreage seems to be the most likely culprit.
The critically endangered Eskimo Curlew (Numenius borealis), a species not photographed since 1962 and not confirmed since 1963, fed on Rocky Mountain Locusts during its spring migration through the Great Plains. Excessive hunting and conversion of grasslands to agriculture are believed responsible for the bird’s demise. (United States Fish and Wildlife Service image by Christina Nelson)
In the Mid-Atlantic States, the mosaic of the landscape—farmland interspersed with a mix of forest and disturbed urban/suburban lots—prevents grasshoppers from reaching the densities from which swarms arise. In the years since the implementation of “Green Revolution” farming practices, numbers of grasshoppers in our region have declined. Systemic insecticides including neonicotinoids keep grasshoppers and other insects from munching on warm-season crops like corn and soybeans. And herbicides including 2,4-D (2,4-Dichlorophenoxyacetic acid) have, in effect, become the equivalent of insecticides, eliminating broadleaf food plants from the pasturelands and hayfields where grasshoppers once fed and reproduced in abundance. As a result, few of the approximately three dozen species of grasshoppers with ranges that include the Lower Susquehanna River Watershed are common here. Those that still thrive are largely adapted to roadsides, waste ground, and small clearings where native and some non-native plants make up their diet.
Here’s a look at four species of grasshoppers you’re likely to find in disturbed habitats throughout our region. Each remains common in relatively pesticide-free spaces with stands of dense grasses and broadleaf plants nearby.
CAROLINA GRASSHOPPER
Dissosteira carolina
The Carolina Grasshopper, also known as the Carolina Locust or Quaker, is one of the band-winged grasshoppers. It is commonly found along roadsides and on other bare ground near stands of tall grass and broadleaf plants.The Carolina Grasshopper is variable in color, ranging from very dark brown……to a rich tan or khaki shade. These earth-tone colors provide the insect with effective camouflage while spending time on the ground.The Carolina Grasshopper is most readily detected and identified when it flies. The colors of the wings resemble those of the Mourning Cloak butterfly.Carolina Grasshoppers are among the preferred victims of Great Black Wasps (Sphex pensylvanicus). A female wasp stings the grasshopper to paralyze it, then drags it away to one of numerous cells in an underground burrow where she lays an egg on it. The body of the disabled grasshopper then provides nourishment for the larval wasp.
DIFFERENTIAL GRASSHOPPER
Melanoplus differentialis
Differential Grasshopper nymph with small “fairy wings”.An adult Differential Grasshopper with fully developed wings.
TWO-STRIPED GRASSHOPPER
Melanoplus bivittatus
An early-stage Two-striped Grasshopper nymph.A Two-striped Grasshopper nymph in a later stage.An adult Two-striped Grasshopper.An adult Two-striped Grasshopper. Note the pale stripe originating at each eye and joining near the posterior end of the wings to form a V-shaped pattern.A female Two-striped Grasshopper.
RED-LEGGED GRASSHOPPER
Melanoplus femurrubrum
The Red-legged Grasshopper may currently be our most abundant and widespread species.A Red-legged Grasshopper hiding in dense urban vegetation.A male Red-legged Grasshopper.A female Red-legged Grasshopper.
Protein-rich grasshoppers are an important late-summer, early-fall food source for birds. The absence of these insects has forced many species of breeding birds to abandon farmland or, in some cases, disappear altogether.
During the mid-twentieth century, the Cattle Egret (Bubulcus ibis), a notoriously nomadic species, transited the Atlantic from Africa to colonize the Americas…and they did it without any direct assistance from humans. During the 1970s and early 1980s, a nesting population of Cattle Egrets on river islands adjacent to the Susquehanna’s Conejohela Flats off Washington Boro was the largest inland rookery in the northeastern United States. The Lancaster County Bird Club censused the birds each August and found peak numbers in 1981 (7,580). During their years of abundance, V-shaped flocks of Cattle Egrets from the rookery islands ventured into grazing lands throughout portions of Lancaster, York, Dauphin, and Lebanon Counties to hunt grasshoppers. These daily flights were a familiar summertime sight for nearly two decades. Then, in the early 1980s, reductions in pastureland acreage and plummeting grasshopper numbers quickly took their toll. By 1988, the rookery was abandoned. The Cattle Egrets had moved on. (Vintage 33 mm image)During the summer and early fall, juvenile and adult Ring-necked Pheasants feed heavily on grasshoppers. Earlier and more frequent mowing along with declining numbers of grasshoppers on farmlands due to an increase in pesticide use were factors contributing to the crash of the pheasant population in the early 1980s.To the delight of Wild Turkeys, each of the four species of grasshoppers shown above frequents clearings and roadsides adjacent to forest areas. While changes in grasshopper distribution have been detrimental to populations of birds like pheasants, they’ve created a feeding bonanza for turkeys.Wild Turkeys feeding on an abundance of grasshoppers along a forest road.An American Kestrel feeds on a grasshopper while ignoring the abundance of Spotted Lanternflies swarming the adjacent utility pole. In Susquehanna valley farmlands, grasshopper and kestrel numbers are down. Lanternflies, on the other hand, have got it made.Maintaining areas bordering roads, forests, wetlands, farmlands, and human development in a state of early succession can provide and ideal mix of mature grasses and broadleaf plants for grasshoppers, pollinators, birds, and other wildlife.
Spectacular annual wildflowers in bloom along a border separating a fitness trail from a field of maize in Hershey, Pennsylvania. Such plantings can provide vital habitat for pollinators that otherwise find no sustenance among monocultures of neonicotinoid-treated crops like corn and soybeans.
After nearly a full week of record-breaking cold, including two nights with a widespread freeze, warm weather has returned. Today, for the first time this year, the temperature was above eighty degrees Fahrenheit throughout the lower Susquehanna region. Not only can the growing season now resume, but the northward movement of Neotropical birds can again take flight—much to our delight.
A rainy day on Friday, May 8, preceded the arrival of a cold arctic air mass in the eastern United States. It initiated a sustained layover for many migrating birds.
Bobolinks (Dolichonyx oryzivorus) in flocks of as many as fifty birds gathered in weedy meadows and alfalfa fields for the week.A Bobolink sheltering in a field of Sweet Vernal Grass (Anthoxanthum odoratum) during the rain on Friday, May 8th.Two of seven Solitary Sandpipers (Tringa solitaria) in a wet field on Friday, May 8. Not-so-solitary after all.Grounded by inclement weather, Rose-breasted Grosbeaks (Pheucticus ludovicianus) made visits to suburban bird feeders in the lower Susquehanna valley. (Charles A. Fox image)
Freeze warnings were issued for five of the next six mornings. The nocturnal flights of migrating birds, most of them consisting of Neotropical species by now, appeared to be impacted. Even on clear moonlit nights, these birds wisely remained grounded. Unlike the more hardy species that moved north during the preceding weeks, Neotropical birds rely heavily on insects as a food source. For them, burning excessive energy by flying through cold air into areas that may be void of food upon arrival could be a death sentence. So they wait.
A freeze warning was issued for Saturday morning, May 9, in the counties colored dark blue on the map. (NOAA/National Weather Service image)This radar image from 3:28 A.M. Saturday morning, May 9, indicates a minor movement of birds in the Great Plains, but there are no notable returns shown around weather radar sites in the freeze area, including the lower Susquehanna valley. (NOAA/National Weather Service image)To avoid the cold wind on Saturday, May 9, this Veery was staying low to the ground within a thicket of shrubs in the forest.This Black-throated Blue Warbler avoided the treetops and spent time in the woodland understory. He sang not a note. With birds conserving energy for the cold night(s) ahead, it was uncharacteristically quiet for the second Saturday in May.A secretive Northern Waterthrush (Parkesia noveboracensis) remained in a wetland thicket.A Scarlet Tanager (Piranga olivacea) tucks his bill beneath a wing and fluffs-up to fight off the cold during a brief May 9th snow flurry.In open country, gusty winds kept Eastern Kingbirds, a species of flycatcher, near the ground in search of the insects they need to sustain them.Horned Larks are one of the few birds that attempt to scratch out an existence in cultivated fields. The application of herbicides and the use of systemic insecticides (including neonicotinoids) eliminates nearly all weed seeds and insects in land subjected to high-intensity farming. For most birds, including Neotropical migrants, cropland in the lower Susquehanna valley has become a dead zone. Birds and other animals might visit, but they really don’t “live” there anymore.Unable to find flying insects over upland fields during the cold snap, swallows concentrated over bodies of water to feed. Some Tree Swallows may have abandoned their nests to survive this week’s cold. Fragmentation of habitats in the lower Susquehanna valley reduces the abundance and diversity of natural food sources for wildlife. For birds like swallows, events like late-season freezes, heat waves, or droughts can easily disrupt their limited food supply and cause brood failure.For this Barn Swallow, attempting to hunt insects above the warm pavement of a roadway had fatal consequences.Another freeze warning was issued for Sunday morning, May 10, in the counties colored dark blue on this map. (NOAA/National Weather Service image)This radar image from 4:58 A.M. Sunday morning, May 10, again indicates the absence of a flight of migrating birds in the area subjected to freezing temperatures. Unlike migrants earlier in the season, the Neotropical species that move north during the May exodus appear unwilling to resume their trek during freezing weather. (NOAA/National Weather Service image)On Sunday evening, May 10, a liftoff of nocturnal migrants is indicated around radar sites along the Atlantic Coastal Plain and, to a lesser degree, in central Pennsylvania. The approaching rain and yet another cold front quickly grounded this flight.After a one day respite, yet another freeze warning was issued for Tuesday morning, May 12. (NOAA/National Weather Service image)And again, no flight in the freeze area. (NOAA/National Weather Service image)The freeze warning for Wednesday morning, May 13. (NOAA/National Weather Service image)And the nocturnal flight: heavy in the Mississippi valley and minimal in the freeze area. (NOAA/National Weather Service image)The freeze on Thursday morning, May 14. (NOAA/National Weather Service image)At 3:08 A.M. on May 14th, a flight is indicated streaming north through central Texas and dispersing into the eastern half of the United States, but not progressing into New England. (NOAA/National Weather Service image)The flight at eight minutes after midnight this morning. Note the stormy cold front diving southeast across the upper Mississippi valley. As is often the case, the concentration of migrating birds is densest in the warm air ahead of the front. (NOAA/National Weather Service image)
Today throughout the lower Susquehanna region, bird songs again fill the air and it seems to be mid-May as we remember it. The flights have resumed.
Indigo Bunting numbers are increasing as breeding populations arrive and migrants continue through. Look for them in thickets along utility and railroad right-of-ways.Common Yellowthroats and other colorful warblers are among the May migrants currently resuming their northward flights.The echoes of the songs of tropical birds are beginning to fill the forests of the lower Susquehanna watershed. The flute-like harmonies of the Wood Thrush are among the most impressive.Ovenbirds are ground-nesting warblers with a surprisingly explosive song for their size. Many arrived within the last two days to stake out a territory for breeding. Listen for “teacher-teacher-teacher” emanating from a woodland near you.
It’s sprayed with herbicides. It’s mowed and mangled. It’s ground to shreds with noisy weed-trimmers. It’s scorned and maligned. It’s been targeted for elimination by some governments because it’s undesirable and “noxious”. And it has that four letter word in its name which dooms the fate of any plant that possesses it. It’s the Common Milkweed, and it’s the center of activity in my garden at this time of year. Yep, I said milk-WEED.
Now, you need to understand that my garden is small—less than 2,500 square feet. There is no lawn, and there will be no lawn. I’ll have nothing to do with the lawn nonsense. Those of you who know me, know that the lawn, or anything that looks like lawn, and I are through.
Anyway, most of the plants in the garden are native species. There are trees, numerous shrubs, some water features with aquatic plants, and filling the sunny margins is a mix of native grassland plants including Common Milkweed. The unusually wet growing season in 2018 has been very kind to these plants. They are still very green and lush. And the animals that rely on them are having a banner year. Have a look…
The flowers of the Common Milkweed were exceptionally fragrant this year. At their peak in early June, their hyacinth-or lilac-like aroma was so prevalent, it drifted into the house and overwhelmed the stink of the neighbor’s filthy dumpster that he had placed 12 feet away from my walls (100 feet from his).Common Milkweed attracts a pollinating Greenbottle Fly (Lucilia species). The dumpster attracts the invasive House Fly (Musca domestica), carrier of dysentery, typhoid, and other wonderful diseases. Are you following this? Remember as we proceed, milkweed is noxious.Busy Eastern Carpenter Bees (Xylocopa virginica) load up with pollen from the flowers of the Common Milkweed.A Red Milkweed Beetle (Tetraopes tetrophthalmus) munches on a tender fresh Common Milkweed leaf in mid-June.Following the pollination of the flowers, seed pods will begin to grow. I trim these off the plants. The removal of the extra weight allows most of the stems to remain erect through stormy weather. You’ll still get new plants from underground runners. As you may have guessed, I’m trying to keep these plants upright and strong to host Monarch butterfly larvae.
I’ve planted a variety of native grassland species to help support the milkweed structurally and to provide a more complete habitat for Monarch butterflies and other native insects. This year, these plants are exceptionally colorful for late-August due to the abundance of rain. The warm season grasses shown below are the four primary species found in the American tall-grass prairies and elsewhere.
Big Bluestem, a native warm-season grass in flower.Little Bluestem (Schizachyrium scoparium “Fort Indiantown Gap”) in flower. This variety grows on the tank range at the military base where the armored vehicles and prescribed burns substitute for the herd animals and fires of the prairie to prevent succession and allow it to thrive.Partridge Pea can tolerate sandy soil and is a host plant for vagrant Cloudless Sulphur butterflies.Black-eyed Susan (Rudbeckia hirta) is a popular native grassland wildflower.Indiangrass (Sorghastrum nutans) in flower. This and the other native plants shown here are available as seed from Ernst Seed Company in Meadville (PA). They have an unbelievably large selection of indigenous species. You can plant a small plot or acres and acres using really good mixes blended for purposes ranging from reclaiming pipeline right-of-ways and strip mines to naturalizing backyard gardens.A Red Admiral (Vanessa atalanta) butterfly, a migratory species like the Monarch, on Purple Coneflower (Echinacea purpurea). Yes, it is that Echinacea.
There was Monarch activity in the garden today like I’ve never seen before—and it revolved around milkweed and the companion plants.
A female Monarch laying eggs on a Common Milkweed leaf.A third instar Monarch caterpillar with Oleander Aphids (Aphis nerii) on a Common Milkweed leaf. Both of these insect species absorb toxins from the milkweed which makes them distasteful to predators.Fifth instar (left and center) and fourth instar (right) monarch caterpillars devour a Common Milkweed leaf. There were over thirty of these caterpillars in just a ten by ten feet area this morning. I hope if you’re keeping a habitat for Monarchs, you’re enjoying the same fortune right now!A slow-moving Monarch stopped for a break after making the circuit to deposit eggs on milkweed throughout the garden.Third instar (top), fourth instar (right), and fifth instar (left) Monarch caterpillars quickly consume the leaf of a Common Milkweed plant. Caterpillars emerging from eggs deposited today may not have sufficient late-season food to complete the larval segment of their life cycle. Need more milkweed!After benefitting from the nourishment of the Common Milkweed plant, a fifth instar Monarch caterpillar begins pupation on Big Bluestem grass.Two hours later, the chrysalis is complete.Another chrysalis, this one on flowering Switchgrass just two feet away from the previous one. An adult Monarch will emerge from this pupa to become part of what we hope will be the most populated southbound exodus for the species in over five years.There it is, soon ready to fly away. And all courtesy of the noxious milkweed.A chrysalis can often be found on man-made objects too. This one is on the rim of a flower pot.Ornamental flowers can attract adult Monarch butterflies seeking nectar. I am now more careful to select seeds and plants that have not been treated with neonicotinoid insecticides. There’s growing concern over the impact these compounds may be having on pollinating species of animals. Oh…and I don’t mow, whack, cut, mutilate, or spray herbicides on my milkweed But you probably figured that out already.
SOURCES
Eaton, Eric R., and Kenn Kaufman. 2007. Kaufman Field Guide to Insects of North America. Houghton Mifflin Company. New York.
