May/June 2008For Wildlife Watchers: Grasshopper by Rob Simbeck, photography by Michael Foster
South Carolina's state parks celebrate 75 Years of providing access to recreation, natural beauty and cultural enrichment in the Palmetto State.
Her name was Juliette, and she was a lovely creature - lean and graceful, with sleek curves and an elegant bearing. I can still picture her, perched sunnily on my index finger, eating like there was no tomorrow.
Juliette was a yellow-billed cuckoo. Debby, my better half, had seen her fly into the side of a car one summer morning and stopped to pick her up and bring her home. As her hotelier, maitre d' and waiter, I can tell you that her dining predilection, both for appetizers and entrees, ran to grasshoppers. It fell to me to deliver them, and while they are quick and elusive, Juliette was charmingly insatiable and I was willing to learn. I became quite accomplished at stealth through the high weeds behind the house, coming in low and from the rear with a quick right-handed grab. Even so, both she and I welcomed my graduation to the use of a butterfly net.
Grasshoppers' elusiveness has been hard-won. Plenty of creatures recognize them as a great source of protein, with birds, lizards, rodents and other mammals, and spiders all on the list. Their predator-avoidance techniques are numerous. First and foremost is camouflage - both their color and build help them blend in with their surroundings, and when they are still, facing the sun to minimize shadows, they can be nearly impossible to see. Then there is that lightning-quick jump, driven by large hind legs and supplemented in many species by flight, powered by the larger of two pairs of wings. I can tell you from experience that knowing where they land isn't all that much help.
"When they hit the ground," says Bob Bellinger of Clemson University's Department of Entomology, Soils and Plant Sciences, "they will quickly run off to one side. They can be just four, five or six inches away, but you're not going to see them."
When grasshoppers are not falling prey to larger creatures, they can be menaced by smaller ones. They are parasitized by worms found in the soil and by certain flies, and there are tiny wasps that latch onto them in flight and parasitize the eggs subsequently laid by females. Some fungi also spur behavioral changes in grasshoppers, causing them to climb up on plants before they die, giving the fungi's spores a higher perch from which to disperse. Bellinger tells of seeing "thousands of dead grasshoppers clinging to the upper stalks of plants along the highway."
Grasshopper - Suborder Caelifera
Description: Generally brown to green in color, although some species have yellow, black or red markings. Up to 3 inches long in South Carolina, 4 inches elsewhere.
Range and Habitat: Throughout continental U.S. Throughout South Carolina. Various species adapted to most soils and climates.
Reproduction: After mating, females lay pods containing fertilized eggs in soil. Most overwinter; some hatch late in fall. Incomplete metamorphosis, several molts.
Viewing Tips: Grasshoppers are relatively easy to spot in any grassy field or along dirt roads. Look for them climbing through and onto grass stalks, jumping as you disturb their habitat. Late summer and fall are best.
Grasshoppers are a menace mainly to plant life. Some climb grass and weed stalks, feeding on leaves, seeds or buds; some stay on the ground to feed on animal and vegetable matter strewn about; and some actually cut grass or plant stalks as though they were harvesting timber for dining purposes. Among them, they'll eat a little of everything plant-related, testing for culinary acceptability with a touch of sensitive antennae tips that serve as tasters.
The female is equipped with another testing kit, this one useful in the reproductive process. Once she is ready to lay eggs, her ovipositor takes soil readings, looking for just the right conditions. Different species have different preferences, and the soil may be sandy, rocky or loamy. The number of eggs, laid in pods, varies with the size of the species, from about ten in the smallest to about one hundred in the largest. The number of pods laid per year varies with temperature, moisture and food quality, among other factors. The female digs with two pairs of triangular valves at the end of her abdomen and secretes a foamy substance around the eggs that hardens and protects them from weather, parasites and predators. Climate dictates what happens next, as some eggs hatch relatively quickly while others develop only until the temperature drops sufficiently, when they become dormant until spring.
The eggs look like little rice grains, and the first nymphs to hatch tunnel to the surface, with the rest from that pod following, generally within a few minutes. These are insects that undergo incomplete metamorphosis, growing as nymphs that look like adults without wings or reproductive organs. They molt as many as six to eight times, depending on geography, species and sex - females, which tend to be larger, go through an extra molt - by swallowing air to build up pressure that splits the old cuticle and finally becoming adults with functional wings. Internally, they do not have a complex blood circulatory system, nor do they have lungs. A green blood-like fluid circulates through relatively open spaces in the grasshopper's body, carrying nutrients and picking up waste, and air-filled tubes that open at the surfaces of the abdomen and thorax allow for the exchange of oxygen and carbon dioxide.
Grasshoppers are part of a large group of insects that includes crickets, katydids and locusts. The family that includes grasshoppers, Acrididae, contains more than 10,000 species, with some individuals reaching 4 inches long.
South Carolina has from thirty to forty species, says Bellinger, with the most noticeable, if not the most common, being the banded-wing grasshoppers. They are large and produce sound when they fly, calling our attention to them more often - and, for that matter, throwing an instant's confusion at predators.
The protein that draws so many creatures to eat grasshoppers draws people, too, particularly in Asia and Africa, where they're often fried. Sound environmental and nutritional reasons exist for eating them, although the aesthetics may take some getting used to.
That wasn't a problem, of course, for Juliette, who remained the picture of health on a grasshopper diet. Me, I was never tempted.