The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Sunday, July 02, 2006

Grasshoppers Are Fascinating Insects
by Ro Wauer

With the arrival of summer, with its hot and dry days (especially this year), grasshopper populations are on the increase. Although most species begin to appear in mid-spring, others wait to put in their appearance during summer. Some years various species can occur in such large numbers that they can literally destroy their food supply. Farmers can loose much of their crops, including sorghum, corn, soybeans, and cotton. And those of us with gardens, including those designed to attract butterflies, can suffer as well.

Texas has more than 80 species of grasshoppers, and all of those have been included within a recent book, titled "Field Guide to Grasshoppers, Katydids, and Crickets of the United States," by John Capinera, Ralph Scott and Thomas Walker. Published by Comstock Publishing Associates, a division of Cornell University, it includes species descriptions, along with excellent paintings of most species, and up to date range maps. And I found the key to species identification easy to use and most helpful. The introduction section is also well done. It includes good information on features, life history, habitats and food, ecological significance, and biogeography.

Here is a brief listing of some of our local species. The huge, reddish, eastern lubber grasshopper is one of the best known of all grasshoppers. The skinny toothpick-like grasshopper is Sumichrast's toothpick grasshopper. The common mid-sized, green-bodied species is graceful range grasshopper. The large-headed, green species is elegant grasshopper. The mid-sized, brown mottled species is the southwestern dusky grasshopper. Other local species include the three-banded range grasshopper, orange-winged grasshopper, ridgeback sand grasshopper, meadow purple-striped grasshopper, and red-legged grasshopper. Several of these are readily identified by their name.

Grasshoppers, katydids, and crickets are closely related, all lumped by entomologists in the insect order Orthoptera. A major reason for this classification is their life history. Unlike some other insect orders, such as Lepidoptera (butterflies and moths) that undergo a complete metamorphosis, Orthopteras undergo a simple (or gradual) metamorphosis. Their principal life forms include only the egg, nymph, and adult. The nymph and adult forms progress with minimal change in appearance. Grasshopper females deposit eggs (4 to 100) in groups, usually in the soil in a cluster held together by a frothy secretion. As it dries it forms a rigid covering that protects the eggs, collectively known as an egg pod.

Upon hatching, usually in spring, the young grasshopper, called a nymph prior to reaching adult size, simply digs its way through the soil and molts. It is then a walking, hopping, and eating immature grasshopper. Wings develop gradually as the nymph progresses through five or six molts (instars) to reach breeding stage. Their old body covering is shed with each molt.

Typical grasshopper females lay eggs in late summer and fall, the eggs hatch in spring, nymphs develop during the summer, and the adults mate and produce eggs in the summer and fall. The nymphs and adults of some southern species can be found nearly year-round. But most species produce a single generation annually, although the life cycle of more northern or high altitude species take more than one year from egg to adult.

Grasshoppers generally are considered the most abundant aboveground of all insects. And they probably are one of the most important for a number of reasons. Their feeding habitats, especially during eruptive years, can have very significant negative effects upon food crops, and they can actually decimate some habitats. On the other hand, grasshoppers are one of the most important foods for an amazing variety of other animals, from mammals to birds, to reptiles and amphibians, and even other larger insects. Since grasshoppers are 50 to 75 percent crude protein, they even help maintain the survival of millions of human beings in much of the world.