The small, wingless grasshoppers you may notice in the spring and early summer are not a different species of grasshopper than the winged varieties noticeable in late summer and fall. The wingless grasshoppers are actually young grasshoppers in the nymph life stage, waiting for their wings to grow and become functional. Grasshoppers actually have incomplete metamorphosis or incomplete life cycles because they only pass through three stages of life: eggs, nymphs and adulthood.
Female grasshoppers begin laying eggs in late July and continue throughout the fall by depositing eggs into the soil. Females lay eggs in egg-shaped pods that include between 20 and 120 individual eggs each. A single female grasshopper will lay between 8 to 25 different egg pods. Eggs may overwinter underground before hatching in the spring, though some grasshopper species will hatch in the fall and overwinter as nymphs.
Nymphs closely resemble adult grasshoppers, except that they do not have fully developed or functional wings. The nymph life stage of grasshoppers lasts approximately 40 to 60 days and includes five to six nymphal stages, called instars. Between each instar, nymphs moult to lose their outer skins. During each instar, grasshoppers' wings develop and their bodies increase in size.
During the first through third instars, the wings on nymph grasshoppers will appear on the nymph's thorax, as saddle-like, non-protruding growths. Once the nymph moults and passes into the fourth and fifth instar, the wingpads produce protruding growth that points backwards over the first segment of the nymph's abdomen. During the fifth instar, the wings increase in size, extending over the second segment of the nymph's abdomen. A final moulting passes the nymph into the sixth instar, adulthood, during which wings are full-grown and the insects begin to reproduce.
As adults, grasshoppers have fully functional wings and can now fly over short or long distances, depending on species, in addition to jumping. Once they reach adulthood, grasshoppers can mate and lay eggs to restart the life cycle. Adult male grasshoppers will call females with a chirping noise produced from the stridulating organ at the wing base. The male then mounts females, who respond to his mating call and connects his abdomen with hers to fertilise the eggs she will lay within the soil.
- North Dakota State University; Grasshopper Biology and Management; Phillip A. Glogoza; February 1997
- University of Kentucky Entomology; Grasshoppers & Katydids; Blake Newton; May 2004
- University of Kentucky Entomology; Three Common Kentucky Grasshoppers and Their Natural Enemies; D. Shanklin, et al.