Wyoming distribution map
The Lakin grasshopper ranges widely in western North America inhabiting several types of grasslands and desert shrub regions. Its occupancy of a site depends on the presence of a good supply of food plants, especially several members of the goosefoot family (Chenopodiaceae). Native host plants include species of Atriplex and probably species of other genera. In recent times this grasshopper has been aided in its population growth by the invasion of exotic weeds, principally kochia and Russianthistle. Roadsides and fence rows, as well as weedy rangeland, often harbor large numbers of the Lakin grasshopper.
During outbreaks the Lakin grasshopper occasionally becomes a pest of alfalfa, wheat, vegetables, and ornamental flowers. Dense populations inhabiting field margins, fence rows, and roadsides may move into crop land and cause severe damage. When border weeds dried up in 1966, an assemblage of the twostriped, redlegged, and Lakin grasshoppers invaded alfalfa fields in Colorado inflicting considerable damage. Weedy city lots provide favorable breeding areas from which the grasshoppers may move into vegetable and flower gardens.
The Lakin grasshopper is a medium-sized species. Collected from a patch of kochia and Russianthistle on 1 August 1996, 8 miles east of La Junta, Colorado, short-winged males averaged 222 mg live weight and females 331 mg (dry wt 62 mg and 97 mg, respectively).
Examination of crop contents of Lakin grasshoppers collected from a weedy pasture near North Platte, Nebraska showed 94 percent of fragments to be kochia and 1 percent each of lambsquarters, western wheatgrass, and downy brome. In a study of grasshoppers inhabiting desert prairie near Alpine, Texas, crop examinations revealed that Lakin adults were feeding on several species of grasses and forbs, utilizing approximately 40 percent grasses and 60 percent forbs.
Confined in laboratory cages, Lakin grasshoppers fed well on dandelion and young wheat plants. On these host plants, the nymphs survived and developed through the nymphal stage, and the adults matured and reproduced. Surprisingly, in two-choice preference tests, Lakin adults selected greater amounts of dandelion than kochia as their food.
Studies of movement by short-winged species of grasshoppers indicate that distances traveled vary significantly. For example, short-winged adults of Phoetaliotes nebrascensis exhibit daily displacements of 3 to 13 feet and may travel distances of 90 feet or more to reach a better food supply. But a species such as Hypochlora alba, which is mainly short-winged and a faithful occupant of its host plant, Artemisia ludoviciana, exhibits a shorter daily displacement of 0 to 10 feet. A few individuals, both nymphs and adults, remain on the same plant for an entire day. One fifth instar was observed to remain on its host plant for five consecutive days. Regrettably, a review of the latter significant research by Smith and Grodowitz (1987) was omitted in the fact sheet of H. alba (Pfadt 1996). No similar research of movement of the Lakin grasshopper has been done. Its present distribution, however, provides circumstantial evidence that the species has strong powers of dispersal. The common presence of this species in patches of kochia and Russianthistle growing in roadsides, fence rows, city lots, and other isolated areas suggests dispersal into these sites. Probably long-winged individuals colonize new habitats and start an infestation. In subsequent generations, perhaps because of reproductive advantage, short-winged individuals come to outnumber long-winged individuals.
The nymphs are identifiable by their color patterns, shape, and external structures (Fig. 1-5). The head and lobes of the pronotum are noticeably and distinctively striped yellow or tan. In instars I and II the stripes are conspicuous and extend onto the sides of the thorax. In older instars the stripes begin to fade; some may continue to sport stripes while others may lack them except for the crescent.
1. Head in instar I shiny black, yellow or tan line below eye (part of crescent); yellow markings on face; compound eyes with two or three diagonal yellow lines. In instars II to V, head brown or green; crescent yellow or tan, eyes brown with two to three diagonal tan or yellow lines.
2. Pronotal lobes of instars I and II with three curved yellow or tan stripes. Instars III to V may retain the three stripes, but some individuals may have only the crescent stripe.
3. Instar I with medial area of hind femur crossed completely (from top to bottom) by three dark bars. In instars II to V three dark bars located in dorsal half of medial area. Tibia pale gray, tan, green, or blue.
4. Body color is black or fuscous in instar I and brown or green in instars II to V.
No study has been made of egg development in nature. Laboratory research in Arizona has shown that a diapause occurs and that exposure to a cold period is necessary before the eggs complete embryonic development. In nature the hatching period in northern sites appears to extend over approximately five weeks.
The egg pods, deposited by females from La Junta, Colorado into bare soil in the laboratory, were 5/8 to 7/8 inch long, slightly curved, and contained 18 to 22 cream-colored eggs, 3.9 to 4.2 mm long (Fig. 10). In Arizona females oviposit among grass roots and the base of stems. Length of pods is short, 3/8 inch long, and pods contained from 20 to 25 eggs.
In the Texas panhandle, the Lakin grasshopper in 1972 outnumbered other species in a study of weedy rangeland and was present in smaller numbers in 1967 and 1970. No specimens were collected in 1966, 1968, 1969, and 1971. Probably the species was present these years, but in numbers too low to be collected by routine sweeping with an insect net. These data indicate that the density of populations of the Lakin grasshopper fluctuate, but give no hint as to causes.
Patches of kochia and Russianthistle foster and support dense populations of the Lakin grasshopper. In the La Junta site on 4 July 1996, nymphs (III to V instars) numbered 91 per square yard. Four weeks later the density of the population, which consisted now mainly of young adults, decreased to 16 per square yard. Observation showed that the number and volume of kochia and Russianthistle patches had increased. The circumstantial evidence indicated dispersal as well as normal mortality of the population.
In the disturbed site near La Junta, Colorado in July and early August, 1996, Lakin grasshoppers moved vertically on plants in response to environmental conditions. During the night nymphs sat vertically 1 inch below the plant tips, head-up on stems and leaves of kochia. In early July, kochia plants ranged from 8 to 14 inches in height, while Russianthistle plants were just starting to grow. Temperatures during the first week of July were unusually high, reaching 105°F during the early afternoon and decreasing to 70°F by early morning. A month later the majority of nymphs had become adults and both kochia and Russianthistle had grown to 12 to 24 inches in height. During the night the adults rested vertically, head-up on the main and secondary stems 1 to 13 inches below the tips. Temperatures were cooler in early August than in early July with early morning temperatures dipping to 65°F.
One to two hours after sunrise, nymphs and adults climbed and adjusted positions to begin basking in the sun. Oriented vertically and head-up, the majority turned a side perpendicular to the rays of the sun and lowered the associated hindleg. After basking for one to two hours, the grasshoppers backed down 4 to 6 inches. A few crawled with head pointed down, but as soon as they reached the desired lower level, they turned around and faced upward. Many roosted quietly, some stirred and changed position on the host plant, and a few jumped 5 to 6 inches to another host plant.
Feeding began early in the morning from 7 to 8 a.m. when air temperatures ranged from 70° to 75°F. The nymphs fed on the edge of young kochia leaves while adults fed on terminal tissues and leaves of kochia and Russianthistle.
When air temperatures in the afternoon became unusually high, 105°F in early July, the grasshoppers took evasive action. The nymphs rotated on the stems to be in the shade. Further research of the behavior of Lakin grasshoppers is needed to disclose their activities on rangeland.
Bland, R.G. and W.L. Nutting. 1969. A histological and biometrical study of wing development in the grasshopper Melanoplus lakinus. Annals Entomol. Soc. Am. 62: 419-436.
Daniels, N.E. 1973. Grasshopper collections on three land types. Texas Agr. Exp. Stn. MP-1100.
Fry, B., A. Joern, and P.L. Parker. 1978. Grasshopper food web analysis: use of carbon isotope ratios to examine feeding relationships among terrestrial herbivores. Ecology 59: 498-506.
Mulkern, G.B., K.P. Pruess, H. Knutson, A.F. Hagan, J.B. Campbell; and J.D. Lambley. 1969. Food habits and preferences of grassland grasshoppers of the North Central Great Plains. North Dakota Agr. Exp. Stn. Bull. 481.
Nerney, N.J. and A.G. Hamilton. 1966. Effect of insecticide and parasitism on range grasshoppers, San Rafael Valley, Arizona. USDA ARS Entomol. Res. Div. Grain and Forage Res. Branch. Special Report Z-192.
Pfadt, R.E. 1996. Cudweed grasshopper, Hypochlora alba (Dodge). In Field guide to common western grasshoppers, Second Edition. Wyoming Agr. Exp. Stn. Bull. 912.
Smith, G.F. and G. U. Gradowitz. 1987. Displacement of the monophagous grasshopper, Hypochlora alba (Dodge) (Orthoptera: Acrididae), in a patchy environment, Annals Entomol. Soc. Am. 80: 761-764.
Next Species in Subfamily: Melanoplus occidentalis
Previous Species in Subfamily: Melanoplus kennicotti
List of Species Fact Sheets
Field Guide Contents