Distribution Patterns of Grasshoppers and Their Kin over the Eurasian Steppes

The main aims of this paper are to reveal general patterns of Orthoptera distribution in the Eurasian steppes, to evaluate long-term trends of changes in distribution of taxa and populations, and to estimate the potential for population changes relative to human activity and global warming trends. The main publications concerning diversity and distribution of these insects over the steppes are analyzed. The fauna of the Eurasian steppes includes more than 440 species of Orthoptera. The general distribution of grasshoppers and their kin in the Eurasian steppes reflects their common associations with different grasslands. The species richness increases from the relatively cold forest-steppes to the semi-deserts with their warm summer. There are some endemic or subendemic taxa, including the tribe Onconotini (Tettigoniidae). The populations’ distribution of Orthoptera is also analyzed. The populations of native Orthoptera extend through all the herbaceous landscapes. Under these conditions, the interrelating of colonies of each species may result in great abundance. The population distribution of three species locusts (Locusta migratoria, Calliptamus italicus, Dociostaurus maroccanus) is also discussed. Some notable changes of their populations’ distribution and dynamics are characterized. The situation with rare Orthoptera is estimated. Retrospective and prospective of the steppe fauna of Orthoptera are discussed.

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MONITORING POPULATION LEVELS OF EIGHT SPECIES OF NOCTUIDS WITH SEX-ATTRACTANT TRAPS IN SOUTHERN ALBERTA, 1978–1983: CONGRUENCY OF YEAR-TO-YEAR FLUCTUATIONS IN INTRASPECIFIC DENSITY SHOWN BY SUBSETS OF MONITORING SITES

The Canadian Entomologist ◽

10.4039/ent1201071-12 ◽

1988 ◽

Vol 120 (12) ◽

pp. 1071-1078 ◽

Cited By ~ 2

Author(s):

J.R. Byers ◽

D.L. Struble ◽

G.B. Schaalje

Keyword(s):

Sex Attractant ◽

Population Estimates ◽

Pest Species ◽

Population Changes ◽

Relative Population ◽

Southern Alberta ◽

Resource Requirements ◽

Long Term Trends

AbstractThe abundance levels of eight species of cutworms and army worms were monitored with sex-attractant traps at 81 locations in a 13 000-km2 area of southern Alberta from 1978 to 1983. Year-to-year change in population levels could be consistently detected by monitoring at a relatively small number of locations. For all species, subsets of selected locations along transects, or random subsets of as few as five locations, showed year-to-year fluctuations in mean catch per trap that were similar in pattern to those of the whole monitored area. The results indicate that long-term surveillance monitoring of pest species of cutworms and armyworms to detect year-to-year population changes, and long-term trends, is feasible in terms of both the resource requirements and reliability of the relative population estimates.

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