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Surveys of Adult Grasshoppers in Saskatchewan in Relation to Seasonal Development1

Published online by Cambridge University Press:  31 May 2012

P. W. Riegert
Affiliation:
Entomology Section, Canada Agriculture Research Station, Saskatoon, Saskatchewan
R. Pickford
Affiliation:
Entomology Section, Canada Agriculture Research Station, Saskatoon, Saskatchewan

Abstract

In the past twenty years in Saskatchewan the rate of nymphal development of three species of grasshoppers has varied considerably from year to year and region to region. Camnula pellucida appeared as early as, or earlier than, the other two species. The average date of attainment of the adult stage was July 21 compared to August 4th for Melanoplus bilituratus and M. bivittatus. Adult surveys in Saskatchewan have generally coincided with the time when the dominant species of grasshoppers, in any region, have attained full morphological and sexual maturity and have had an opportunity to disperse and stabilize density. Duration of the surveys, in any one of seven regions, in the years 1958-1961, varied from 4-31 days and averaged 19 days per year. The total period of survey for the province varied from 25-42 days and averaged 30 days per year.

Variations in seasonal histories of the several grasshopper species demand an elastic schedule for surveys. The concept of maintaining a standard and rigid “best time” for surveys is untenable in the light of the present investigations.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1963

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References

Barnes, O. L. 1944. Time schedules for grasshopper surveys in Arizona. Jour. Econ. Ent. 37: 789795.CrossRefGoogle Scholar
Edwards, R. L. 1962. The importance of timing in adult grasshopper surveys. Jour. Econ. Ent. 55: 263264.CrossRefGoogle Scholar
Moore, H. W. 1948. Variations in fall embryological development in three grasshopper species. Canad. Ent. 80: 8388.CrossRefGoogle Scholar
Pickford, R. 1960. Survival, fecundity and population growth of Melanoplus bilituratus (Wlk.) (Orthoptera: Acrididae) in relation to date of hatching. Canad. Ent. 92: 110.CrossRefGoogle Scholar