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Some Ecological Factors Affecting the Grasshopper Populations of Western Canada

Published online by Cambridge University Press:  31 May 2012

Roy L. Edwards
Affiliation:
Department of Biology, University of Saskatchewan, Saskatoon, Saskatchewan

Abstract

The underlying causes of grasshopper outbreaks in Western Canada are of interest both as an academic problem in insect population dynamics and as a practical problem in modern agriculture. Grasshopper populations reach their annual low point in early July when they are in the adult stage and increase sharply in the fall at the time of oviposition. Any factor that influences the grasshoppers during this period may have a marked effect on the outbreak of the following year. The relationship between grasshopper population numbers and proceeding fall temperatures may either control grasshopper populations directly by affecting their physiology or indirectly by affecting their parasites, predators, and diseases. Studies at the University of Saskatchewan aimed at solving this problem include investigation of the microclimate to which grasshoppers are subjected under field conditions, a survey of their feeding habits as shown by crop analyses, and a study of their oviposition behaviour. On the basis of available information an attempt is being made to predict future outbreaks at least 6 months in advance.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1964

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References

Baird, R. B. 1958. Field experiments with Pseudomonas aeruginosa (Schroeter) Migula to control grasshoppers. Canad. Ent. 90: 8991.Google Scholar
Brooks, A. R.Acridoidea of Southern Alberta, Saskatchewan and Manitoba (Orthoptera). Canad. Ent. 90 (Suppl. 9), 92 pp.Google Scholar
Brusven, M. A., and Mulkern, G. B.. 1960. The use of epidermal characteristics for the identification of plants recovered in fragmentary conditions from the crops of grasshoppers. N. Dak. Agric. Exp. Sta. Res. Rep. 3: 111.Google Scholar
Bucher, G. E. 1959. Bacteria of grasshoppers of Western Canada: III Frequency of occurrence, pathogenicity. J. Ins. Path. 1: 391405.Google Scholar
Coupland, R. T. 1961. A reconsideration of grassland classification in the Great Plains of North America. J. Ecol. 49: 135167.Google Scholar
Criddle, N. 1917. Popular and practical entomology. Precipitation in relation to insect prevalence and distribution. Canad. Ent. 49: 7780.CrossRefGoogle Scholar
Edwards, R. L. 1960. Relationship between grasshopper abundance and weather conditions in Saskatchewan, 1930-1958. Canad. Ent. 92: 619624.Google Scholar
Edwards, R. L. 1962. A critical appraisal of grasshopper forecast maps in Saskatchewan, 1936-1958. J. econ. Ent. 55: 288292.CrossRefGoogle Scholar
Haskell, P. T. 1959. Knowing one's enemy is the clue? New Scientist 6: 11081109.Google Scholar
Hope, E. C. 1938. Weather and crop history in Western Canada. Canad. Soc. techn. Agric. Rev. Ottawa 347358.Google Scholar
Isely, F. B., and Alexander, G.. 1949. Analysis of insect food habits by crop examination. Science 109: 115116.Google Scholar
MacCarthy, H. R. 1956. A ten-year study of the climatology of Melanoplus mexicanus mexicanus (Sauss.) (Orthoptera: Acrididae) in Saskatchewan. Canad. J. agric. Sci. 36: 445462.Google Scholar
O'Meara, W. 1925. The savage county. Houghton Mifflin, Boston.Google Scholar
Parker, J. R. 1933. Factors largely responsible for years of grasshopper abundance. Proc. World's Grain Exhibition and Conf., Canada 2: 472473.Google Scholar
Pickford, R. 1958. Observations on the reproductive potential of Melanoplus bilituratus (Wlk) (Orthoptera: Acrididae) reared on different food plants in the laboratory. Canad. Ent. 90: 483485.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
Putnam, L. G., and Shklov, N.. 1956. Observations on the distribution of grasshopper eggpods in Western Canadian Stubble fields. Canad. Ent. 88: 110117.Google Scholar
Smith, R. W. 1958. Parasites of nymphal and adult grasshoppers (Orthoptera: Acrididae) in Western Canada. Canad. J. Zool. 36: 217262.Google Scholar
Spencer, G. J. 1940. The effect of hailstorms on grasshoppers. Canad. Ent. 72: 233234.Google Scholar
Spencer, G. J. 1958. The natural control complex affecting grasshoppers in the dry belt of British Columbia. Proc. 10th int. Congr. Ent., Montreal 5: 497502.Google Scholar