Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-05T21:29:01.853Z Has data issue: false hasContentIssue false

The Effect of Climate and Weather on the Numbers of the Red Locust, Nomadacris septemfasciata (Serv.), in the Rukwa Valley Outbreak Area

Published online by Cambridge University Press:  10 July 2009

P. Symmons
Affiliation:
International Red Locust Control Service, Abercorn, Northern Rhodesia.

Extract

An examination of the records from 1930 onwards shows that a very high level of Lake Rukwa is correlated with small numbers of the red locust, Nomadacris septemfasciata (Serv.), in the Rukwa Valley outbreak area in Tanganyika. When the lake level is not very high, the size of the adult locust population (taken as that present in the middle of the dry season) is correlated negatively with the total rainfall of the last but one wet season (broadly, November–May), positively with the size of the preceding parental population (taken as that present at the time of oviposition) and possibly also with the rainfall of the preceding October–December, but not significantly with the date of the drop in temperature that is thought to be associated with the start of ovarian development.

Three tentative explanations of the correlation between adult population and rainfall are offered. First, if the water-table is high because of heavy rain in the previous season, the early rains may make the soil unsuitable for successful egg-laying and incubation; second, after a season of heavy rainfall the grass cover may be particularly dense at the end of the following dry season and the consequent reduction of the oviposition sites may make breeding unsuccessful; third, parental mortality may be high during a dry season following heavy rains. These possibilities are being further investigated.

It is suggested that by using a multiple regression equation incorporating the correlations that have been established, the size of the adult locust population can be forecast in time for the scale of hopper control measures to be appropriately modified and economies thereby achieved.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 1959

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Albrecht, F. O. (1956). Limitation des effectifs chez un acridien: influence de la sécheresse du sol sur les oeufs de Nomadacris septemfasciata (Serv.).— Locusta no. 4 pp. 121.Google Scholar
Allan, W. (1931). Locusts in Northern Rhodesia.—Annu. Bull. Dep. Agric. N. Rhod. no. 1 pp. 611.Google Scholar
Bredo, H. J. (1947). Report on the control measures and their organisation against the Red Locust in the outbreak centres Mweru wa Ntipa and Rukwa since 1938.—60 pp., multigraph. (Unpublished.)Google Scholar
Bredo, H. J. (1948). Report on control measures and their organisation against the Red Locust 1947–48.—27 pp., multigraph. (Unpublished.)Google Scholar
Bredo, H. J. (1949). Report on control measures and their organisation against the Red Locust, 1948–49.—36 pp., multigraph. International Red Locust Control Service. (Unpublished.)Google Scholar
Bredo, H. J. (1951). Annual report of the International Red Locust Control Service for 1950–51.—58 pp., multigraph. (Unpublished.)Google Scholar
Bredo, H. J. (1952). Annual report of the International Red Locust Control Service for 1951–52.—19 pp., multigraph. (Unpublished.)Google Scholar
Chaplin, J. H. (1954). On the wet season in Northern Rhodesia.—Weather 9 pp. 272275.CrossRefGoogle Scholar
Faure, J. C. (1935). The life history of the red locust (Nomadacris septemfasciata (Serville)).—Bull. Dep. Agric. S. Afr. no. 144, 32 pp.Google Scholar
Gunn, D. L. (1952). The red locust.—J. R. Soc. Arts 100 pp. 261284.Google Scholar
Gunn, D. L. (1953). Annual report of the Director of International Red Locust Control Service for 1952–53.—70 pp., multigraph. (Unpublished.)Google Scholar
Gunn, D. L. (1954). Report of the Director of International Red Locust Control Service for transitional period 1953.—27 pp., multigraph. (Unpublished.)Google Scholar
Gunn, D. L. (1955 a). Mweru wa Ntipa and the Red Locust.—N. Rhod. J. 2 no. 6 pp. 315.Google Scholar
Gunn, D. L. (1955 b). Annual report of the Director of International Red Locust Control Service for 1954.—57 pp., multigraph. (Unpublished.)Google Scholar
Gunn, D. L. (1956 a). A history of Lake Rukwa and the red locust.—Tanganyika Notes no. 42 pp. 118.Google Scholar
Gunn, D. L. (1956 b). Annual report of the Director of International Red Locust Control Service for 1955.—59 pp., multigraph. (Unpublished.)Google Scholar
Gunn, D. L. (1957). Annual report of the Director of International Red Locust Control Service for 1956.—67 pp., multigraph. (Unpublished.)Google Scholar
Harris, W. V. (1933). The red locust.—Pamphl. Dep. Agric. Tanganyika no. 10, 10 pp.Google Scholar
Lea, A. (1938). Investigations on the red locust, Nomadacris septemfasciata (Serv.), in Portuguese East Africa and Nyasaland in 1935.—Sci. Bull. Dep. Agric. S. Afr. no. 176, 30 pp.Google Scholar
Lea, A. (1958). Recent outbreaks of the brown locust, Locustana pardalina (Walk.), with special reference to the influence of rainfall.—J. ent. Soc. S. Afr. 21 pp. 162213.Google Scholar
Michelmore, A. P. G. (1936). Economic Advisory Council. Committee on Locust Control. Locust investigation in Tanganyika.—Report no. 4, 64 pp., typescript. (Unpublished Report at International Red Locust Control Service.)Google Scholar
Michelmore, A. P. G. (1945). The International Red Locust Control.—Tanganyika Notes no. 20 pp. 17.Google Scholar
Morant, V. (1947). Migrations and breeding of the red locust (Nomadacris septemfasciata Serville) in Africa, 1927–1945.—Anti-Locust Mem. no. 2, 60 pp.Google Scholar
Nicholson, A. J. (1948). Fluctuations of animal populations.—Rep. Aust. Ass. Adv. Sci. 26 pp. 134148.Google Scholar
Rainey, R. C., Waloff, Z. & Burnett, G. F. (1957). The behaviour of the red locust (Nomadacris septemfasciata Serville) in relation to the topography, meteorology and vegetation of the Rukwa Rift Valley, Tanganyika.—Anti-Locust Bull. no. 26, 96 pp.Google Scholar
Robertson, I. A. D. (1954). The numbers of eggs in pods of the red locust, Nomadacris septemfasciata (Serville) (Orth., Acrididae).—Ent. mon. Mag. 90 pp. 254255.Google Scholar
Robertson, I. A. D. (1958). The reproduction of the red locust, Nomadacris septemfasciata (Serv.) (Orthoptera, Acrididae), in an outbreak area.— Bull. ent. Res. 49 pp. 479496.CrossRefGoogle Scholar
Sansom, H. W. (1954). The climate of East Africa based on Thornthwaite's classification.—Mem. E. Afr. Met. Dep. 3 no. 2.Google Scholar
Scheepers, C. C. & Gunn, D. L. (1958). Enumerating populations of adults of the red locust, Nomadacris septemfasciata (Serville), in its outbreak areas in East and Central Africa.—Bull. ent. Res. 49 pp. 273285.CrossRefGoogle Scholar
Smith, R. C. (1954). An analysis of 100 years of grasshopper populations in Kansas (1854 to 1954).—Trans. Kans. Acad. Sci. 57 pp. 397433.CrossRefGoogle Scholar
Symmons, P. & Carnegie, A. J. M. (1959). Some factors affecting breeding and oviposition of the red locust, Nomadacris septemfasciata (Serv.).—Bull. ent. Res. 50 pp. 333353.CrossRefGoogle Scholar
Uvarov, B. P. (1957). The aridity factor in the ecology of locusts and grasshoppers of the Old World.—In Arid zone research: human and animal ecology, pp. 164198. Paris, UNESCO.Google Scholar
Vesey-Fitzgerald, D. (1950). Annual report of the International Red Locust Control Service for 1949–50.—33 pp., multigraph. (Unpublished.)Google Scholar
Vesey-Fitzgerald, L. D. E. F. (1953 a). Report on a visit to the Kafue Flats. —16 pp., typescript. (Unpublished report at International Red Locust Control Service.)Google Scholar
Vesey-Fitzgerald, L. D. E. F. (1953 b). A visit to the Wembere.—21 pp., typescript. (Unpublished report at International Red Locust Control Service.)Google Scholar
Vesey-Fitzgerald, L. D. E. F. (1954 a). Survey of red locust habitats and incidence in the Chambeshi Valley, Northern Rhodesia.—16 pp., typescript. (Unpublished report at International Red Locust Control Service.)Google Scholar
Vesey-Fitzgerald, L. D. E. F. (1954 b). Fire control in red locust outbreak areas and a scheme for its application.—10 pp., typescript. (Unpublished report at International Red Locust Control Service.)Google Scholar
Vesey-Fitzgerald, L. D. E. F. (1955). Survey of red locust habitats and incidence in part of the Luangwa Valley, Northern Rhodesia.—12 pp., typescript. (Unpublished report at International Red Locust Control Service.)Google Scholar