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Density Distributions of Hoppers of the Red Locust, Nomadacris septemfasciata (Serv.) (Orth., Acrid.), in Relation to Control by Insecticides

Published online by Cambridge University Press:  10 July 2009

C. C. Scheepers ,
B. J. Eyssell  and
D. L. Gunn
C. C. Scheepers
Affiliation:
International Red Locust Control Service, Abercorn, Northern Rhodesia.
B. J. Eyssell
Affiliation:
International Red Locust Control Service, Abercorn, Northern Rhodesia.
D. L. Gunn
Affiliation:
International Red Locust Control Service, Abercorn, Northern Rhodesia.
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Extract

In continuation of a study of the process of swarm formation in the Red Locust, Nomadacris septemfasciata (Serv.), to enable rational plans for control measures to be made, the population distribution of about 44½ million hoppers of the Red Locust was investigated in an observation area of 1,052 acres in the Iku outbreak area of the Rukwa Valley, Tanganyika Territory, from 18th January to 24th February 1957. to see if the hoppers showed a tendency to concentrate, which would have the effect of producing, immediately after the last moult, adult swarms from hoppers that were originally more scattered. From 25th January onwards, the estimated population remained constant in numbers. Densities over 50 per sq. yd. were unusual and, taking any continuous infestation over one per sq. yd. as a band, the mean density of hoppers in bands was 15 per sq. yd. There was a tendency for such bands to become larger by fusion and for the area quite free from locusts to increase slightly but the number of dispersed locusts increased. There would therefore have been no advantage in withholding insecticide control in the hope of attacking denser and more economical targets. Nevertheless, such populations have to be controlled.

In the Red Locust, under the conditions described, it seems probable that the behaviour of the young adults is most important in the formation of dense swarms, while in certain other species but not in the Red Locust, concentrated egg-laying and the behaviour of the hoppers are also important.

Investigations are required on more economical enumeration of patchy gregarious distributions.

Type
Research Paper
Information
Bulletin of Entomological Research , Volume 49 , Issue 3 , September 1958 , pp. 467 - 478
Copyright
Copyright © Cambridge University Press 1958

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References

Backlund, H. O. (1956 a). Red locusts and vegetation.—Oikos, 6 (1955), pp. 124–148.CrossRefGoogle Scholar
Backlund, H. O. (1956 b). Aspects and successions of some grassland vegetation in the Bukwa Valley, a permanent breeding area of the Red Locust.—Oikos, suppl. 2, 132 pp.Google Scholar
Chapman, R. F. (in press). Field observations on the nymphs of the Red Locust, Nomadacris septemfasciata (Serville).—Anti-Locust Bull., no. 33.Google Scholar
Ellis, P. E. (1951). The marching behaviour of hoppers of the African Migratory Locust (Locusta inigrcrtoria migratorioides R. & F.) in the laboratory.—Anti-Locust Bull., no. 7, 46 pp.Google Scholar
Ellis, P. E. (1953a). The gregarious behaviour of marching Locusta migratoria migratorioides (R. & F.) hoppers.—J. exp. Biol., 30, pp. 214–234.CrossRefGoogle Scholar
Ellis, P. E. (1953 b). Social aggregation and gregarious behaviour in hoppers of Locusta migratoria migratorioides (R. & F.).—Behaviour, 5, pp. 225–260.CrossRefGoogle Scholar
Ellis, P. E. (1956). Differences in social aggregation in two species of locust.—Nature, Lond., 178, p. 1007.CrossRefGoogle Scholar
Ellis, P. E. & Ashall, C. (1957). Field studies on diurnal behaviour, move ment and aggregation in the Desert Locust (Schistocerca gregaria Forskål).—Anti-Locust Bull., no. 25, 94 pp.Google Scholar
Gunn, D. L. (1952a). Control of Red Locusts by insecticides.—J. Sci. Fd Agric., 3, pp. 289–296.CrossRefGoogle Scholar
Gunn, D. L. (1952 b). The Red Locust.—J. R. Soc. Arts, 100, pp. 261–284.Google Scholar
Gunn, D. L. (1957). The story of the International Red Locust Control Service.—Rhod. agric. J., 54, pp. 8–24.Google Scholar
Gunn, D. L., Lloyd, J. H. & Davey, P. M. (1954). The choice of insecticides for destroying Red Locusts in their outbreak areas.—J. ent. Soc. S. Afr., 17, pp. 246–251.Google Scholar
kennedy, J. S. (1939). The behaviour of the Desert Locust (Schistocerca grega (Forsk.)) (Orthopt.) in an outbreak centre.—Trans. R. ent. Soc. Lond., 89, pp. 385–542.CrossRefGoogle Scholar
Plotnikov, V. I. (1931). The increase in the area occupied by bands of Docio staurus maroccanus Thunb., and the rate of its control. [In Russian.]—[Byull.]Sr.-Az. Inst. Zashch. Rast., no. 25, 11 pp. (Rev. appi. Ent. (A) 19, p. 410.)Google Scholar
Scheepers, C. C. & Gunn, D. L. (1958). Enumerating populations of adults of the Red Locust, Nomadacris septemfasciata. (Servile), in its outbreak areas in East and Central Africa.—Bull. ent. Res., 49, pp. 273–285.CrossRefGoogle Scholar
Smit, C. J. B. (1939). Field observations on the Brown Locust in an outbreak centre.—Sci. Bull. Dep. Agric. S. Afr., no. 190, 143 pp.Google Scholar
Vesey-Fitzgerald, D. F. (1955). The vegetation of the outbreak areas of the Red Locust (Nomadacris septemfasciata Serv.) in Tanganyika and Northern Rhodesia.—Anti-Locust Bull., no. 20, 31 pp.Google Scholar