Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-26T17:03:07.881Z Has data issue: false hasContentIssue false

Simultaneous control of three species of Glossina by the selective application of insecticide

Published online by Cambridge University Press:  10 July 2009

K. J. R. Maclennan
Affiliation:
Tsetse and Trypanosomiasis Unit, Ministry of Animal and Forest Resources, Northern Nigeria.
P. J. Aitchison
Affiliation:
Tsetse and Trypanosomiasis Unit, Ministry of Animal and Forest Resources, Northern Nigeria.

Extract

An account is given of the simultaneous control of three species of tsetse fly by the selective application of insecticide to vegetation within an area of 16 sq. miles along a seasonal watercourse in Northern Nigeria constituting a permanent habitat of Glossina palpalis (R.-D.) and G. tachinoides Westw. and a hot-season concentration area of G. morsitans Westw. subsp. submorsitans Newst. The ecological zones concerned centred on small lakes fringed, in succession outwards, by open swamp, swamp woodland, swamp forest, riparian forest and riparian woodland, the whole being bounded by savannah woodland populated by G. morsitans in the wet season. All except the forest elements were subject to seasonal fires.

Against G. morsitans, insecticide was applied to the principal resting sites of flies in their hot-season concentration habitats, namely, the basal 5 ft. of shaded tree trunks over 9 in. in diameter, or 5 in. where stands were dense, in, chiefly, riparian woodland and forest. Against the other species it was applied to a height of 2½ ft. on stems, trunks and exposed roots in riparian forest and the margins of swamp forest, which were favoured as pupation sites and in which it was therefore believed that adults might rest.

A wettable-powder suspension containing 3¾ per cent. DDT was applied by pneumatic knapsack sprayer in quantities short of run-off. Temporary reduction of the strength to 2½ per cent, had no detectable effect on control.

Regular fly patrols showed an initial reduction in apparent density of G. morsitans by four-fifths, but spot checks detected a residual population that persisted up to two months in small areas. These were resprayed so as to include trunks of 5 in. diameter and branches over 3 in. in diameter at heights of 6–12 ft. The apparent density of the other species declined after treatment by over nine-tenths, in both treated and untreated zones, but following catches of a few teneral adults, indicating persistent or recurrent populations in limited areas, these were resprayed using an emulsion containing 3¾ per cent, dieldrin.

Treatment began in January 1961 and to date (April 1963) no fly has been detected since April 1961, despite repeated re-surveys. The approximate cost of labour, equipment and insecticide was £3,000; an attempt at reclamation in 1926–29 by sheer-felling over seven sq. miles, which achieved only temporary success, had cost £3,000, with recurrent annual re-slashing costs of £250, equivalent to £12,000 and £1,500, respectively, at present-day costs for labour.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 1963

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

Blasdale, P. [1961]. The development of a practical means of eradicating Glossina morsitans submorsitans Newst. and G. tachinoides West, in the Sudan savannah zone of Northern Nigeria.—8th Mtg int. sci. Comm. Tryp. Res., Jos 1960 pp. 295302.Google Scholar
Davies, H. & Blasdale, P. (1960). The eradication of Glossina morsitans submorsitans Newst. and Glossina tachinoides Westw. in part of a river flood plain in Northern Nigeria by chemical means. Part III.—Bull, ent. Res. 51 pp. 265270.CrossRefGoogle Scholar
Davies, J. B. (1958). An attempt to eradicate Glossina palpalis (R.-D.) and G. tachinoides Westw. from riverine vegetation in Benue Province, Northern Nigeria, by spraying with DDT.—Bull. ent. Res. 49 pp. 427436.CrossRefGoogle Scholar
Keay, R. W. J. (1953). An outline of Nigerian vegetation.—2nd edn., 55 pp. Lagos, Govt. Printer.Google Scholar
Kirkby, W. W. & Blasdale, P. (1960). The eradication of Glossina morsitans submorsitans Newst. and Glossina tachinoides Westw. in part of a river flood plain in Northern Nigeria by chemical means. Part II.—Bull, ent. Res. 51 pp. 253264.CrossRefGoogle Scholar
Lloyd, Ll., Lester, H. M. O., Taylor, A. W. & Thornwill, A. S. (1933). Experiments in the control of tsetse fly. Part II.—Bull. ent. Res. 24 pp. 233251.CrossRefGoogle Scholar
Maclennan, K. J. R. & Kirkby, W. W. (1958). The eradication of Glossina morsitans submorsitans Newst. in part of a river flood plain in Northern Nigeria by chemical means.—Bull. ent. Res. 49 pp. 123131.CrossRefGoogle Scholar
Nash, T. A. M. (1937). Climate, the vital factor in the ecology of Glossina.— Bull. ent. Res. 28 pp. 75127.CrossRefGoogle Scholar