Hostname: page-component-8448b6f56d-xtgtn Total loading time: 0 Render date: 2024-04-24T03:54:55.144Z Has data issue: false hasContentIssue false
  • English
  • Français

Seasonal changes in distribution of the African armyworm, Spodoptera exempta (Wlk.) (Lep., Noctuidae), with special reference to eastern Africa

Published online by Cambridge University Press:  10 July 2009

E. S. Brown ,
Elizabeth Betts  and
R. C. Rainey
Get access Rights & Permissions [Opens in a new window]

Extract

Emigration of moths of the Noctuid Spodoptera exempta (Wlk.) from their developmental sites occurred within a few hours of emergence, and captive moths have lived in semi-outdoor conditions for several weeks. Flight has been recorded at all times of night in the Kenya highlands, and has shown a very marked association, seasonally, nightly and even hourly, with rain; it has been observed at temperatures down to 13°C, and inferred at temperatures several degrees lower, so that over the greater part of eastern Africa flight activity is very unlikely to be restricted by low temperatures.

The breeding season of S. exempta differs markedly and consistently in different parts of eastern Africa; outbreaks of larvae recorded over the past forty years in Kenya, Tanzania and Uganda have been confined to November-July (very largely to December-May), alternating with those recorded over the past twenty years in Ethiopia, which have been confined to March-December (very largely April to August). The progressive establishment of a network of fifty light-traps in these countries since late 1962 has repeatedly recorded the arrival of invading moths before the first infestations of larvae, and has also provided evidence of a strikingly complete seasonal evacuation of much of the region; all traps in Kenya and most of those in Tanzania have revealed a period of several months in every year without a single moth of S. exempta.

Seasonal successions of moth catches and outbreaks of larvae have provided repeated evidence of a progressive northward movement of populations of S. exempta, developing in March in Tanzania and Kenya, and extending across Ethiopia, in some years as far as northern Eritrea by June. The extent of these inferred displacements is consistent with the evidence so far available on behaviour and other factors affecting range of flight, which has been examined in as much detail as the limited data permit.

Evidence of a return migration southwards to Kenya and Tanzania is relatively scanty. There are some indications of a north to south sequence of moth catches and outbreaks; the heaviest infestations in Kenya and Tanzania during the four-year period of detailed study were preceded by the largest catches so far recorded at the relevant time of year in Ethiopia; and in several years the first moths arriving in Kenya and Tanzania, in November-December, have appeared with the onset of the north-east monsoon, representing the southward movement of the intertropical convergence zone. Conversely, appearances of moths towards the northern limits of their inferred seasonal migration, in Ethiopia and around the Gulf of Aden in June, have shown an analogous association with the establishment of the south-west monsoon, i.e., with the northward movement of the intertropical convergence zone. Brief reference is made to evidence of seasonal migration in other parts of Africa; possibly in some years the eastern African populations may be supplemented by migrants from the south.

Two recorded moth ‘ swarms ’ have been associated with weather systems characterised by particularly vigorous wind-convergence. It is suggested that wind-convergence may have contributed to the density of the ‘ swarms ’ and of the subsequent infestations of larvae.

The overall effect of the seasonal changes in distribution which have been demonstrated is to bring the population into areas experiencing seasonal rains. Such a pattern of seasonal migration is likely to be of particular survival value for grass-eating insects, and such concentration of the insects as may be attributable to the associated wind-convergence may be significant in relation to the status of such insects as pests of cereal crops.

Records in the literature of long-range geographical displacements of some other Lepidoptera have been found to be associated in a similar manner with analogous systems of wind and weather in other parts of the world.

Type
Research Paper
Information
Bulletin of Entomological Research , Volume 58 , Issue 4 , May 1969 , pp. 661 - 728
Copyright
Copyright © Cambridge University Press 1969

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

Abu Sharr, Werqu Merkasha, Dalton, J. H. & Eichberger, W. G. (1967). Report of the survey mission on the agricultural development of Setit-Humera area.—71 pp., multigraph. Addis Ababa, Inst. Agric. Res.Google Scholar
Anon. (1954). Reviews of the work in economic entomology in the Commonwealth 1948–54.—Rep. 6th Commonw. ent. Conf. 1954 pp. 161–344.Google Scholar
Arnol’di, K. V. (1955). Hibernation of Eurygaster intergriceps Put. in the mountains of Kuban in the light of investigations in 1949–1953. [In Russian.] In Fedotov, D. M. Ed. The noxious Pentatomid, Eurygaster integriceps Put. Vol. 3, pp. 171–237.Google Scholar
Brown, E. S. (1962). The African armyworm Spodoptera exempta (Walker) (Lepidoptera, Noctuidae): a review of the literature.—57 pp., multigraph. London, Commonw. Inst. Ent.Google Scholar
Brown, E. S. (1964). Army worm research.—Rec. Res. E. Afr. agric. For. Res. Org. 1963 pp. 63–74.Google Scholar
Brown, E. S. (1965a). Notes on the migration and direction of flight of Eurygaster and Aelia species (Hemiptera, Pentatomoidea) and their possible bearing on invasions of cereal crops.—J. Anim. Ecol. 34 pp. 93–107.CrossRefGoogle Scholar
Brown, E. S. (1965b). Army worm research.—Rec. Res. E. Afr. agric. For. Res. Org. 1964. pp. 24–36.Google Scholar
Brown, E. S. (1966). Army worm.—Rec. Res. E. Afr. agric. For. Res. Org. 1965 pp. 160–171.Google Scholar
Brown, E. S. (1967). Army worm.—Rec. Res. E. Afr. agric. For. Res. Org. 1966 pp. 132–150.Google Scholar
Brown, E. S. (1968). Army worm.—Rec. Res. E. Afr. agric. For. Res. Org. 1967 pp. 101–112.Google Scholar
Brown, E. S., & Swaine, G. (1966). New evidence on the migration of moths of the African armyworm, Spododptera exempta (Wlk.) (Lepidoptera, Noctuidae).—Bull. ent. Res. 56 pp. 671–684.CrossRefGoogle Scholar
Caswell, G. H. (1962). Agricultural entomology in the tropics.—152 pp. London, Edward Arnold.Google Scholar
Clackson, J. R. (1947). Notes on forecasting in East Africa.—6 pp. Nairobi, Met. Serv. Pr.Google Scholar
CochemÉ, J. A. (1966). Wind opportunities for locust transport and concentration in India and West Pakistan, 06 1961.—F.A.O. Rep. no. UNSF/DL/RFS/6, 59 pp.Google Scholar
Commonwealth Institute Of Entomology (1955). Laphygma exempta (Wlk.).—Distrib. Maps Insects Pests no. 53.Google Scholar
Darling, H. S. (1949). Cotton growing at Zeidab, northern Sudan, and the control of Laphygma exigua.—Emp. Cott. Grow. Rev. 26 pp. 271–277.Google Scholar
Davidson, A. (1966). Observations on the control of insecticide-resistant Laphygma frugiperda on irrigated maize in Pernambuco, Brazil.—Pl. Prot. Bull. F. A. O. 14 pp. 77–79.Google Scholar
Davidson, A. (1967). The control of cotton pests in the northeast. Report to the Government of Brazil.—F.A.O. Rep. no. TA.2284, 36 pp.Google Scholar
Dowdeswell, W. H., Fisher, R. A. & Ford, E. B. (1949). The quantitative study of populations in the Lepidoptera: 2. Maniola jurtina L.—Heredity, Lond. 3 pp. 67–84.CrossRefGoogle Scholar
East African Meteorological Department (1961). Frequencies of surface wind speeds and directions; part I, Kenya (including Seychelles Islands).—Nairobi, E. Afr. Common Serv. Org.Google Scholar
East African Meteorological Department (1964). Daily rainfall in Tanzania, December 1964.—Nairobi, E. Afr. Common Serv. Org.Google Scholar
East African Meteorological Department (1965a). Daily rainfall in Kenya, November 1965.—Nairobi, E. Afr. Common Serv. Org.Google Scholar
East African Meteorological Department (1965b). Daily rainfall in Tanzania, November 1965.—Nairobi, E. Afr. Common Serv. Org.Google Scholar
East African Meteorological Department [?1947]. Instructions and tables for sunrise and sunset computations. O.M. no. 20.Google Scholar
Ethiopian Meteorological Department (1966).—Monthly climatic summary, 06 1966.Google Scholar
F.A.O. (1958). Report of 8th Session of FAO Technical Advisory Committee on Desert Locust Control.—33 pp.Google Scholar
Faure, J. C. (1943). Phase variation in the armyworm Laphygma exempta (Walk.).—Sci. Bull. Dep. Agric. S. Afr. no. 234 (2), 17 pp.Google Scholar
Flohn, H. (1960). Equatorial westerlies over Africa, Their extension and significance. In Tropical meteorology in Africa.—Nairobi, Proc. WMO and Munitalp Symposium pp. 56–137.Google Scholar
Fonseca Ferrao, A. P. S. & Santos, F. H. (1965). Estudos preliminaries sobre Laphygma exempta Wlk.—4a Jornadas silvo-agron. 2. pp. 173–197.Google Scholar
Glick, P. A. (1939). The distribution of insects, spiders, and mites in the air.—Tech. Bull. U. S. Dep. Agric. no. 673, 150 pp.Google Scholar
Glover, J., Robinson, P. & Henderson, J. P. (1954). Provisional maps of the reliability of annual rainfall in East Africa.—Q. Jl R. met. Soc. 80 pp. 602–609.CrossRefGoogle Scholar
Gunn, D. L. (1960). Nomad encompassed: the development of preventive control of the red locust, Nomadacris septemfasciate Serville, by the International Red Locust Control Service.—J. ent. Soc. sth. Afr. 23 pp. 65–125.Google Scholar
Harris, W. V. (1944). The armyworm.—E. Afr. agric. J. 10 pp. 2–6.Google Scholar
Hattingh, C. C. (1941). The biology and ecology of the armyworm (Laphygma exempta) and its control in South Africa.—Sci. Bull. Dep. Agric. S. Afr. no. 217, 50 pp.Google Scholar
Hunt, J. A. (1951). A general survey of the Somaliland Protectorate 1944–1950.—203 pp. London, Crown Agents.Google Scholar
Hurst, G. W. (1964). Meteorological aspects of the migration to Britain of Laphygma exigua and certain other moths on specific occasions.—Agric. Met. 1 pp. 271–281.CrossRefGoogle Scholar
Hurst, G. W. (1965). Laphygma exigua immigrations into the British Isles, 1947–1963.—Int. J. Biomet. 9 pp. 21–28.CrossRefGoogle Scholar
Hydrographer Of The Navy (1964). China sea pilot Vol. 1.—799 pp.London, Admiralty.Google Scholar
India Meteorological Department (1955). Indian daily weather report, 3–1906, 1955. Poona.Google Scholar
Jackson, C. H. N. (1941). The economy of a tsetse population.—Bull. ent. Res. 32 pp. 53–55.CrossRefGoogle Scholar
Jannone, G. (1948). Studi e ricerche di entomologia agraria in Eritrea e in Etiopia. VI.—Rassegna dei casi entomologici piu notevoli riscontrati in Eritrea durante il 1945.—Annali Fac. Agr. Univ. Pisa, 9 pp. 279–312.Google Scholar
Johnson, D. H. (1962). Rain in East Africa.—Q. Jl. R. met. Soc. 88 pp. 1–19.CrossRefGoogle Scholar
Johnson, D. H. (1965). African synoptic meteorology. In Meteorology and the desert locust. Proceedings of the WMO/FAO Seminar on Meteorology and the Desert Locust, Teheran, 25 November–11 December 1963.—Tech. Notes Wld met. Org. no. 69 pp. 48–90.Google Scholar
Johnson, D. H. & MÖrth, H. T. (1960). Forecasting research in East Africa. In Tropical meteorology in Africa.—Nairobi, Proc. WMO and Munitalp Symposium pp. 56–137.Google Scholar
Kapur, A. P. (1955). On moths of the greasy cutworm Agrotis ypsilon Rott. found dead in numbers on show over Rohtang Pass, N. W. Himalayas.—Indian J. Ent. 17 pp. 289–294.Google Scholar
Krogh, A. & Zeuthen, E. (1941). The mechanisms of flight preparation in some insects.—J. exp. Biol. 18 pp. 1–10.CrossRefGoogle Scholar
Laird, M. A. (1962). A flight of insects in the Gulf of Aden.—Proc. 11th Int. Congr. Ent. 1960, 3 pp. 35–36.Google Scholar
Larsen, E. B. (1949). Activity and migration of Plusia gamma L.—Biol. Meddr 21 pp. 1–32.Google Scholar
Lewis, T. & Taylor, L. R. (1965). Diurnal periodicity of flight by insects.—Trans R. ent. Soc. Lond. 116 pp. 393–469.CrossRefGoogle Scholar
Li, Kuang-Po, Wong, Hong-Hsiang & WOO, Wan-Sei (1964). The hypothetical injuriousness of the seasonal migrations of the oriental armyworm and experiments with the release and recapture of marked individuals. [In Chinese with English summary].—Acta phytophylac. sin. 3 pp. 101–110.Google Scholar
Lin, Ch’ang-Shan, SUN, Chin-Ju, Chen, Rui-Lo & Chang, J., Tsun-Ping (1963). Studies of the regularity of the outbreak of the oriental armyworm, Leucania separata Walker: I. The early spring migration of the oriental armyworm moths and its relation to winds. [In Chinese with English summary].—Acta ent. sin. 12 pp. 243–261.Google Scholar
Luginbill, P. (1928). The fall armyworm.—Tech. Bull. U. S. Dep. Agric. no. 34, 91 pp.Google Scholar
Mackie, D. B. (1932). Report of the Division of Entomology and Pest Control.—Mon. Bull. Calif. Dep. Agric. 20 pp. 745–761.Google Scholar
MatthÉe, J. J. (1952). The occurrence of the armyworm (Laphygma exempta (Walk.)) in and around Pretoria.—J. ent. Soc. sth Afr. 15 pp. 122–128.Google Scholar
Mel’nichenko, A. N. (1936). Regularities of mass flying of the adult ofLoxostege sticticalis L. and the problem of the prognosis of their flight migrations. [In Russian with English summary]—Trudy Zashch. Rast. (1) no. 17, 56 pp.Google Scholar
Mikkola, K. & Salmensuu, P. (1965). Migration of Laphygma exigua Hb. (Lep., Noctuidae) in north-western Europe in 1964.—Annls zool. fenn. 2 pp. 124–139.Google Scholar
Pearson, E. O. (1958). The insect pests of cotton in tropical Africa.—355 pp. London, Emp. Cott. Grow. Corp. & Commonw. Inst. Ent.Google Scholar
Pedgley, D. E. (1966). The Red Sea convergence zone.—Weather 21 pp. 350–358, 394–406.CrossRefGoogle Scholar
Pyenson, L. (1940). The cotton leafworm in the western hemisphere.—J. econ. Ent. 33 pp. 830–833.CrossRefGoogle Scholar
Rainey, R. C. (1947). Observations on the structure of convection currents; meteorological aspects of some South African gliding flights.—Q. Jl. R. met. Soc. 73 pp. 437–452.CrossRefGoogle Scholar
Rainey, R. C. (1951). Weather and the movements of locust swarms: a new hypothesis.—Nature, Lond. 168 pp. 1057–1060.CrossRefGoogle Scholar
Rainey, R. C. (1958). Some observations on flying locusts and atmospheric turbulence in eastern Africa.—Q. Jl. R. met. Soc. 84 pp. 334–354.CrossRefGoogle Scholar
Rainey, R. C. (1962). Some effects of environmental factors on movements and phase-change of locust populations in the field.—Colloques int. Cent. natn. Rech. Scient. 114 pp. 175–199.Google Scholar
Rainey, R. C. (1963). Meteorology and the migration of desert locusts: applications of synoptic meteorology in locust control. (Abstr.)—Tech. Notes Wld met. Org. no. 54/Anti-Locust Mem. no. 7, 115 pp.Google Scholar
Rainey, R. C. (1965). The origin of insect flight: some implications of recent findings from palaeoclimatology and locust migration. (Abstr.)—Proc. 12th int. Congr. Ent. 1964. p. 134.Google Scholar
Rainey, R. C. (1967). A note on some migrations of moths and locusts.—Israel J. Ent. 2 pp. 187–189.Google Scholar
Rainey, R. C. & Aspliden, C. I. H. (1963). The geographical distribution and movements of desert locusts during 1954–55 in relation to the corresponding synoptic meteorology. Tech. Notes Wld. met. Org. no. 54 pp. 54–103.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
Ramakrishna Ayyar, T. V. & Anantanarayanan, K. P. (1935). Agricultural meteorology in its relation to insect pests.—Madras agric. J. 23 pp. 328–335.Google Scholar
Ramsey, B. (1966). Low level wind flow at Nairobi.—Met. Mag., Lond. 95 pp. 47–57.Google Scholar
Rivnay, E. (1964). A contribution to the biology and phenology of Agrotisyspsilon Rott. in Israel.—Z. angew. Ent. 53 pp. 295–309.CrossRefGoogle Scholar
Rivnay, E. & Yathom, S. (1964). Phenology of Agrotinae in Israel.—Z. angew. Ent. 55 pp. 136–152.CrossRefGoogle Scholar
Roffey, J. (1963). Observations on night flight in the desert locust (Schistocerca gregaria Forskål).—Anti-Locust Bull. no. 39, 32 pp.Google Scholar
Rungs, C. (1946). Rapport sur les essais de lutte contre les adultes de Schistocerca gregaria Forsk. au Maroc français au printemps de 1945.—Bull. semest. Off. natn. anti-acrid. 2 pp. 41–87.Google Scholar
de Meteorologia, Servicio, de Janeiro, Rio (1966). Boletim diario do tempo. nos. 152–162.Google Scholar
Smit, B. (1964). Insects in southern Africa: how to control them.—399 pp. Cape Town, O.U.P.Google Scholar
South African Meteorological Office (1941). Atmospheric pressure and weather charts.—84 pp. 26 figs. Pretoria, Irrigation Dep.Google Scholar
Taylor, L. R. (1960). The distribution of insects at low levels in the air.—J. Animal Ecol. 29, pp. 45–63.CrossRefGoogle Scholar
Thompson, B. W. (1951). An essay on the general circulation of the atmosphere over south-east Asia and the west Pacific.—Q. Jl R. met. Soc. 77. pp. 569–597.CrossRefGoogle Scholar
Thompson, S. W. (1965). The climate of Africa.—132 pp. Oxford Univ. Pr.Google Scholar
Tschirhart, G. (1959). Les perturbations atmosphériques intéressant l’ A.E.F. méridionale.—Monogrs Mét. nata. no. 13 pp. 1–32.Google Scholar
United States Weather Bureau. (1937). Daily synoptic series: sea-level historical weather maps, 26 05, 1937. Washington, D.C.Google Scholar
Uvarov, B. P. (1957). The aridity factor in the ecology of locusts and grasshoppers of the Old World. In Arid Zone Research: VIII Human and animal ecology. Reviews of Research, pp. 164–198. Paris, UNESCO.Google Scholar
Vickery, R. A. (1929). Studies on the fall armyworm in the Gulf Coast district of Texas.—Tech. Bull. U.S. Dep. Agric. no. 138, 64 pp.Google Scholar
Wallace, A. R. (1886). The Malay archipelago.—653 pp. London, Macmillan.Google Scholar
Waloff, Z. (1946). Seasonal breeding and migrations of the desert locust (Schistocerca gregaric Forskål) in eastern Africa.—Anti-Locust Mem. no. 1, 74 pp.Google Scholar
Waloff, Z. (1963). Field studies on solitary and transiens desert locusts in the Red Sea area.—Anti-Locust Bull. no. 40, 93 pp.Google Scholar
Waloff, Z. (1966). The upsurges and recessions of the desert locust plague: an historical survey.—Anti-Locust Mem. no. 8, 111 pp.Google Scholar
Waloff, Z. & Rainey, R. C. (1951). Field studies on factors affecting the displacements of desert locust swarms in eastern Africa.—Anti-Locust Bull. no. 9, 50 pp.Google Scholar
Weis-Fogh, T. (1956). Biology and physics of locust flight. II. Flight performance of the desert locust (Schistocerca gregaric).—Phil. Trans. R. Soc. 239 pp. 459–510.Google Scholar
Whellan, J. A. (1954). The African armyworm and its control.—Rhod. agric. J. 51 pp. 415–427.Google Scholar
Willcox, F. C. & Bahgat, S. (1937). The insect and related pests of Egypt vol. 1 pt. 2. Insects and mites injurious to the cotton plant.—792 pp., 14 pls. Cairo, R. agricultural Soc.Google Scholar
Williams, C. B. (1937). The use of logarithms in the interpretation of certain entomological problems.—Ann. appl. Biol. 24 pp. 404–414.CrossRefGoogle Scholar
Williams, C. B. (1958). Insect migration.—235 pp. London, Collins.Google Scholar
World Meteorological Organization. (1953). Document 36 (I-RAI), In Final report on the first session of the Regional Association for Africa, Tananarive (Madagascar), 19–30th 01 1953, pp. 166–174.Google Scholar