Abstract
The terminal velocity of first instarEctropis excursaria, determined in a part mechanical part electrical apparatus, were 114±12 cm/s and 118±12·5 cm/s for two different heights. Terminal velocity decreased exponentially with increased silk lengths. For a given length of silk there wsa a significant difference in the terminal velocity of live and anaesthetised insects. The significance of these results to the understanding of the wind dispersal of first instar caterpillars is discussed.
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References
Arbas E A 1983 Aerial manoeuvring reflexes in flightless grasshoppers;J. Exp. Biol. 107 509–513
Batzer H O 1968 Hibernation site and dispersal of spruce budworm larvae as related to damage to sapling balsam fir;J. Econ. Entomol. 61 216–220
Boykin L S and Campbell W V 1984 Wind dispersal of the two spotted spider mite (Acari: Tetranychidae) in North Carolina peanut fields;Environ. Entomol. 13 221–227
Cohn T and Cantrall I J 1974 Variation and speciation in the grasshoppers of the Conalcaeini (Orthoptera: Melanoplinae): The lowland forms of Western Mexico, the Genus Barytettix,San Diego Soc. Nat. Hist. Mem. 6 1–13
Harrington J B 1979 Deposition principles of microbiological particles; inAerobiology—The Ecological Systems Approach (ed.) R L Edmonds (New York: Academic Press) pp 112–145
Jennings D T, Houseweart M W and Dimon J B 1983 Dispersal losses of early first instar spruce budworm (Lepidoptera: Torticidae) larvae in strip, clearcut and dense spruce-fir forests of Maine;Environ. Entomol. 12 1787–1791
Leonard D E 1974 Recent developments in the ecology and control of the gypsy moth;Annu. Rev. Entomol. 19 197–230
Mason C J and McManus M L 1979 The role of dispersal in the natural spread of the gypsy moth;Proc. of the II IUFRO conference on Dispersal of forest insects: Evaluation, theory and management implications (eds) E A Berryman and L Safranyik (Pullman: Wash. State Univ. Coop. Ext. Serv.) pp 94–115
McManus M L and Mason C J 1983 Determination of settling velocity and its significance to larval dispersal of the gypsy moth (Lepidoptera: Lymantridae);Environ. Entomol. 12 270–272
Mitchell R G 1979 Dispersal of early instars of Douglas-fir Tussock moth;Ann. Entomol. Soc. Am. 72 291–297
Moran V C, Gunn B H and Walter G H 1982 Wind dispersal and settling of first instar crawlers of cochineal insectDactylopius austrinus (Homoptera: Dactylopiidae);Ecol. Entomol. 7 409–419
Ramachandran R 1987 Host-plant influences on the wind dispersal and survival of the first instars of an Australian Geometrid caterpillar;Entomol. Exp. Appl. (in press)
Washburn J O and Frankie G W 1981 Dispersal of a scale insectPulvinariella mesembryanthemi (Homoptera: Coccoidea) on ice-plant in California;Environ. Entomol. 10 724–727
Washburn O and Washburn L 1984 Active aerial dispersal of minute wingless arthropods: Exploitation of boundary layer velocity gradients;Science 223 1088–1089
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Ramachandran, R. Terminal velocity of the first instarEctropis excursaria (Guenee) (Lepidoptera: Geometridae). Proc. Indian Acad. Sci. (Anim. Sci.) 96, 673–678 (1987). https://doi.org/10.1007/BF03179497
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DOI: https://doi.org/10.1007/BF03179497