Migration and Meteorology

This book surveys research into migrant pests such as the desert locust, and how their movements relate to the dynamics of wind and weather systems. The author describes how the often erratic movements of the pests, which can be catastrophic to crops, can now be mapped with radar. Their flight behaviour is described, and the ecological and evolutionary aspects of flight and migration are discussed aiming to present new options for the strategy and tactics of pest management, especially in relation to the African locust and grasshopper. By examining what has been achieved in this area, the author has provided for the biologist an introduction to the relevant aspects of meteorology.Table of ContentPart 1 The desert locust - prototype migrant: locust control and migration - the background; locust migration - facts and mechanisms; biology and behaviour of the desert locust in relation to migration; displacements of discrete locust populations; locust migration, winds and weather on the intercontinental scale - the desert locust and synoptic meteorology; locust numbers - the evidence and the problem of control; the assessment of locust numbers and of control operations; locusts at a low ebb - continuity of recession populations; swarming and solitary phases; outline of a recession - treatment of data; - findings; experience of recession forecasting; current status of the Phase Theory. Part 2 Flight and migration in other major pests; armyworms - larvae of formidably migrant moths; sample of the armyworm problem - Sierra Leone 1979; trans-equatorial sequences of armyworm attack; analogies with locusts; establishing the timing and spacing of infestations in relation to the distribution of the moths; forecasting in East Africa; infestations - incursions of westerly winds and other early evidence; moth flight - from circumstantial evidence to radar observations and marking/capture; possible antecedents of armyworm attacks in West Africa - squall-line studies for WHO/ONCHO and other clues; armyworm control - current approaches and some future possibilities; spruce budworm - major forest problem of North America; the background - problems of the economy and the environment; budworm moth flight - observations by radar and aircraft. Part 3 Management of migrant pests - prospects and options, some suggestions: problems of the desert locust and other locusts of Africa; African armyworm - prospects and options; spruce budworm - prospects and options; major migrant pests in China - possible new options for monitoring and control; migrant pests and "nuclear winter". Part 4 Ecology and evolution of insect flight and migration - some implications from findings on migrant pests; survival value of systems of downwind redistribution; migration - a single strategy implemented by a range of alternative tactics; evolution of insect flight; migration without navigation; navigation in static populations - the honey-bee. Appendices Further notes on applications of meteorology in investigations of airbourne migration: 1 - some points of meteorological observation and analysis, surface and upper air; 2 - problems of observation and interpretation of field/phenomena - some analogies from meteorological procedures; 3 - hour-to-hour movements of individual swarms in relation to wind.