AGRICULTURAL RESEARCH COMMUNICATION CENTRE www.arccjournals.com *Corresponding author’s e-mail: sujayanand_agri@yahoo.co.in. 1 Division of Crop Protection, Indian Institute of Pulses Research, Kanpur-208024. 2 Directorate of onion and garlic Research, Pune-410505. Agricultural Reviews, 37 (3) 2016 : 221-227 Print ISSN:0253-1496 / Online ISSN:0976-0539 Aftermath of climate change on insect migration: A review G.K. Sujayanand* 1 and V. Karuppaiah 2 Division of Crop Protection, Indian Institute of Pulses Research, Kanpur-208 024, India. Received: 26-05-2015 Accepted: 14-07-2016 DOI: 10.18805/ag.v37i3.3537 ABSTRACT Climate change is inflicting a huge impact in all the corners of biosphere. The insects, one of the early inhabitants of the biosphere are well known for their co-evolution with the plants and adaptation to the diverse environments. The power of flight makes the insect community to occupy new habitats and hence insect migration is one of the predominant areas for investigation in the perspective of climate change. The insect migration is a complex science that involves thorough understanding of insect bio-ecology along with knowledge of meteorology, aerodynamics, remote sensing and climatology. The various abiotic parameters that influence the insect migration and the effects of these parameters under the changing climatic scenario are discussed in this paper. Key words: Climate change, Insect migration. The first record of insect existence came from the Devonian period (i.e. 500 million years ago). The first flying insect was traced to the carboniferous period (i.e. 354 to 295 million years ago). The insects can occupy new habitats and niches where other species cannot occupy by through their unique ability of flight. The flight is used by insects for dispersal and migration from one place to other to accomplish the biological needs such as host finding, mating etc. Migration refers to a continued movement in a more or less definite direction, in which both movement and direction are under the control of the animal concerned (Williams, 1957). Migration refers to transfer of population from place to place by mass flights (Johnson, 1969). Migratory behavior is persistent and straightened-out movement effected by the animal’s own locomotory exertions on or by its active embarkation on a vehicle. It depends on some temporary inhibition of station-keeping responses, but promotes their eventual disinhibition and recurrence (Kennedy, 1985). Dispersal is more simply defined as movement that results in an increase in the mean distance between individuals. Insects are among the groups of organisms which are most likely to be affected by climate change because climate has a strong direct influence on their development, reproduction and survival (Bale et al., 2002). The fourth annual assessment report of IPCC predicts an average Surface temperature increase from 1.1 to 5.4ºC by 2100 (Meehl et al., 2007). One of the reasons for this climate change is increase in anthropogenic CO 2 emission. Insects respond quickly to this climate change as they need a particular temperature preferendum to complete its life cycle. Insect has the unique ability to fly and colonize new habitat. Movement not directly responsive to a resource or home range Movement Directed by resources and/or home range A. Station keeping (foraging, commuting) B. Ranging (to explore an area, often for a new home range) Migration is a type of movement displayed by insects, but it differs from all other types because migratory insects (and other migrants as well) are unresponsive to suitable resources. There are two broad categories of movements: Insects and climate change: Insects are cold-blooded organisms i.e. the temperature of their bodies is approximately the same as that of the environment. Therefore, the external environment influences the insect’s key physiological processes very much. Temperature is probably the single most important environmental factor influencing insect behaviour, distribution, development, survival, and reproduction. Insect life stage predictions are most often calculated using accumulated degree days from a base temperature. The effect of temperature on insects largely overwhelms the effects of other environmental factors (Bale et al., 2002). It has been estimated that with a 2 o C temperature increase insects might experience one to five additional life cycles per season (Yamamura and Kiritani 1998). Apart from temperature, moisture and CO 2 effects on insects can be potentially important considerations in a global climate change scenario (Coviella and Trumble 1999).