Insect Herbivores, Herbivory and Plant Succession

Abstract

Succession is a characteristic feature of most plant communities and is clearly seen when any habitat is disturbed. The temporal and directional changes in plant communities, which constitute succession, are well documented and have been described in a range of different habitats and geographical regions (e.g. Oosting 1942; Beckwith 1954; Olson 1958; Bazzaz 1968; Tramer 1975; Southwood et al. 1979; Brown and Southwood 1987). Accounts of the associated changes in animal communities are much rarer and there are relatively few studies spanning a period of several years or even comparing habitats of different successional age (but see Southwood et al. 1979; Fox and Fox 1986; Brown and Southwood 1983, 1987). Invertebrates, and especially insects, are more amenable to a quantified sampling programme at different stages of succession than are some organisms (e.g. birds) and can therefore be compared between habitats (Brown et al. 1988a) or even in geographical regions (see Brown et al. 1987b). Although patterns of insect abundance through time are in themselves interesting, it is an understanding of their interaction with the plant community which can contribute to further insight into the mechanisms underlying plant succession. It is well known that large vertebrate herbivores can have a substantial impact on vegetation dynamics (e.g. Watt 1960; Gibson et al. 1987). However, invertebrate herbivory has only recently been considered in this context.