Succession in a stream invertebrate community: A transition in species dominance through colonization

Abstract

A field experiment was conducted using ceramic plates as experimental substrates to describe the colonizing pattern of a stream invertebrate community after disturbance, and to ascertain the importance of colonizing ability for succession in a Japanese stream. We employed the simultaneous removal design in which plates were periodically set in place (1, 2, 4, 8, 16 and 32 days before sampling) and all plates were sampled on the last day of the experiment, to diminish the influence of seasonal change in stream invertebrates. Total abundance and taxon richness reached a plateau after 4–16 days of colonization. In contrast, the relative abundance of six common taxa and community structure changed throughout the 32 days of colonization. Differences in the colonizing ability of the stream invertebrates were evident. Taxa with high mobility, such as the mayflies Baetis thermicus, Paraleptophlebia japonica, Cinygmula sp. and Drunella sachalinensis, colonized faster than those with low mobility (e.g. the caddisfly species Brachycentrus americanus and the chironomid midge Diamesinae spp.). The abundance of the most common taxon, Baetis, decreased at late stages of colonization, possibly because of low periphyton biomass. Consequently, we concluded that a difference in colonization ability among taxa is an important factor causing succession in stream invertebrate communities in local habitats.