Lotic meiofaunal community dynamics: colonisation, resilience and persistence in a spatially and temporally heterogeneous environment

Abstract

1. The spatial and temporal dynamics of lotic meiofaunal communities were examined with a focus on colonisation, maintenance of populations in lotic environments and persistence of meiofaunal communities.2. Lotic meiofaunal colonisation of new habitats may take place via a number of mechanisms and is rapid at both the patch scale (within hours–days) and the drainage basin scale (within 20 years). Successional patterns in lotic meiofaunal communities are evident although data are extremely limited.3. Lotic meiofaunal communities appear to be resilient to high flow disturbances. Resilience is moderated by the availability of in‐stream refugia and habitat hydrology. Lotic meiofauna may also adopt a ‘refuge as habitat‘ approach to such disturbances.4. Lotic cyclopoid copepods possess a common suite of life history characteristics that confers resilience to disturbances. Compared to pelagic planktonic species they have short generation times, many descendants per reproductive cycle and long lifespans. Females in ‘source‘ populations are likely to survive disturbances and so could continuously reproduce over a long period of time producing large numbers of offspring which develop rapidly and recolonise ‘sink‘ areas of the stream.5. Persistence of lotic meiofaunal communities is highly variable. Meiofaunal persistence does not increase with increasing proportions of in‐stream flow refugia.