An Empirical Test of Community Stability: Resistance of a Fouling Community to a Biological Patch‐Forming Disturbance

Abstract

Stability, defined as resistance to external perturbation, was evaluated for two developmental stages of an estuarine subtidal fouling community subjected to a biological patch—forming disturbance. Three stability criteria: (1) magnitude of response, (2) rate of response, and (3) recovery, were assessed on the basis of differences between control and perturbed panel communities with respect to physical structure (percent bare substrate, and sessile species volume), species richness (S), evenness (VH'), interaction diversity (H'), and community similarity, over time. Both motile and sessile species assemblages were examined, and responses of individual species were also determined. The older fouling community was found to be less stable than the younger one in terms of both measures of physical structure, for all three stability criteria. This was also true for species richness. Differences in evenness and H' between control and perturbed communities showed no consistent trend in this regard, and motile and sessile species exhibited different degrees of response. Multiple discriminant analysis indicated that fewer species contributed to the discriminant function in the younger community than in the older one. Community similarity between control and perturbed panel communities was lower overall for the older community. Individual species responses that contributed to these effects were examined. The results of our study, as well as an examination of other empirical evidence from the literature, reveal a lack of consistent support for traditional hypotheses of community stability. We conclude that evolutionary pressures, and resulting ecological strategies, are more important in determining community resistance stability than statistical properties such as species diversity.

Community stability, complexity and species life history strategies

“…Our case study represents simple kinds of plant communities only, and conclusions must therefore be taken with caution. Nevertheless, presented interpretation is in agreement with recent critical reevaluations (see Marks, 1974;Sousa 1980;Smedes & Hurd 1981) of the trends and mechanisms of successional changes in plant and animal communities.…”

Habitat Isolation Reduces the Temporal Stability of Island Ecosystems in the Face of Flood Disturbance

“…Combined with the decline in species richness with habitat isolation, this finding offers rare support for the theoretical negative relationship between diversity and resilience proposed by Loreau and Behera (1999). Similar empirical results have been shown for successional diversity gradients in estuarine fouling (Smedes and Hurd, 1981) and old-field plant (Lepš et al, 1982) communities, highlighting the importance of speed of community re-assembly for promoting stability in natural systems.…”

Short-term dynamics of tropical macroalgal epifauna: patterns and processes in recolonisation of Sargassum fissifolium

“…The stability of a community can be evaluated by its response to experimental perturbation (e.g. Smedes & Hurd 1981, Farrell 1988.…”

“…However, such communities normally display predictable cycles of abundance (Edgar 1983a, Arrontes & Anadon 1990, Martin-Smith in press) implying high community stability. Whilst epifaunal populations have been shown to rapidly colonise defaunated substrata (Gunnill 1982, Edgar 1983b, Stoner 1985, Virnstein & Curran 1986), this has not usually been set against the dynamic background of changes in unmanipulated communities (Smedes & Hurd 1981, Karlson & Hurd 1993. Furthermore, such studies have almost invariably been carried out in northern hemisphere temperate or subtropical areas (but see Stoner 1985) where the frequency and intensity of disturbance may be very different to that in the tropics (Pickett & White 1985).…”