We present a model of community regulation that incorporates the effects of abiotic disturbance, predation, competition, and recruitment density. We assume that mobile organisms (i.e., consumers) are more strongly affected by environmental stress than are sessile organisms and that food-web complexity decreases with increasing stress. The model makes three predictions under conditions of high recruitment. First, in stressful environments, consumers have no effect because they are absent or inactive, and competition for space is prevented. Both mobile and sessile organisms are regulated directly by environmental stress. Second, in moderate environments, consumers are still ineffective, but sessile organisms are less affected by stress and frequently attain high densities, leading to competition for space. Finally, in benign environments, consumers prevent competition for space unless the prey can escape a predation bottleneck and reach a high abundance. A reduction in recruitment density reduces the import...

Community regulation: variation in disturbance, competition, and predation in relation to environmental stress and recruitment

In the laboratory, the swimming larvae of benthic marine invertebrates are generally capable of prolonging their larval period beyond the time that they first become physiologically competent to metamorphose. Larvae seem to differ markedly in their ability to postpone metamorphosis, both interspecifically and intraspecifically. The proportion of this variability that is genetically controlled has not yet been determined; if under genetic control, both pre-competent and competent periods would be subject to selection, although the selective pressures and the physiological or developmental mechanisms through which such pressures might operate remain purely speculative. Limited data strongly suggest that at least a few species delay metamorphosis in the field. The frequency with which they do so, and under what conditions they do so, and for how long, are unexplored questions. Some of these issues can now be explored, with the finding that various inorganic and organic substances can trigger the met...

Delayed metamorphosis by larvae of benthic marine invertebrates: Does it occur? Is there a price to pay?

Recruitment and metamorphosis of Haliotis larvae induced by molecules uniquely available at the surfaces of crustose red algae

The methodologies applied in laboratory and field studies of the effects of biofilm cues on marine invertebrate larval settlement on hard substrata are briefly reviewed and some of the general problems (such as experimental repeatability, handling effects) that may be encountered, and the ecological representativeness of the species utilized are discussed. The review focuses also on the range of bioassay approaches and highlights the wide range of larval densities, substrata and biofilm sources that have been variously applied. It is important to consider all of these features in any attempt at formulating general principles and trends relating to larval settlement responses in natural assemblages. This review also highlights the prevalence of reports of facilitatory, rather than neutral or inhibitory, effects amongst the various species investigated and considers the possible role(s) of larva‐larva interactions, cue perception distances, hierarchical effects and whether or not biofilm cues are surface‐bo...

Inhibition and facilitation of settlement of epifaunal marine invertebrate larvae by microbial biofilm cues

The control of the development of a marine benthic community by predation on recruits

Observations on the settlement of the brachiolaria larvae of Stichaster australis (Verill) and Coscinasterias calamaria (Gray) (Echinodermata: Asteroidea) in the laboratory and on the shore

Breeding and recruitment in a population of the New Zealand starfish Stichaster australis (Verrill)

Structure of the organs of attachment of brachiolaria larvae of Stichaster australis (Verrill) and Coscinasterias calamaria (Gray) (Echinodermata: Asteroidea)

M.F. Barker

Papers

Observations on the settlement of the brachiolaria larvae of Stichaster australis (Verill) and Coscinasterias calamaria (Gray) (Echinodermata: Asteroidea) in the laboratory and on the shore

Breeding and recruitment in a population of the New Zealand starfish Stichaster australis (Verrill)

Structure of the organs of attachment of brachiolaria larvae of Stichaster australis (Verrill) and Coscinasterias calamaria (Gray) (Echinodermata: Asteroidea)