Spatial distribution and the effects of competition on some temperate Scleractinia and Corallimorpharia

Abstract

The impact of interference competition on coral community structure is poorly understood. On subtidal rocks in the northeastern Pacific, members of 3 scleractinian coral species (Astrangia lajollaensis, Balanophyllia elegans, Paracyathus stearnsii) and 1 corallimorpharian (Corynactls californica) were examined to determine whether competition exerts substantial influence over t h e~r abundance and distributional patterns. These anthozoans occupy > 50 % cover on hard substrata, and exhibit characteristic patterns of spatial distribution, with vertical zonation and segregation among some species. They interact in an interspecific dominance hierarchy that lacks reversals, and is linear and consistent under laboratory and field conditions. Experiments demonstrated that a competitive dominant, C. californica, influences the abundance and population structure of a subordinate. B. elegans, by ( 1 ) reducing sexual reproductive output, (2) increasing larval mortality, (3) altering recruitment patterns. Field cross-transplants revealed that the dominant also affects vertical zonation of a competitive intermediate, A. lajollaensis, by lulling polyps that occur near the tops of subtidal rocks. It is concluded that between-species competition, mediated in part by larval-adult ~nteraction, strongly influences the structure of this temperate anthozoan assemblage.

Competitive interactions among zoanthids (cnidaria: zoanthidae) in an intertidal zone of northeastern Brazil

“…Previous studies have investigated competition processes among many invertebrates such as sponges (ABDO et al, 2008;LUTER;DUCKWORTH, 2010), ascidians (SHENKAR;SHENKAR et al, 2008), Bryozoans (TURNER;TODD, 1994) and cnidarians (LANG, 1973;JACKSON;BUSS, 1975;SHEPPARD, 1979SHEPPARD, , 1985KARLSON, 1980;SAMMARCO et al, 1985;SHEPPARD, 1985;DAI, 1990;ROMANO, 1990;CHADWICK, 1991;ALINO et al, 1992;FRANK et al, 1995;BASTIDAS;BONE, 1996; VAN VEGHEL et al, 1996;RINKEVICH;SAKAY, 2001;CONNELL et al,. 2004;RINKEVICH, 2004).…”

Are vertical distribution patterns of scleractinian corals maintained by pre- or post-settlement processes? A case study of three contrasting species

“…Differences among species of corals in tolerances to several physical factors (wave energy, currents, desiccation, light, temperature and sedimentation) are thought to determine the upper and/or lower limits of species depth distnbutions (Done 1982, Sheppard 1982, Sebens & Done 1992. Biological factors (competition and predation) have also been suggested as important controls on the depth distributions of corals (Glynn 1976, Sheppard 1982, Huston 1985, Chadwick 1991, although the widespread importance of biological controls for depth distributions of corals on tropical reefs has yet to be demonstrated. Previous attempts to unravel the processes underlying vertical zonation of tropical corals have focused primarily on factors affecting mature, coral populations (reviewed by Sheppard 1982), and with few exceptions (e.g.…”

Uneven abundance of the invasive sun coral over habitat patches of different orientation: An outcome of larval or later benthic processes?

“…Thus, biological interaction can alter local physical regimes which in turn can determine adult coral distribution. Other factors commonly recognized as determinants of coral recruitment are competition for space (Chadwick, 1991;Glynn, 1976;Sheppard, 1979), exogenous chemical signals (de Nys et al, 1991;Heyward and Negri, 1999;Koh and Sweatman, 2000), and disturbance by grazers (Lirman, 2001;Sammarco, 1980;Sammarco and Carleton, 1981). One of the few field experimental studies attempting to evaluate the importance of biological interactions on the sun coral distribution conducted in Brazil concluded that predation on Tubastraea spp.…”