Interference Competition and the Coexistence of Two Competitors on a Single Limiting Resource

Abstract

This p~per proposes a mechanistic model of competition between two species for a smgle, ~onaccumulatmg foo~ resource. Actual organisms to which it may apply are sessile species like terrestnal plants and suspension-feeding benthic marine invertebrates whose energy source rains down ~pon ~em from t.he surrounding environment. The model's assumptions describe general functions mv~lvmg populatiOn growth, resource consumption, resource availability, and interference. The pop-ulatiOn consequences of competition thereby arise in a specified way from the properties of individual organisms. The generality of the various component functions allows them to accommodate a wide range of species' morphological, physiological, and behavioral properties as well as relevant features ?fthe physical environment. Accordingly, the overall model potentially approximates a correspond-Ingly broad array of natural cases of competition.This model demonstrates the theoretical possibility that two species jointly limited by the same energy resource can coexist at a globally stable equilibrium point. The proof of this assertion involves standard isocline analysis. It reveals that, in this case, coexistence depends upon species' interference as well as resource exploitation properties. In particular, the two can coexist if each species interferes ~ess with resource acquisition by the other than with resource acquisition by itself and if this difference IS great enough to overwhelm the advantage of the more efficient exploitation competitor.The model includes the effects of space competition and abiotic disturbances. Field testing is discussed.

Coexistence in competition models with density-dependent mortality

“…To have the strong version of coexistence, researchers have taken various other factors into account when modeling competition, such as interspecific interference [45,46], spatial heterogeneity [5], stoichiometric principles [34], etc. Another important factor is intraspecific interference within a population of competitors, which includes aggressive displays, posturing, fighting, infanticide, and cannibalism [30].…”

Interference competition and species coexistence

“…Interference competition involves direct negative interactions arising from territoriality, overgrowth, undercutting, predation or chemical competition (Schoener 1983). Each consumer alters others' ability to exploit the resource at any level of abundance (Vance 1984).…”

Competition and stoichiometry: coexistence of two predators on one prey

“…Second, even for models that explicitly consider resources, the coexistence of n species on fewer than n resources is possible via internally produced limit cycles (Armstrong and McGehee, 1976;Abrams and Holt, 2002) or chaotic fluctuations (Armstrong and McGehee, 1980;Weissing, 1999, 2000). Third, other factors such as spatial (Durrett and Levin, 1994;Richards et al, 2000) or temporal (Butler et al, 1985;Lenas and Pavlou 1995;Chesson, 1994) heterogeneity, light fluctuations (Litchman and Klausmeier, 2001), predation (Holt and Lawton, 1994;Leibold, 1996;Chase et al, 2002), disturbance (Hastings, 1980), and interference between consumers (Vance, 1984(Vance, , 1985Kuang et al, 2003) provide mechanisms for coexistence.…”