title: Importance of competition mechanisms in successive invasions by polyphagous tephritids in La Reunion.
abstract: Understanding the strength and modes of interspecific interactions between introduced and resident species (native or previously introduced) is necessary to predict invasion success. We evaluated different mechanisms of interspecific competition among four species of polyphagous fruit flies (Diptera: Tephritidae) from the island of La Reunion: one endemic species, Ceratitis catoirii, and three exotic species, C. capitata, C. rosa, and Bactrocera zonata, that have successively invaded the island. Larval competition experiments, i.e., co-infestations of the same fruit, and behavioral interference experiments measuring the ability of one female to displace another from a fruit, were performed among all pairs of the four species. We observed asymmetric and hierarchical interactions among species in both larval and adult interference competition. In agreement with the hypothesis that invasion is competition-limited, the competitive hierarchy coincided with the temporal sequence of establishment on the island, i.e., each newly established species tended to be competitively dominant over previously established ones.
authors.affiliation: UMR 53 Peuplements Végétaux et Bio-agresseurs en Milieu Tropical CIRAD Pôle de Protection des Plantes (3P), 7 chemin de l'IRAT, 97410 St Pierre, La Réunion, France. duyck@cirad.fr
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Duyck
authors.forename: Patrice
authors.initials: P
authors.lastname: David
authors.forename: Guillemette
authors.initials: G
authors.lastname: Junod
authors.forename: Caroline
authors.initials: C
authors.lastname: Brunel
authors.forename: Raphaël
authors.initials: R
authors.lastname: Dupont
authors.forename: Serge
authors.initials: S
authors.lastname: Quilici
mesh_terms: D000818:Animals; D017753:Ecosystem; D005260:Female; D005638:Fruit; D007814:Larva; D011157:Population Dynamics; D011679:Pupa; D017508:Reunion; D013045:Species Specificity; D033621:Tephritidae / Q000502:physiology*