Reply to comments by Gurvich et al. (2016) on “Fruiting phenology as a ‘‘triggering attribute’’ of invasion process: Do invasive species take advantage of seed dispersal service provided by native birds?”

Abstract

In 2005, Gurvich et al. proposed that once a nonindigenousspecies has arrived to a new ecosystem andbecome established, the likelihood that it spreads, andthus becomes invasive, may depend on just one or veryfew characteristics, called ?triggering attributes? (TA).We propose that a TA is a vegetative or regenerativeattribute discontinuously distributed in comparison tothe resident community. This attribute allows thespecies to benefit from a resource that is permanentlyor temporarily unused by the resident community. The winter fruit phenology of two fleshy fruitedinvaders (P. angustifolia and Ligustrum lucidum) wasproposed as an example of TA that would allow thesetwo species to take advantage of a resource (birddispersal) that resident fleshy-fruited species?whosefruits are ripe in summer and autumn cannot tapduring the winter (Gurvich et al. 2016). We believethat the model they proposed is a very valuable one,and useful to identify special traits involved in plantinvasion processes. In a recent response to an articlethat evaluates if a vegetative attribute behaves as a TA(Vergara-Tabares et al. 2015), Gurvich et al. (2016)expressed disagreement regarding the logic used todevelop the experimental design and the main conclusionsof the study. The arguments of Gurvich et al.(2016) demonstrate some misinterpretation of thestudy and its results, and we believe it deservesclarification.