TO CONTROL OR NOT TO CONTROL: WHEN THE ECOLOGICAL COSTS OF MANAGEMENT-DRIVEN PHENOTYPIC CHANGES COUNTERBALANCE THE BENEFITS OF INVASIVE SPECIES REMOVAL
Across the globe, large-scale eradication programs aiming at controlling invasive species are implemented and they represent a unique opportunity to assess the effects of harvest-driven trait changes on ecosystem functioning. Indeed, intraspecific variability is now widely recognised as a key driver of ecological dynamics and, by inducing a non-random removal of individuals from targeted populations, control programs might modify trait distribution in managed populations and, subsequently, ecosystem functioning. Harvest-driven trait changes in invasive species might induce unexpected and potentially counterproductive results that are not explicitly considered by scientists and managers. Using invasive freshwater fish and crayfish as model organisms, the present study aimed at assessing the efficiency of control programs by quantifying managed-induced phenotypic trait changes in invasive species along a gradient of management practices and comparing the effects of population size reduction versus harvest-driven trait changes. Field observations first revealed the existence of significant changes in a suite of phenotypic traits of functional importance between populations. We then demonstrated using experimental mesocosms that the ecological gains achieved by removal (i.e. reduction in invasive species density) could be substantially reduced by management-induced phenotypic changes.
Libor Zavorka (Co-Presenter/Co-Author), Toulouse Univeristy, France, Libor.Zavorka@glasgow.ac.uk;
Iris Lang (Co-Presenter/Co-Author), Toulouse Univeristy, France, firstname.lastname@example.org;
Bastien Jorigne (Co-Presenter/Co-Author), Toulouse University, France, email@example.com;
Remy Lassus (Co-Presenter/Co-Author), Toulouse University, France, firstname.lastname@example.org;
Julien Cucherousset (Primary Presenter/Author,Co-Presenter/Co-Author), CNRS, Toulouse University, Dept EDB, France, email@example.com;