Modelling the growth of the clonal invasive plant Carpobrotus sp.: A management approach

• Management of invasive species should be a priority in conservation policy • We develop a predictive model for control of two species of the invasive Carpobrotus • The model test different habitats invaded and the costs of using different methods • The model provides managers with important information for decision making • Early detection is key allowing mechanical eradication at an affordable cost Biological invasions are considered of the most serious threats to global biodiversity, with considerable economic costs being a consequence. The efficient management of these harmful species should therefore be considered a priority in conservation policy. As invasive species proliferate and new species arrive in a region, control costs are expected to increase, making the improvement of prevention and management strategies mandatory. The objective of this study is to develop a predictive model to facilitate the management of two invasive species of the genus Carpobrotus . A comprehensive understanding of the expansion patterns of a particular population is essential for the selection of suitable management strategies. The model developed in this study indicates that chemical control is the most economically efficient method. Conversely, methods involving manual removal of plant material implicate a greater number of working hours, and therefore a higher economic cost. For all three methods evaluated (mechanical removal, chemical treatment, chemical treatment with necromass removal), the total management costs increased with time. However, this cost increase was not proportional between the different methods, being much more pronounced for mechanical control. The findings underscore the pivotal role of early detection, facilitating the implementation of cost-effective mechanical eradication strategies, thereby reducing the reliance on chemical control measures.