The role of fencing in the success of threatened plant species translocation

Abstract

Plant translocation has become a widely used tool to improve the conservation status of threatened plants. Dianthus morisianus (Caryophyllaceae) is a narrow endemic plant which only grows on the Portixeddu coastal dune (South-West Sardinia). Its natural habitat has been strongly modified, and it is currently considered one of the most threatened plants of Sardinia. In a conservation effort, a translocation of reproductive plants was planned. Plants were obtained from seeds collected in the natural population and cultivated at the Botanic Gardens of Cagliari University. The following two suitable areas near the natural population were identified: the first is located in a fenced site which is managed by public administration, and the second is located in an unprotected site. In November 2010, 113 plants were reintroduced in site one, and in February 2011, 25 plants were reintroduced in site two; all plants were regularly monitored. The aim was to analyse the effect of different management activities (i.e. the herbivore and human exclusion) on transplanted plants. The following consistent differences between sites with different management types were found: the survival and growth of D. morisianus were enhanced by reducing herbivory and human disturbance; in particular, fences positively enhanced the plant’s long-term survival, reproductive success and seedling recruitment. This study highlights that management activities (i.e. erection of fences) should be incorporated into translocation design since they contribute to translocation success. Our experience can serve as a model for further translocations of the threatened plants of Sardinia and, more widely, of the Mediterranean islands.