Conservation policy in many nature protection areas in Europe is increasingly aiming to develop sustainable grazing managements by introducing large herbivores, particularly in areas where such herbivores have disappeared due to human activities. A new approach of conservation grazing is thus natural grazing, which means grazing by semi-wild large herbivores. In this project, we study the effects of grazing by Konik horses and Highland cattle in the Petite Camargue Alsacienne.