COS 11-1 - CANCELLED - Management and Assessment of the Introduced European Rabbit (Oryctolagus cuniculus) on Island Ecosystems in the Mediterranean

Abstract: The Cycladic Islands (in the Aegean Sea, Greece) are part of the Mediterranean Basin biodiversity hotspot and harbor many endemic species. Plant communities on the smaller islands in this region have largely evolved in the absence of herbivory and frequently lack antiherbivore defenses. This study evaluates the short- and long-term impacts of the European rabbit (Oryctolagus cuniculus), an herbivore that has been released on numerous small islands in the region, by comparing islands that: 1. have historically been rabbit free (ungrazed); 2. are currently grazed by rabbits, and 3. have previously been grazed, but are now rabbit-free. Ecological impacts of rabbits on Aegean Islands were investigated by assessing the abundance, composition, and diversity of plant and arthropod communities. Our results indicate that ungrazed islands have more arthropod species, more specialized or endemic plant species, and less exposed soil. While ungrazed islands did not possess higher plant species richness, they did harbor significantly more small-island endemic taxa relative to presently grazed islands. A non-significant trend in variables collected from post-rabbit islands in comparison to either currently grazed or ungrazed islands suggested that these islands only partially recover after the pressure of grazing is removed. This study indicates that native plant communities in the Mediterranean are not adapted to the presence of this near-native species and that the practice of intentionally releasing rabbits has significant and lasting negative ecological impacts, especially on island endemic plants. We therefore recommend the practice be explicitly banned by government agencies and that rabbit removal projects are initiated to restore critically important small island habitats and protect them from the compounding effects of vegetation loss and climate change.