Greece has a long history of goat grazing and stonewall building. As such, it provides an ideal setting for my studies on the effects of human land use on ecological communities. The Aegean Sea, to the south and east of Athens, is dotted with hundreds of islands, each with their own land use history and portfolio of plants and animals; these islands are my laboratory for comparative studies on the effects of wall building on local flora and fauna.
In the Cyclades, my “home base” cluster of islands between Crete and mainland Greece, it is rare to see a stonewall without a lizard perched atop. Because most are built without concrete or other sealants, these walls are lizard havens, with mazes of halls and balconies perfect for escaping predators including snakes, cats, and birds of prey, or warming up in the sun. The most common lizard, and the one I’m focusing my research on, is suitably named the Aegean wall lizard, Podarcis erhardii.
This past summer I addressed these questions in two ways, testing for differences in a suite of lizard traits between islands with different ecological settings, and also testing for differences in lizards on the same island with differences in human land use. My preliminary results suggest that lizards on walls differ in behavior, morphology and performance from lizards in settings without walls. Next summer, I am designing a multi-island manipulation experiment that will involve building walls and introducing lizards to eight small islets in order to test whether these lizard trait changes are directly attributable to the stone walls, and whether these changes have cascading effects on the insects and plants of the community, as theory predicts.
I spent my summer in Naxos, the largest island in the Cyclades. Naxos’ most famous feature is its ancient temple of Apollo. From Naxos, I took ferries and small fishing boats to 25 nearby islands in the Cyclades ranging in size from a football field to many miles in length; some were inhabited with fishing villages and others are wonderfully remote and human-free.
There is much still to learn about the roles humans play in the ecological dynamics of the Greek islands. I look forward to continue exploring this beautiful, diverse, exciting landscape.