Distribution and reproductive capacity of Deschampsia antarctica and Colobanthus quitensis on Byers Peninsula, Livingston Island, South Shetland Islands, Antarctica

The Maritime Antarctic is one of the regions where regional climate change is most intense and the reproductive performance of plants may be enhanced. Reporting the distribution of Deschampsia antarctica and Colobanthus quitensis on Byers Peninsula (Livingston Island, South Shetland Islands), our results confirm that D. antarctica is more widespread than C. quitensis. Flower and seed development of both species varied between sites. Deschampsia antarctica produced more viable seeds than C. quitensis, although fully developed seeds were not found at all locations. Seed production in C. quitensis was low in comparison with other Antarctic locations. The largest cushions of Colobanthus observed in 2002 were 15cm in diameter, suggesting that the populations may have established at least 50 years ago. Deschampsia antarctica tussocks were very often 20 cm in diameter, although turf areas up to 1.5m across were also observed, probably due to coalesced aggregates of individuals. This study shows that, although seed production is low, the presence of seedlings and young individuals suggests an expansion process.