A comparative study of the effects of introduced mammals on Nothofagus forest at Lake Waiareiti

Comparable sites were examined on Rahui Island, Lake Waikareiti, which is free of introduced mammals, and on the adjacent mainland, which is not. The forest understorey density in Nothofagus fusca, N. menziesii forest has been reduced on the mainland. In the mainland forest there are fewer plants of Pseudopanax and Coprosma spp. and more plants of Dracophyllum pyramidale and Dicksonia lanata. Regeneration of Nothofagus menziesii. Phyllocladus glaucus, and Quintinia acutifolia is greater in the mainland forest and regeneration of Podocarpus spp. and N. fusca is occurring. The vegetation cover below 6 in. is less on the mainland but there is no difference in litter and topsoil depths. Changes in the mainland forest composition are attributed to the effects of the mammals.