LOWLAND GORILLAS AND SEED DISPERSAL - THE IMPORTANCE OF NEST SITES

Lowland gorillas eat the fruit and disperse the seeds of many tree spe cies in the Lope Reserve, Gabon. This study aimed to show whether depo sition of seeds at gorilla ground nest sites conferred any advantage f or germination and seedling establishment as compared to the fate of s eeds deposited in gorilla dung on trails or under parents, Four tree s pecies were chosen for study, which had a range of fruit types and fru iting patterns but which were all important foods for gorillas. Data s howed that gorillas removed significant quantities of seeds from all f our species and deposited them in dung at nest sites or on trail. Nest sites were not always favorable for germination, but the most favorab le sites permitted the best survival and growth of any of the seedling s, including those deposited in dung on trail or scatter-dispersed und er or away from parent canopies. Initial performance in the first few weeks after deposition was not always indicative of long-term survival and growth, so data collection over 1-2 years was absolutely essentia l. The main factors affecting seedling fate at nest sites appeared to be vegetation cover and desiccation. It is suggested that the nesting habits of gorillas are an additional factor encouraging the successful establishment of seedlings over and above the obvious advantages of l arge body size, gut capacity, and extended day ranges. (C) 1998 Wiley- Liss, Inc.