Distance and non‐randomness of seed dispersal by the dwarf cassowary Casuarius bennetti

To determine the sources of dispersed seeds I inserted unique tags in fallen Aglaia aff flavida seeds before dwarf cassowaries (Casuanus bennetti) ate the fruits containing the seeds Thirty naturally‐dispersed, marked seeds were re‐located in cassowary droppings m a 400 ha study area The distribution of seed dispersal distances did not differ significantly from a normal distribution with a mean dispersal distance of 388 m, SD= 196 8 Mean distance of dispersed seeds to nearest mature conspecific tree was 170 m, SD= 108 4, dispersed seeds usually landed closer to other conspecifics than their parent The estimated distribution of all seeds (including many undispersed seeds) was leptokurtic, creating high densities near source trees (>0 035 seeds m ‐2 within 100 m of bole) that quickly tapered off (<0 002 seeds m ‐2 > 100 m from the bole), any density dependent effects are liable to be manifest only near parent trees Cassowary movement patterns and resting behavior caused non‐random dispersal of seeds Seeds were preferentially moved to level sites uphill from their source trees along routes that did not cross.steep terrain Undispersed seeds generally landed downhill from source trees This population of Aglaia would probably contract downhill into smaller, fragmented populations m the absence of cassowary‐mediated dispersal