Seed dispersal in Philippine montane rainforest and successional vegetation: Role of birds, bats, and wind

I characterized the vegetation, fruiting phenology, and means and extent of seed dispersal in montane rainforest and associated successional vegetation on Mt. Kitanglad, Mindanao, Philippines, in order to determine the potential of vertebrate and wind-dispersed seeds in forest regeneration.; Seed rain was sampled over one year with 46 pairs of seed traps, each 1 m2 in area, placed in forest and in the successional area up to 40 m from the forest edge. One trap in each pair was open during the day, when birds are active; the other was open at the night, when bats forage. For vertebrate-dispersed seeds, annual seed rain density (seeds/m2 ) was 1195 ± 161 in the forest and 9510 ± 4045 in the adjacent successional area. In both habitats over 80% of all vertebrate-dispersed seeds came from plants of that habitat. Input of forest seeds into the successional area declined with distance from the forest, with day traps collecting more seeds than night traps. At 40 m from forest, annual seed input was only 6.5 seeds/m2 in the day and 1.1 seeds/m2 in the night. Annual input (seeds/m2) of wind-dispersed seeds from forest trees was 1739 ± 354 in the forest and 1405 ± 531 in the successional area. Input of wind-dispersed seeds of forest trees into the successional area declined with distance from forest, but seed input at 40 m was still appreciable at 102 seeds/m2/year. Apart from wind-dispersed seeds, those of Ficus and of climbers/vines were abundant in the forest seed rain although source plants were not particularly common. The overall seed densities documented in this study are the highest reported for tropical forests, probably because small seeds, which dominated the seed rain, were effectively sampled.; Many factors, biological and social, affect forest regeneration on degraded land. As seed input from vertebrate dispersers declines markedly at short distances from forest, management efforts aimed at increasing movement of frugivores out of the forest will be needed, such as planting trees that produce fruit. Wind-dispersed pioneer trees may be effective in the colonization of degraded sites because they appear less limited by seed input, but manipulations to enhance establishment will be necessary.