The role of animal seed dispersal in accelerating native forest regeneration on degraded tropical lands

This paper reviews the characteristics of animal seed dispersal relevant to tropical forest restoration efforts and discusses their management implications. In many tropical regions seed dispersal by animals is the predominant form of dissemination of propagules and has the potential to facilitate recolonization of native vegetation on degraded sites. The site traits relevant for attracting seed dispersers include the availability of perches, the structural complexity of the vegetation and the presence of food resources, especially fruit, as an attractant. Tree plantations with these traits will be particularly attractive to animal seed dispersers and, therefore, will have higher rates of seed rain than plantations lacking these traits. The efficacy of animal seed dispersal to restoration sites can be limited by the degree of isolation from a seed source, absence of animal seed dispersers in the region and by large seed size. In highly degraded regions, where seed sources may be isolated and animal seed dispersers rare, restoration will require direct seeding or planting. However, even under the best of conditions with a full compliment of animal seed dispersers and a nearby seed source, large-seeded species, because of their relative immobility, should be planted if a full return to primary forest is desired.