FSD 2010 - Corlett

5th International Symposium-Workshop on Frugivores and Seed Dispersal (1985-2010)

Richard T. Corlett

National University of Singapore
Dept. of Biological Sciences
Singapore

dbscrt@nus.edu.sg

Activities

My research for the last 30 years has been largely concerned with the ecology of the deforested tropics. More than a third of the entire humid tropics and more than half of the East Asian tropics have been deforested over the last millennium and the area increases every year. These are the landscapes in which most tropical people live and work, yet we know remarkably little about their ecology. The focus of my research group has been on understanding which wild species survive in these human-dominated landscapes and what factors determine the potential for landscape recovery when human impacts are reduced. For the last eight years I have concentrated on the process of seed dispersal, since it is both a rate-limiting step in forest development and one that is particularly vulnerable to local extinctions of bird and mammal species.

Abstract

Frugivory in tropical forests: what don’t we know and why do we need to know it?

Studies of frugivory in the tropics usually focus on what eats what, but a lot happens before eating starts and basic questions about how fruits are located and selected remain. Some of these questions may appear esoteric, but it seems likely that a more mechanistic understanding of frugivory will be needed if we are to predict and mitigate the dispersal-related impacts of deforestation, fragmentation, logging, invasives, and climate change. What is the role of spatial memory, as opposed to cue-based searching, in foraging on patchy fruit resources? Does any frugivore have a temporal map as well? How important is olfaction in long-range fruit detection, given that odors travel further than light (and sonar) in dense forest? What are the relative roles of vision, olfaction and touch in close-range discrimination between fruits? How important are internal senses―taste and texture before swallowing and a variety of gut sensations afterwards? What feedback on nutritional quality in relation to needs does the frugivore receive after digestion, and how does this influence future choice? How do the answers to all these questions vary within and between the major groups of frugivores? How are the answers influenced by the anthropogenic impacts mentioned above? Gaps in our current knowledge reflect real technical difficulties, but are also influenced by preconceptions (e.g. birds don’t use olfaction) and the very different traditions involved in research on primates, bats, birds, rodents, and other animals.

Some related references

The Ecology of Tropical East Asia by Richard T. Corlett. Oxford University Press (2009).

Tropical Rain Forests: An Ecological and Biogeographical Comparison By Richard B Primack and Richard Corlett. Wiley-Blackwell (2005)