Seed Dispersal by Toucans in Amazonia, Ecuador

EPA Grant Number: U916250
Title: Seed Dispersal by Toucans in Amazonia, Ecuador
Investigators: Holbrook, Kimberly M.
Institution: University of Missouri - St Louis
EPA Project Officer: Graham, Karen
Project Period: January 1, 2003 through January 1, 2006
Project Amount: $74,710
RFA: STAR Graduate Fellowships (2003) Recipients Lists
Research Category: Academic Fellowships , Fellowship - Terrestrial Ecology and Ecosystems , Ecological Indicators/Assessment/Restoration


The objectives of this research project are to: (1) estimate seed shadows generated by two species of toucans (Pteroglossus pluricinctus and Ramphastos cuvieri) using radio telemetry and seed passage trials, which will generate a probability model of the spatial distribution of seeds based only on toucan dispersal; and (2) estimate seed and seedling shadows of Virola flexuosa using microsatellite markers, which will allow me to create a spatial distribution map of where seeds and seedlings are dispersed. In addition, I will address the following hypotheses: (1) there are species-specific differences in seed dispersal behavior and ecology among toucans (Ramphastidae), and (2) that hunting will impact frugivore densities, movements, and subsequent seed and seedling shadows.


To test these hypotheses, I plan to estimate seed shadows generated by toucans (the frugivore perspective), as well as the actual seed and seedling shadows of V. flexuosa (the plant perspective). Although the genetic-based model includes dispersal by other frugivores, I expect the primary dispersers of V. flexuosa to be toucans; and therefore, my expectation is that these models will be comparable. Ultimately, I will compare toucan-generated seed shadows (from radio telemetry and gut passage rates) with seed and seedling shadows specific to V. flexuosa (using microsatellites).

I will compare seed dispersion between hunted and nonhunted sites to determine if hunting activities are influencing seed dispersal by toucans.

Supplemental Keywords:

fellowship, Pteroglossus pluricinctus, Ramphastos cuvieri, Ramphastidae toucans, seed dispersal, seed and seedling shadows.

Progress and Final Reports:

  • 2003
  • 2004
  • Final