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Extramural Research

Grantee Research Project Results

Grantee Research Project Results

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)
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.

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The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.

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