Research

For my doctoral program at Old Dominion University, I am pursuing advanced study in the field of ecology. My independent research project focuses on a number of research questions pertaining to seed dispersal by frugivorous animals. I conduct my field research in the Dominican Republic, where the interactions between tropical wet forest plants and avian frugivores comprise my study system. My project work takes place primarily on several large private cattle farms in the Rio Yaque del Norte Watershed near the town of Jarabacoa in the Cordillera Central. We work in cooperation with several local Dominican partners in an effort to apply the findings of our research to ongoing forest and wildlife conservation efforts.

Jarabacoa Shown in a Larger Map of Hispaniola
 
Landscape Shot of a Typical Cattle Farm


Spatio-temporal Nature of Mutualistic Networks
The network framework for describing and analyzing mutualistic interactions between plant and animal assemblages has played a huge role in contemporary studies seeking to understand the role of mutualisms in structuring communities and maintaining biodiversity. However, much of our current knowledge of these systems is based on data sets compiled from an assortment of field studies with widely varying methodologies. One limitation of  many previous studies is their tendency to consider the composition of communities and their interactions as static objects, largely ignoring the spatial and temporal variability of inherent to natural systems.  One of the goals of my research is to explore how network parameters vary in space and time through continuous year-round monitoring of independent local communities.

Example of a Network Module (subset) From The Study Area

Plant Reproductive Phenology
Seed dispersal by frugivorous animals, while seen in a variety of terrestrial ecosystems throughout the world, plays a critical role in the early life history of plant populations in tropical forests. Where temperate forests have growing periods restricted by extreme seasonal changes in climate, the relatively mild seasonal changes in many tropical forests allow for much more flexible phenological patterns. Rather than having a single annual flowering and fruiting phase, many tropical trees flower and fruit continuously or in multiple annual episodes. Despite these variable phenological patterns, very little is known about how the intensity and frequency of reproduction in plant populations relate to interactions with seed dispersal by frugivores. Using a common tree (Guarea guidonia) in my study area as a focal species, I am investigating how the timing and intensity of ripe fruit availability at individual trees affects selection by frugivores and how this activity is influenced by the local- and landscape-level availability of alternative fruit resources.

Reproductive Phenology Strategies of Tropical Plants

Avian Seed Dispersal in the Assisted Regeneration of Tropical Forests
One of the initial curiosities that inspired my research in agricultural landscapes of the Dominican Republic has been trying to understand the role of birds as seed dispersers in tropical pastures and other deforested areas. What began as a simple experiment to test the differences in seed rain and recruitment below naturally occurring isolated structures has now extended to subsequent experiments for which we are using artificial perches to understand how microhabitat characteristics influence the effectiveness of seed dispersal as well as how these lessons can be applied to ongoing restoration projects in the region.

-2-years-later– 
Seed Dispersal and Regeneration Around Isolated Trees


Artificial Perches in a Small Restoration Plot