Tom Barnum

Ph.D. Ecology, 2014

Short Bio:

My research focuses on the consequences of amphibian declines on the structure of an insect-algal Neotropical stream food web in Panama. Using gut content analysis, I am identifying the trophic linkages in a stream before and after amphibian extirpation, then using network analysis to quantify changes in food web structure between pre- and post-amphibian decline food webs. My research is showing that food web structure may be more resilient to species loss than predicted by models that assume static, or fixed, trophic linkages.

I am also examining the lack of compensatory response by the insect community to amphibian declines. Previous research showed an increase in algal-standing stocks following amphibian declines. We predicted that concomitant increases in algal-grazing insects would occur with increased algal-standing stock, but the abundance of algal-grazing insects actually declined after amphibian extirpations. I am using path analysis to examine the potential roles of increased fine sediment accrual and insect gape limitation as potential mechanisms limiting the response of algal-grazing insects to amphibian declines. This research seeks to identify conditional mechanisms for why functional redundancy or complementarity may not occur following species loss.

Honors & Awards:

  •  2013 University of Georgia Travel grant
  • 2013 2nd place Research Presentation, Graduate Student Symposium
  • 2011 Odum School of Ecology small grants
  • 2010 Robert Sheldon Memorial Award
  • 2010 Sigma Xi Grants in Aid of Research
  • 2010 3rd place Research Presentation, Graduate Student Symposium
  • 2009 Odum School of Ecology small grants