Research Interests

 

Currently, I run two main research projects:

(1). Disease ecology of Daphnia

(2). Food web stoichiometry

 

graphic plot
Infected and uninfected Daphnia dentifera with a fungal parasite; from left: infected, uninfected, infected, uninfected

1. Disease Ecology of Daphnia:

We are studying the influence of infectious disease on population dynamics and community interactions. Our work focuses on the determinants of spatial and temporal dynamics of bacterial and fungal epidemics in Daphnia. This work relies on combination of community ecology, physical limnology, and epidemiological modeling. Current projects consider:

  1. “healthy herds”: selective predation keeping the herds healthy (Duffy et al. 2005 L&O, Hall et al. 2005 Am. Nat., Hall et al. 2006 Ecology)
  2. “eating yourself sick and sicker” interactions between hosts, parasites, and resources of hosts (Hall et al. 2007 Eco Letters, Hall et al. ICB)
  3. spatial variability of parasitism among and between lake systems (Hall et al. 2005, Cáceres et al. 2006)
  4. “warmer isn’t necessarily sicker” temperature and physiology as determinants of parasitism (Hall et al. 2005 Ecology)
  5. “friendly competition”: interactions between competitors and hosts via a “dilution effect” (Hall et al. 2009 Ecology)
  6. parasitism as a driver of selection on hosts (Duffy et al. 2008, Duffy and Hall 2008).

Collaborators:

Carla Cáceres (Illinois), Alan Tessier (NSF), Meghan Duffy (Georgia Tech), Marianne Huebner (Michigan State), Sally MacIntyre and Robyn Smyth (UC-Santa Barbara)



 

ovariole
Experimental mesocosms used to test stoichometric food web theory.

2. Food Web Stoichiometry:

We are developing and testing new theory focused around the intersection of ecological stoichiometry and food webs. The stoichiometric approach explores the consequences in mismatches in the elemental composition of grazers and plants. It also considers how supply of resources, especially nutrients and light, can set the stage for these mismatches.Most of our work examines the ability of stoichiometric models to explain:

  1. changes of community composition of both grazers and producers (Hall et al. 2004 Ecology, Hall 2004 Am Nat)
  2. interactions between plant heterogeneity, stoichiometry, and grazers (Hall et al. 2005 Am Nat.)
  3. response of plant stoichiometry to resource supply gradients and grazing (Hall et al. 2005 Ecology, Hall et al. 2007 Ecology)
  4. stoichiometry and trophic cascades (Hall et al. 2007 Oikos)

Collaborators:

Mathew Leibold (Texas-Austin), David Lytle, (Oregon State), and Val Smith (Kansas)