I have two main field work efforts right now. First, as summarized under Collaborative Projects, Bill Morris and I continue our long term study of the demography of range limits, a study of two circumboreal tundra plants. We initiated the current multi-site study in 2001, and worked on the demography of one of the species, Silene acualis, as far back as 1995. The main questions of this work are:
This work is generously supported by NSF’s Long Term Research in Environmental Biology program.
Second, I work with several other researchers on the community ecology of savannas, and in particular how termites shape the functioning of ‘black cotton soil’ savannas in central Kenya. Past work in this system has focused on what individual termite mounds do to plant and animal communities, as well as nitrogen dynamics, and also how these effects and the over-dispersion of termite mounds create spatial patterning in these communities (see Publications for some of the results of this work). Collaborators on this work include Allison Brody, Todd Palmer, Kena Fox-Dobbs, and Rob Pringle. I have also worked on side projects in this same study system that include collaborations with Todd Palmer, Jake Goheen, and Janet McLean. Rob Pringle, Corina Tarnita, and I have just received NSF support to continue this work, with a sharper focus on the ways that spatial structure alter community dynamics.
Another current field project involves the ecology of pocket gophers in montane and subalpine systems and also their geomorphic effects. This work is collaborative with two lab members (Lizzie Lombardi and Ryan Langendorf) and also two CU Boulder geomorphologists, Bob Anderson and Eric Winchell. First, we are interested in the ways that gophers and conifer trees interact, with the hypothesis that mutually negative effects between trees and gophers are important forces in the creation of the mosaics of sharply delineated forest and meadow that are typical of many mountain landscapes across the West. Second, we are interested in how gophers shape geomorphological processes, and how we can use a better understanding of gopher ecology to inform geomorphological models.
Finally, I have recent or on-going side projects that involve field work on lichens, rare plants, and other systems.
I am also involved in multiple other projects that do not involve field work. The majority of these involve population ecology, often in the context of conservation questions. These are all collaborative and include recent projects on: California condors and the effects of lead exposure, interpretation of recent trends in data on Yellowstone grizzly bears, the extinction of the Steller sea cow, and the importance of small scale habitat variation on a sensitive lichen in Spain. I also work on various more synthetic questions, as can be seen in my list of publications elsewhere on the website.