My research has primarily dealt with the ecology of bird communities, especially the effects of habitat fragmentation on community structure.  While pursuing my Ph.D. at UCLA, I conducted my dissertation research on the breeding bird community in the naturally fragmented forests on the floor of Jackson Hole in Grand Teton National Park, Wyoming.  These fragments occur mostly on old glacial moraines on the valley floor and are surrounded by a sagebrush (Artemesia spp.)-dominated landscape.  The edges of the valley are covered by large tracts of unbroken coniferous forests dominated by lodgepole pine (Pinus contorta).  I studied the distribution patterns in space and time of about 25 species of birds in the fragmented and unfragmented forests over the course of three breeding seasons.  The forest bird community could be divided into four groups of species based on their patterns of distribution in forest patches of various sizes:  1) birds whose incidence is unaffected by patch size, 2) birds which reach their highest rates of incidence in medium-sized (5-80 ha) forest patches, 3) birds which are absent in small patches, moderately common in medium-sized patches, and very common in unfragmented forest, and 4) birds which are only found in unfragmented forest, albeit at low densities.   Incidence patterns were observed to vary in some species whose populations fluctuated over the course of the three years of the study, indicating that some sizes of forest patch were only occupied when population pressure was high and that some birds were forced into sub-optimal habitat.  

In addition to examining bird distribution in relation to forest patch size, I also studied finer-scale habitat selection factors by measuring forest characteristics at the sites where I conducted bird censuses and comparing the distribution of each bird species to the gradients of habitat quality revealed by principal components analysis.  I discovered that forests in smaller patches were much more likely to be monocultural stands of lodgepole pine, while those in larger patches had high levels of spruces and firs.  A number of species were probably rare or absent in the small patches because preferences for the more varied habitat found in unfragmented forests rather than for reasons of area per se.   Some species, however, were habitat generalists which did need larger patches of forest.  I also utilized a nestedness analysis to develop a predictive model of community structure by forest patch size and the minimum patch size requirements of some species.

I am now shifting my research focus to explore more theoretical aspects of habitat fragmentation and landscape ecology.  Within the Laboratory for Landscape and Conservation Ecology at Kansas State University, I am currently working on a project to develop an  Assessment of Extinction Risk in Dynamic Landscapes for Neotropical migratory songbirds, a group of conservation concern.

In addition to the subjects of habitat fragmentation, extinction and conservation, I also have strong interests in paleoecology, urban ecology, and ornithology.  I have assisted with survey work in Wyoming and Tennessee designed to monitor bird population responses to land-management regimes.  I have also conducted or assisted in minor research projects on seabird distribution and on plant community responses to disturbance by fire.  For several years, I assisted in the curation of the bird collection at the Virginia Museum of Natural History at Virginia Tech.

Antelope Flats, Grand Teton

Naturally fragmented forest patches, Jackson Hole, Grand Teton National Park