Thomas H. Kunz



My research largely focuses on how free-ranging mammals acquire and allocate energy and nutrients during reproduction. I am interested in patterns of parental investment and the energetic costs of pregnancy and lactation in temperate and tropical bats. A related area of interest is intraspecific and interspecific variation and energetics of postnatal growth in bats. Specifically, I am interested in determining factors that affect postnatal growth rates, including the quality and quantity of food available to the mother, energy and nutrient quality and quantity of milk output of the mother, and the maternity roost environment. Energy expenditure and allocation are determined using a combination of techniques, including body composition analysis (using extraction methods, calorimetry, and TOBEC), roosting metabolism (using standard respirometry), field metabolic rates and water flux (using doubly-labeled water), and time-activity budgets (using radiotelemetry, video monitoring, and direct observation). In collaboration with Professor Eric Widmaier (Boston University), we are also investigating the role of leptin in the regulation of nightly feeding and seasonal reproduction in free-ranging bats. (Research funded by the National Science Foundation.)

We also study the behavioral ecology of tropical bats. In particular, I am interested in species that modify leaves of epiphytes, palms, and other plants by chewing both primary and secondary veins so that leaves collapse downward, forming so-called "tents." Recently, we have discovered that single males construct tents and recruit females with whom they mate. Tent-making behavior is investigated by capturing and censusing roosting groups, direct observation, radiotelemetry, infrared video recording, and DNA analysis. We are testing alternative hypotheses which may explain the evolution of tent-making behavior, including reciprocity, mutualism, and kin-selection, the effects of social structuring and forest fragmentation on the genetic structure of natural populations. (Research funded by the Center for Ecology and Conservation Biology and the Lubee Foundation, Inc.)

We are trying to assess the ecosystems services of Mexican free-tailed bats (Tadarida brasiliensis), a species that forms one of the largest aggregations of mammals known to mankind. These insectivorous species feed on a wide range of aerial insects, some of which are considered to be major agricultural pests, including corn earworms and cotton boleworms. In collaboration with Professor Cutler Cleveland (Boston University) and Jeff Frank (Indigo Systems Corporation), and Gary McCracken (University of Tennessee), we are using infrared thermal imaging to census bats as they emerge nightly from caves, NEXRAD II Doppler radar to assess landscape patterns of nightly dispersal, and economic modeling to assess the impact that this insectivorous species has on a major agroecosystem in Texas. (Research funded by the National Science Foundation.)

I have also begun research on the phylogeography and population genetic structure of temperate and tropical bats in collaboration with Professor Michael Sorenson (Boston University). We have focused on the big brown bat, Eptesicus fucus, a widely distributed species in North and Central America and two species of Old World fruit bats, Cynopterus sphinx and C. brachyotis. The two latter species are among the most widely distributed species in the Indomalayan region and are subject to a wide range of selection pressures. We are using the mitochondrial genome as well as microsatellite loci to assess both population genetic structure and gene flow in these species. I am collaborating with Professors Christopher Schneider (Boston University) and Michael Sorenson to investigate evolutionary relationships in the Chiroptera using complete sequences of the mitochondrial genome of selected species. (Research funded by the National Science Foundation.)