The little brown bat native to this region could be extinct by 2030. That’s a possibility mathematician Julie Blackwood and her thesis student, David Stevens ’14, hope to help prevent.
Blackwood, an assistant professor in her first year at Williams, is an applied mathematician whose models help biologists study the spread of infectious diseases. With an ongoing research project on rabies in vampire bats across Latin America, Blackwood is uniquely suited to advise Steven’s thesis on the spread of a disease called white-nose syndrome (WNS) in little brown bats in the Northeast.
WNS was first discovered in a cave near Albany, N.Y., in 2006 and has killed nearly six million bats. For reasons biologists don’t yet understand, a white fungus that grows on the bat’s muzzle seems to trick bats into leaving hibernation early. The bats exit their hibernacula—most often in caves in the Northeast and Canada—before the winter has ended. As a result, they use up their fat stores before food becomes available, and die of starvation.
“Bats are an important reservoir for understanding emerging diseases that are capable of cross-species transmission,” Blackwood explains. “While it’s not known whether WNS is capable of crossing species, it’s important to understand and predict how such highly lethal viruses are maintained within bat populations, and to design and implement effective controls.”
Applied mathematicians partner with engineers, business professionals, or scientists—as in this case—to develop models that help clarify questions involving some unknown element.
“We use data to try to estimate these unknowns, which helps us understand the dynamics and then make predictions based on the findings,” says Blackwood, who earned a PhD from the University of California, Davis, and came to Williams from a postdoctoral position at the University of Michigan.
With the spread of rabies in vampire bats in Latin America, Blackwood says the unknown factor has to do with bats from one colony visiting another colony (possibly infecting one another). It’s impossible to predict what bat will visit which colony when. But the model allows for different possibilities, which can then be tested over time.
Stevens and Blackwood plan to test if such movements among colonies affect the spread of WNS in the little brown bat as well. Then they can replace some of the unknowns with data, and run the simulation again. Stevens is modeling the spread of the disease using information about bat populations.
“Ultimately I will test out different disease prevention strategies,” says Stevens, who wants to continue his research in graduate school. He’s hoping to partner with biologists and environmental scientists to figure out what causes the spread of the fungus before it’s too late for little brown bats.
“The encouragement of collaboration between faculty and students at Williams provides a unique opportunity for undergraduates to be involved in research,” says Blackman. “We are excited about the potential of this work to increase the understanding of WNS transmission dynamics and bat-borne diseases in general.”