Department of Biology

Research

Alex Jahn’s research focuses on the ecology of migratory birds, including how and why they migrate, their ability to carry pathogens, and how they can serve as sentinels of rapid environmental change. To do so, he studies birds across several countries, from the USA to Argentina.

American Robin migration:

By studying a common backyard bird in much of North America, the American Robin, Jahn and his colleagues are attempting to decipher its role in spreading zoonotic pathogens, such as Lyme disease and West Nile Virus. These viruses are shared by robins and humans, such that understanding when, where, and how robins migrate across North America can provide important clues about how changes in the environment can affect outcomes, such as zoonotic disease outbreaks among humans.

An interesting feature of American Robin migration is that while some Indiana robins fly south for the winter, other robins remain in the state year-round. In fact, an individual robin may migrate one year and ‘stay put’ the next. This “partial migration” pattern, in which some robins migrate and others don’t, offers new insights into how robins and other birds may be shifting their migratory patterns—and thereby their ability to carry pathogens—as a result of rapid environmental changes in Indiana and elsewhere. To learn more about this project, see: https://eri.iu.edu/research/wildlife/forecasting-infectious-disease-risks.html.

Flamingo ecology and conservation:

Even the most pristine habitats across the planet are facing eminent threats from human-induced, rapid environmental change. A case in point is the high Andes, whose ancient volcanic landscape can at times look like that of another planet. Yet, this seemingly barren place is home to a surprisingly high level of biodiversity, thanks in large part to the presence of saltwater wetlands, which contain a complex food web made up of microscopic phytoplankton, such as copepods and diatoms, to large animals such as ducks, Llamas, and maybe most surprisingly, flamingos. Although most people may not associate the Andes with this brightly colored tropical bird, these mountains are home to not just one, but three species of flamingos (there are six species of flamingos on the planet). In particular, the Puna and Andean Flamingos are highly dependent on high elevation, saltwater wetlands to forage and breed. Unfortunately, many of those wetlands are increasingly threatened by climate change and mining activities. The central Andes are home to some of the largest lithium reserves on the planet, and a need for lithium in rechargeable batteries in a variety of devices, from phones to electric vehicles, is driving much of the mining activity in the wetlands these birds depend upon to breed and survive.

These flamingos regularly move long distances, with some spending the summer in the high Andes above 14,000 feet, then overwintering in wetlands of the Argentinian pampas, close to sea level, where they face additional threats from large-scale agricultural activities. Previous research on flamingos has shown that knowing which wetlands flamingos use at different times of year is critical to developing effective conservation measures to protect them. However, very little is known about which lowland wetlands different populations use during winter, precluding the development of effective conservation plans for this species.

In response to such threats, Jahn and his colleagues in Argentina, Enrique Derlindati, a professor and researcher from the Universidad Nacional de Salta and Joaquín Cereghetti, an Argentinian biologist, attach satellite transmitters to the flamingos, allowing the scientists to better understand which wetlands these birds use at different times of year. With this data, they will make recommendations as to where conservation actions should be targeted for these amazing and increasingly threatened birds.

Midwest Center for Birds and Biodiversity

Alex Jahn is co-director and a founding member of the Midwest Center for Birds and Biodiversity at Indiana University Bloomington.