Migration Ecology

Freetail bat at Frio Cave

Free-tailed bat at Frio Cave

My current research is focused on the behavioral ecology of animal migration. There is amazing diversity in the strategies animals have evolved to handle seasonal disruptions in resources such as food. I’m particularly interested in two very different model systems, bats and moths. Both are very challenging to study, especially during migration. And they are joined in a predator/prey relationship.

Bat migration is similar to its well-studied cousin, bird migration, but there are many important differences. Migration is very common in birds, but seems to be uncommon in bats, perhaps because bats can escape extreme conditions by hibernating, and birds do not. Bats also move shorter distances than birds, but there are a few species that move thousands of kilometers each direction. A larger number of bat species travel in the 100-500 km range, often between hibernacula and summer roosts; these are referred to as “regional” migrants. You can find lots more about bat migration in my book chapter.

Corn Earworms

Corn Earworms

Insects also perform spectacular migrations, but their movement is different from vertebrate migration in some fascinating ways. Many insect species extend each migratory cycle over multiple generations, but not necessarily in both directions. It appears that the migratory moths I study take several generations to move from Mexico to the northern US or Canada in the spring, but the last generation makes the whole return trip. Like birds and probably bats, the moths migrate hundreds of meters above ground at night. That’s where they likely interact, but it is very difficult to study that interaction directly. In my research, I’ve show that over Texas, moth migration in autumn is primarily driven by weather, specifically cold fronts. Bats eat at least 20 different species of migratory moths during that time, and forage more at higher altitudes when the moths are migrating. Those moths likely represent an important food resource as they prepare for their own autumn migration.


Follow me on Twitter

Contact Jennifer:

My photos on Flickr: http://www.flickr.com/photos/batlove/


My San Francisco blog: http://bat-time.blogspot.com

Contact Jennifer via email