July 25, 2018
Hammer-headed Bat Ambassador
- as seen by -Sarah H. Olson
As a charismatic bat ambassador, this male hammer-headed fruit bat’s (Hypsignathus monstrosus) earlier profile shot enthralled readers of this blog and social media alike. There is something about his Yoda-like ears, curvaceous lip folds, and glassy brown eyes that surprise and remind us that we have so much to learn about the world.
What a picture can’t capture are the rhythmic sounds of the males at the lek (recorded by ©Jack Bradbury from The Macaulay Library at the Cornell Lab of Ornithology), a site where they congregate and call to entice females to come and mate. It’s actually a bit like a tree-top swamp of croaking frogs generated by the male’s greatly enlarged larynx and vocal cords as well as distinctive air sacs, cheek pouches, and nasal folds.
We captured him the previous night, having our best netting success when the male bat choir is the loudest. We measured his morphometrics, collected swabs, and blood to analyze later for viruses, and observed him throughout the day for any adverse behavioral response to the customized collar-affixed GPS tracker that weighed less than 5% of his body mass. Moments after this shot, we released him and he methodically took flight using his three foot wingspan to fly into the crepuscular glow.