As the keeper for the flying fox, one of the most common questions I hear is “when do they fly?” During the warmer months, I can answer that there is usually at least one bat flying from approximately 3:30pm to 4:30pm. If you see one climbing way up high on one of the ‘walls’ of the exhibit, they’re probably getting ready to fly, especially if it’s the wall closest to the Goat Barn. Why do they climb up so high before they fly, you might be wondering. Bats aren’t able to just spring into flight, like birds. Lighter bats just need a little bit of space to drop before their wings can catch them but our big boys need several feet to drop before their wings can catch enough air to get lift and keep their large bodies off the ground. As they get stronger throughout the summer they need less and less room to drop before they fly and they can be seen making shorter flights in the lower areas of the exhibit from time to time.
They also differ from birds in how they land. The legs of bats are backwards compared to other mammals, so their
knees bend towards their backs and the bottoms of their feet face forwards. When they want to land, they fly just above the landing site, like a branch, grabbing it with their feet as they do so and then swinging down into their normal upside-down position. In the case of our exhibit, they usually just fly onto the soft mesh walls of the exhibit, clinging with their thumbnails and toenails.
Many people probably wonder why our fruit bats don’t fly more to get from one place to another and it comes down to their natural history and behavior. In Southeast Asia, where these bats live in the wild, they spend their days roosting in the canopies of trees occasionally waking up to move to a more suitable branch or to change position. In the evenings, near sunset, one by one the entire colony flies from the trees of their day roost in search of food. Once they find trees with tasty flowers and/or fruit, which can be as far away as 30 miles, they separate into smaller family or feeding groups and eat in two hour-long sessions, resting between and after these sessions. When the sun starts coming up, they fly back to their day roosts and noisily squabble for the best positions on the trees where they start the whole cycle over again.
Here at the Oakland Zoo, they don’t have to look hard to find their food. In the mornings, it’s either hanging from clips in their exhibit or, when it’s too cold outside, from chains in their night house and at night we put up 60 bowls full of a healthy and delicious fruit and veggie mixture out for them to eat. Any flying they do is mostly for fun! Right now we
have two Malayan Flying Fox (the larger of the two species that we house here) in particular who are superstar flyers – Kahuna and Beethoven. Most days when the temperature is above 75 degrees F, they can be seen either flying laps around the interior of the exhibit or flying from one side to the other. I got these photos of the bat superstars in action recently.