Posts Tagged ‘Fruit Bats’

What Measure A1 means for….Bats!

by | September 25th, 2012

Did you know there are more than a 1000 different species of bats? Oakland Zoo has two of the largest species, the Island Flying Fox and the Malaysian Flying Fox. Both are diurnal fruit eating species and as the names suggest, they come from the Islands of Malaysia and Indonesia. Caring for species from all over the world means that many of them are not adapted to our Bay Area weather, so days that feel warm to us, may feel chilly to tropical or desert animals. Days that are cold for us, may feel warm to arctic or high altitude animals.

Flying Foxes are no different; their bodies are adapted to warm, humid, tropical weather. They find our summers pleasant, but winters are just a touch too cold for them! To combat this problem, zookeepers maintain large night quarters which are kept at a constant 75 degrees. This way, our bats are kept warm and comfortable no matter what the Bay Area brings us. However, bats also love sunshine (who doesn’t!) and spend a great deal of their daylight hours outside basking during the summer. In the winter, they are frequently unable to go outside even on sunny days due to the cold temperatures. If Measure A1 passes, the zoo will be able to provide outdoor heating sources for the bats in the winter, so they can bask in the sunlight and stay toasty warm no matter how cold it is outside. The zoo will be able to provide the best of both worlds and maintain a high standard of care and welfare.

Please consider voting “Yes” on Measure A1 on November 6th.

Stuffed Animals in the Bat Exhibit, Why?

by | September 14th, 2012

An Island Flying Fox interacting with a stuffed bear.

An Island Flying Fox with a stuffed bear.

One question we are asked frequently is “why do the bats have stuffed animals?” I would love to just say they are toys for the animals to play with (and often do when I am talking to small children), but the truth is that it is just more complicated than that.
First, I need to give you some background. There has been a lot of buzz in the media lately about the way zoos pair up animals for breeding. Many people are now aware that it is not done by chance and that we breed specifically to enhance and maintain as much genetic diversity as possible. What that means is that some animals are going to get more opportunities to breed than others, simply because of how heavily their families are represented within the captive population. The result is many animals are not recommended to breed and therefore have to be prevented from breeding by some method. The bats at the Oakland Zoo are on loan to us from Lubee Bat Conservancy where the majority of the fruit bat breeding happens in the US. Most of our bats have well represented genes in the captive population. The result is that Lubee gave us ALL male bats. That’s right; all 28 bats in our exhibit are boys, no babies here!
The second thing you need to understand is the concept of enrichment. AZA accredited zoos like the Oakland Zoo strive to provide animals with the optimal care and welfare. This means not only excellent medical care and nutritious food, but also enriched environments that allow animals to perform behaviors that they would naturally perform if they were living in the wild. This can take the form of large naturalistic exhibits like our sun bear or elephant exhibits, or it can take the form of a 50 foot tall enclosure that allows space for the large bats to fly. Sometimes it includes objects that may not be found in the wild, but still provide an opportunity for the animals to perform natural behaviors. This type of enrichment is most frequently seen with our primates. For example, in the wild, chimps will use twigs to collect termites from inside rotting logs. At the zoo, we will give the chimps other types of toys such as PVC tubes or Kongs with treats inside and they must use the twigs to retrieve them. Natural behavior from an unnatural object still results in increased welfare.
So now that we understand these two concepts, we put them together. Mostly our all male colony of bats works well, but for a few months out of each year, they go into breeding season and that causes some discord and a few disagreements in the group. Boys will be boys, right? They feel a need to chase each other out of territories, scent mark and generally just be cranky with each other. We discovered pretty quickly that the number of injuries in our bat colony increased each fall, coinciding with breeding season. While none of the injuries were serious, we still felt that we could improve their welfare if we reduced the number of injuries.
Enter the teddy bear! We hoped (and thankfully were right) that hanging stuffed animals in the exhibit would allow the bats the opportunity to take out their frustrations on something besides each other. Success! In fact, the concept was so successful (a 90% reduction in injuries) that keepers presented their findings at the 2010 Animal Behavior Management Alliance conference – winning an award for their efforts as well as becoming a cover article for their newsletter! The article has also been published in The Shape of Enrichment, an internationally known zoo trade publication focusing on enrichment for animals of all species.
Hanging stuffed animals in the bat exhibit allows our bats to perform the natural territorial behavior spurred by their hormones while preventing injuries within the colony. Natural behavior AND increased welfare from a simple child’s toy. While they may not look like a natural part of the exhibit, stuffed animals are an important component of the care we provide to our bats. Look around the zoo next time you visit and you may notice other exhibits with unusual enrichment items and now you know they serve some purpose that enhances the animals’ well-being.

Watching the Fruit Bats Take Flight

by | August 4th, 2011

Kahuna mid flight

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

Kahuna coming around the bend

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.

Beethoven the bat gets into position

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

Bat landing

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.