Imagine getting a shot every morning that gave you all the nutrients you need for the day so that you no longer need to eat.
Would you still have the desire to chew? Would you rummage around the fridge for food anyway? Animal behavior experts think you would.
The desire to forage for food is strong, for us and also for zoo animals. When the ability to hunt for food is taken away, zoo animals act in ways they never would in the wild. Polar bears pace their pens, walruses swim around and around in circles, and giraffes obsessively lick their barn doors. Zoos try to reduce these repetitive activities by experimenting with how zoo animals are fed.
In the wild, walruses spend all day skimming the bottom of the ocean and pounding the ocean floor with their flippers looking for stuff to eat, so researchers at the Indianapolis Zoo have created large feeding mats for zookeepers to stuff with fish and mollusks. Instead of swimming in circles, the walrus spends all day swimming to the bottom of its enclosure to dig its meal out. Another group of walruses were given large balls with fish stuck in the middle. To get to the fish, the walrus has to grasp the ball in its flippers and shake the fish out one by one.
It's easy for us to see these feeding balls and mats as toys for bored animals, but scientists say that encouraging zoo animals to hunt and forage is more than just providing entertainment. Understanding why these behaviors take place is important so we can help animals behave in captivity more like they would in the wild.