What Do Zoo Animals Eat?

Examples of ingredients used for diets at the Binghamton Zoo

Well, that depends. Everyone knows that animals can be herbivores, carnivores, or omnivores, but there are actually many specific feeding strategies. Some animals are frugivores, and eat only fruit, while other are sanguinivores, and only drink blood. Diets for zoo animals are based on research about the natural history of that animal and on detailed records about that animal's weight, coat condition, reproductive success, and fecal composition. However, zoo diet prep is a relatively new discipline.

In the 1940's, one of the major causes of death for captive animals was poor nutrition. In the 1950's, American zoos underwent five major changes that improved quarantine procedures, sanitation, treatment procedures, antibiotics, and feeding techniques. In the 21st century, zoo diets are culminations of research from behaviorists conducting field work, the Association of Zoos and Aquariums' (AZA) nutrition advisory group, vets, curators, and keepers.

Examples of pre-processed grain
for zoo animals

You know the grain that is fed to a horse in a barn or the pellets you feed to your rabbit at home? Zoo animals also eat processed foods. Companies make pelleted food specifically designed for the nutritional requirements of exotic animals. This pelleted food is often much more economical than flying in exotic, perishable foods from all parts of the world on a weekly basis.

Prepared diets (clockwise from top): arctic fox,
mousebirds, rock hyrax, hedgehog, and
fennec fox

Diets must take into consideration the weight, fitness level, metabolic rate, and age of every animal that is being fed. For example, we can't feed an overweight, geriatric wolf a high-fat puppy diet. Additionally, we must consider the morphology of each animal. Lemurs can't eat large chunks of meat; they don't have the teeth to tear the meat or the GI tract to digest it. Red pandas actually have a very sensitive GI tract, so they are only fed bamboo, apples, grapes, and processed leaf-eater biscuits. Additionally, we must consider how to present
the diet. Arboreal animals, like golden lion tamarins, would eat fruit and insects high up in the canopy of South American rainforests. At the zoo, they would starve if we scattered their food on the ground, so we have a hanging food dish in a tree for them. Keepers also have to keep in mind whether the animal sticks its head in the dish to eat or uses a paw to hold the food item. How big should the pieces or biscuits be? Should the diet be in a pan or scattered around the exhibit? Is the animal pregnant or lactating? Will the animal eat all the parts of the food you are giving it? For example, if I don't gut the mice I feed to the owls, I come to work the next day to find guts smeared all over the walls of the exhibit. Finally, animals are as picky as people. Every book, website, and husbandry manual in the world might tell you that Chica, our Andean bear, should like strawberries, but because in reality Chica HATES strawberries, she will never eat them, no matter how hard I try. So I have to find something else that has similar nutritional value that she will actually eat.

Diet sheet for Binghamton Zoo's coatimundi

So, how does all of this work at the Binghamton Zoo? Every animal in the zoo has a diet sheet that lists how
many times a day that animal is fed, what it is fed, how big the pieces should be, what type of pan the diet should be in, and any food items the animal is not allowed to have. For example, the coatimundi is fed twice a day, and gets a different diet in the morning than he does at night. He is not allowed to have grapes in his diet because grapes are the special treat reserved for training sessions with the keepers. If he got grapes in his regular diet, he would be less willing to work for them during training sessions. Additionally, parrots cannot have avocado and canids cannot have grapes or raisins because these foods are toxic to those animals.

Diets are also made up of many parts. We don't just throw bones to the tigers every day and call it done. We have six wallabies at the zoo right now, so they get a very large, four-part diet, to ensure that each individual animal gets enough food.

Four parts of the wallaby diet

The diet consists of shredded kale and romaine, wallaby pellets, leaf-eater biscuits, and mixed produce in chunks large enough that the wallabies can hold the pieces to eat. Diets also have to take into account whether or not the animal is being medicated. Some animals, like Sylvia the mouflon, receive a joint supplement every day. She doesn't mind the taste, so the powder is just sprinkled over her grain each morning. However, some of our animals are much more finicky. Chica, our Andean bear, is quite the prima donna. Right now, she is receiving five pills a day to treat a possible uterine infection, but she hates the taste of her medication. The keepers originally tried hiding her meds in sherbet (one of her favorite treats), but she quickly caught on to that. I know that Chica really

Chica's peanut butter smoothie

likes sugar, so the other day I thought of a different way to hide her meds. This gross-looking picture is actually of a peanut butter, apple juice, honey, and cooked yam smoothie that I made Chica. I crushed her pills and stirred them into the smoothie; she slurped it up without ever knowing there were pills inside! Hopefully we can continue using this smoothie idea until the end of her treatment without her catching on...

Diets are made every day at the Binghamton Zoo, and they are one of the most interesting and sensitive parts of my job. The slightest change to a diet can have a big impact on the well-being of an animal. I constantly have to problem-solve to convince an animal to eat the food or medication I put in front of it. The most common question I'm asked is, "what does this animal eat?" When a little kid or an adult looks at an animal that is very different from a human, food is the easiest thing to relate to!