An important aspect of any keeper’s job is to make sure that their animals are mentally and physically stimulated every day. But how exactly does allowing a bear to become blue, red, yellow, or green help to keep their mind and body keen? Oddly enough, this type of enrichment is not only for the bears but also for young humans. Children that participate in some of the Zoo’s after-school and summer programs get the opportunity to paint burlap sacks different colors with nontoxic paint. After the keepers place these in the enclosure, the bears get to have fun rolling around in the paint and the kids get to watch the big white bears change color. Another type of enrichment, one that I got to participate in, is the preparation of food for the polar bears. By hiding food and covering it with different scents, keepers help keep the bear’s ultra-sensitive olfactory senses in tiptop shape. The keepers believe in giving the bears choices: a variety of foods to eat, different places to sleep and play, and various toys to enjoy. It is better for the bears to be able to entertain themselves, rather than depend on the keepers to supply activities.

A keeper’s job is not, however, all fun and games. They must also do quite a bit of data collection and charting of any changes in eating habits, weight fluctuations, or abnormal behavior. It is important for a keeper to watch for all of these things, particularly when new things are added or things are changed inside of the enclosure. By watching the bear’s reaction to these alterations, keepers can catch undesired habits the bears have and help them stop before the situation progresses. Because animal happiness and well being is a huge part of the Zoo’s goal, reprimanding and negative actions are never taken against the bears. In order to combat undesired behavior, keepers merely ignore the bear until the behavior stops and then immediately give positive reinforcement when good behavior is exhibited.

Gaylene Thomas, team area lead, taught us all a new skill: how to rake deer poop. Yes, I know it sounds odd that she “taught” us how to rake and shovel the poop, but as peculiar as it may seem, there is some technique required. Cleaning the enclosure, however, is not simply done to pick up poop. In order to know how much food is being eaten, keepers must monitor the feeding troughs of the deer. In order to know if an animal has a disease it is necessary to analyze the animals’ droppings. It is not so much the cleaning of the enclosure that is important, but the observations made when animals move in and out of the back holding area. When the animals are moved from one area to another they can be counted, individually identified (by ear notches), and checked briefly for abnormalities in the outward behavior, such as a limp, that cannot be caught while they are bunched together on exhibit.

Both Ms. Thomas and Ms. Murphy have always loved animals and dreamed of a job working at the Zoo. Ms. Thomas took a veterinary technician course at Mesa College and worked at a pet store in order to get hands-on experience with animals. About 18 years ago, she began working at the Zoo as a keeper and, within the last ten years, was promoted to team area lead at Polar Bear Plunge. She now supervises all workers in that section. Ms. Murphy joined the Zoo 13 years ago, after going to Moorpark College. Moorpark is a community college with a special program in which students learn through hands-on interactions with animals at their own on-campus zoo. After starting at the Sun Bear Forest area of the Zoo, moving to pandas, and finally ending with hoofed stock, Ms. Murphy was asked to join the keepers at Polar Bear Plunge. Ever since, she has enjoyed working with the interesting, beautiful, and intelligent bears.

Contributed by Lindsey - Zoo InternQuest Careers Team

The cows, like all hoof ed stock at the Zoo, have special ear notches enabling keepers to keep track of and identify every animal individually. That way, if an animal needs special attention, keepers like Gaylene Thomas, team area lead, are able to recognize and isolate the correct one. The animals are notched the day after they are born when the skin is still soft. Being able to identify individual animals via the ear-notch pattern helps keepers to ensure that mothers are caring for their babies, nursing them and spending sufficient time with them. The locations of the notches on the animals’ ears represent different numbers. One ear is multiples of ten, and the other, numbers between one and nine. With this system, the keepers can make combinations of numbers up to 99. After exceeding that number, ear tags that look like big plastic earrings are used to identify animals.

Across the path in front of the hoofed stock lays one of the Zoo’s main attractions: Polar Bear Plunge. There is much more, however, to the exhibit than what the public can see. I can honestly say that I had never been so close to a polar bear before in my life, being only about two feet from the extremely large, furry bear. This four-year-old sub-adult male, Kalluk, took notice of us as soon as we entered the large carnivore set up of the polar bear exhibit. Because the females at the Zoo are currently in their estrus stages, Kalluk exhibited his pacing behavior, demonstrating his powerful sense of smell and desire to see the females.

In order to ensure the safety of the animals, Polar Bear Plunge has a video monitor, allowing keepers to have 24-hour coverage of the bears. To keep the bears mentally and physically stimulated, keepers use different forms of enrichment. They give the bears various choices, hoping some of them will have positive effects. Keepers have learned that the bears have favorite toys and colors, which exemplifies the intelligence and awareness of their environment exhibited by the bears.

Ms. Thomas, who has worked at the Zoo for the past 18 years, informed us of the importance of introducing new situations and toys slowly to the animals. This is for the safety of both the keepers and the animals. It creates a less stressful environment making things go more smoothly and efficiently.

Along with enrichment, to keep the bears’ experiences upbeat, keepers only use positive reinforcement. This requires a lot of patience, as the keepers have to wait until the bears stop their undesired behavior to reward them. Many methods and tactics have been learned by the keepers from simply watching and reacting to the bears’ behaviors. From their gathered information, keepers are able to develop ways to make “bad” behaviors harder for the bears to do. On exhibit, there is a patch of sticks and logs making Kalluk’s pacing behavior more difficult. As a result, he has to watch and concentrate when he tries to walk there.

Last year, the San Diego Zoo took part in a polar bear reproductive study. In this, they charted vaginal swabs of the females daily to determine when and for how long the bears are in estrus. I was amazed at senior keeper Kelly Murphy’s comment that no restraint or sedation was used to do this. And because of that, I agree with her that the Zoo should be proud of not only the hormonal information that they gathered, but the positive behavior modification techniques they used to safely get it.

Overall, the day was filled with numerous hands-on experiences allowing us to connect with both the polar bears and the hoofed stock. I don’t think I will forget feeding a cloned cow anytime soon.

Contributed by Shelby - Zoo InternQuest Conservation Team

The Zoo InternQuest interns were able to do a gel electrophoresis of California condor DNA with Mrs. Mork. In electrophoresis, there is a plate with agar gel in it. The gel contains little holes called wells where you place DNA fragments. You hook up a positive and negative electrode to each side, with the negative DNA moving towards the positive electrode. The smallest fragments travel fastest, and in this way doing electrophoresis helps to separate pieces of DNA. In our case, we put in the DNA of different baby condors to figure out their sex. Condor sex cannot be determined by a visual inspection, but only by surgery or genetic analysis. Genetic analysis is definitely better for the animal and relatively easy to do.

I was surprised by how much work is done by machines in the lab, especially in analyzing DNA. It makes sense, though, considering that DNA is so small. In order to study genes, they must be extracted from a sample, whether that be hair, blood, or even feces. They use alcohol or another liquid to separate the DNA from all other molecules. We were able to see condor DNA in this stage; it looked a lot like a bunch of strings suspended in liquid. Once that is done, they amplify certain fragments of the genome using polymerase chain reaction (PCR). PCR uses high heat to unwind DNA and uses enzymes to reproduce it. Once that is done, it can be analyzed in the genetic analyzer machine. The machine can be used to sequence base pairs or to find the length in base pairs. It sucks the DNA from a container into a tiny glass tube and through UV light. It analyzes the markers on the DNA and in that way can count the number of base pairs. This is important in determining the species, because you can compare the DNA sequence of the unknown individual against known sequences. This can also help in paternity testing, where you compare a baby’s genes against that of its possible fathers.

Dr. Oliver Ryder, head of the Genetics Division, spoke with the interns about cloning. He stated that the thought process that goes into deciding when to clone is quite complex. Cloning requires the nucleus of one individual and the egg of another. The nucleus of the egg is replaced by the nucleus of the cloned individual, so it takes more than DNA to clone an animal. Unfortunately, to get an intact nucleus you must have a live animal, one that recently died, or preserved cells from the Frozen Zoo®. This rules out cloning extinct animals that are preserved in museums because we don’t have a good egg or intact nucleus. You can’t just clone one hundred of the same animal and save a species, because that would not preserve genetic variety, which is important in preventing genetic disorders. You have to be selective about it. Much to our surprise, cloned animals are not always exactly like the parent either. We saw a slide of CC, a cloned cat, and her nucleus donor side by side and they looked very different. The fur coloring and patterns are based on the inactivation of chromosomes, which occurs during fetal development. The trigger mechanisms are unknown to science. The outcome, however, was a kitten with a very different physical appearance from its donor clone.

Meeting with the Genetics Division staff was inspiring to me. They are very passionate about their research. With all this technology, many times there is still nothing we can do. Many times, we humans are doing too little, too late. I hope that in the future most people can be more proactive about saving species as the Zoo is trying to be today.

Contributed by Erin- Zoo InternQuest Careers Team