Posted by: Wendy Gardner, Zookeeper
Photos by Wendy Gardner/Woodland Park Zoo
Who weighs nearly 100 pounds, belongs to a family of mammals (Macropodidae) whose name means “big feet,” has a long, muscular tail that helps with balance, turning and support while resting, and cannot walk backwards?
|Harry gets a food reward for cooperating with his treatment.|
That would be Harry, our male wallaroo who lives in the zoo’s Australasia zone. Harry came to Woodland Park Zoo in October 2008 as 2.5-year-old sub-adult, a term we use to describe juveniles that have not yet reached sexual maturity. In December of 2008 he weighed about 62 lb (28 kg), but as of June 2013, the now adult wallaroo weighs just shy of 100 lb (44 kg).
That’s a good weight for him, but that size and strength means we do not want to have to hand catch him if he were to ever need medical attention, both for our own safety and to prevent stress for him. We decided using operant conditioning to get Harry not only used to medical exams but also cooperative in them would be the better alternative whenever possible. Operant conditioning is a type of learning we use at the zoo to encourage behaviors from our animals with the positive reinforcement of a reward.
I've worked with Harry for several years as the Australasia unit keeper and we have built a solid, trusting relationship that has allowed me to do some really great training with him. I started out just doing a simple touch on his shoulders then moved to other areas of his body, always responding to his level of comfort. Leafeater biscuits, apple or yam are used as a reward when he accepts the touch.
|Showing Harry the stethoscope so he knows what is coming. Getting him comfortable is the first step with this training.|
As time went on, I would leave my hand on his body longer and slowly worked my hand onto his chest and could feel his heartbeat—pretty cool feeling, I must say! He did so well with this that I started to use a stethoscope and could then hear and feel his heartbeat more regularly. Being able to hear his heart and learn what is normal for him could help in the future, providing us with a baseline for his health.
|Harry cooperating very nicely with a little stethoscope check.|
Since he did so well with the touch and stethoscope training, I added a new behavior: hand injection. I started by touching his hip, then pulling on the fur and wiping the area with a wet piece of gauze to simulate the use of alcohol that would be used if he were to get a real injection. He did well with all of this so I added touching him with a blunt needle after only a couple of sessions. Again he was offered treats as rewards for allowing me to perform these training sessions with him. If he ever does need a real injection, he’s well prepared for the steps now.
|Harry gets used to the feeling of a blunt needle on his hip. He doesn't seem to mind, preoccupied with snacking.|
An important part of a keeper’s job is learning the behaviors of each individual animal and adjusting our management to what they will tolerate. There are days that he chooses not to do the training and that is fine—it is always his choice.
I am very excited about the progress we have made in a short time and feel confident that all the behaviors he knows and will learn in the future will only improve his care. Thanks, Harry. You are one awesome wallaroo!