<p>By Jody Hodges and Michelle Valois<br />
Primate Keepers<br />
Denver Zoological Gardens</p>

<p>Denver, Colorado<br />
(303) 376-4932<br />
mvalois@denverzoo.org</p>

<p>In April of 2003, the Denver Zoological Foundation added a second troop of gorillas as well as another female and silverback male to the existing female pair that currently resided there. One troop would call Denver home, the other would be temporarily housed while their new exhibit was being constructed at The Los Angeles Zoo. This vacationing troop consisted of an adult male, Kelly, and two adult females Rapunzel and Evelyn. While housed at The Denver Zoo, Kelly and Rapunzel had a female offspring, named Tinga, in 2005. In 2007 construction was complete at The Los Angeles Zoo and Kelly and his troop needed to return to California. This paper will focus on the preparations that took place for Kelly, Rapunzel, Tinga and Evelyn to return to California.</p>

<p>In June 2007, the great ape keeper staff, primate supervisor, primate curator, behavior manager and veterinary staff had a meeting to discuss shipment details for these gorillas. We all agreed that we wanted this to be a very smooth process for the gorillas, producing the least amount of stress for them and for us. Without crate training facilities at Denver, a training plan was established to implement separation, hand injection immobilization, pre-shipment exams and crating all in one day. This was a collaborative strategy between Denver and Los Angeles, to eliminate the stress of a second immobilization and crating for the gorillas. We also utilized a drug combination that would ideally provide a smooth and rapid induction state and recovery.</p>

<p>Based on this first planning meeting, our training objective was two-fold. First, we wanted to have all gorillas visually separated from one another, with the exception of Rapunzel and Tinga, who would be separated by a shift door but still in visual contact. This would encourage each gorilla to perform the necessary training behavior without being influenced by others in the troop. Kelly was previously conditioned to be separated on a regular basis from the girls using a creep door overnight. Rapunzel, Evelyn and Tinga were not routinely separated from each other.</p>

<p>Secondly, we wanted all gorillas to accept a hand injection for immobilization. We felt a hand injection, coupled with our chosen drug combination, would produce the least stress for the gorillas during the immobilization.</p>

<p>These four gorillas had previously been trained at The Denver Zoological Foundation to accept a hand injection, and Tinga had received her immunizations using this method in March of 2006. Since this was an already established behavior for Kelly, Evelyn and Tinga, our focus was on using a sharp needle during training, hair pulling at the injection site, and extending the hold time. Rapunzel was our only gorilla that we had to begin teaching the injection behavior. Although she had prior training at Denver to accept a hand injection, she had two immobilizations in 2004, neither of which utilized a hand injection. These experiences created in her a high aversion to syringes and needles.</p> 

[caption id="attachment_569" align="alignnone" width="700" caption="Great Ape Housing at Denver Zoo"]<img src="http://aecetia.net/gws/aazk/wp-content/uploads/floor_plan.gif" alt="Great Ape Housing at Denver Zoo" title="floor_plan" width="700" height="562" class="size-full wp-image-569" />[/caption]

<p>To be able to visually separate all gorillas, we had to use three separate areas in our great ape house. We chose these stations based on where we were able to separate Rapunzel from Tinga in previous training sessions. This arrangement relied heavily on Kelly being willing to transfer away from Rapunzel, which is a behavior that has been difficult for him. After a very short trial run and some resistance from Kelly, we decided to swap Kelly's station for Rapunzel and Tinga's station. We hoped to have more success with these stations as this was where Kelly spent every other night and where he was fairly comfortable. This was a much better arrangement, and put less stress on Kelly, as he was already at his station.</p>

<p>The separation training progressed fairly quickly, and within days we were already closing doors between the gorillas. Evelyn was completely separated into the quarantine yard within two weeks, and Kelly was completely separated into the holding hallway by mid-July. Each gorilla had a training session at each separation, which included maintaining and improving the hand injection behavior, or for Rapunzel, the continued training of this behavior. Multiple times per week, our veterinarian attended and trained each gorilla while separated. We relied heavily on a large pool of trainers to maintain daily separation and injection training. Excellent communication was also needed to ensure we kept moving forward with our behaviors.</p>

<p>With training progressing well, we began to extend the amount of time each gorilla spent separated before having a training session. This would simulate the actual wait times on the immobilization day. We also began to decrease our food reward when asking for the injection behavior, also to simulate the actual conditions on the day of the immobilizations. Since Evelyn would have the longest wait time, we began teaching her a behavior in which she used a paint brush and paints to decorate a canvas. We hoped this would reduce her stress and keep her occupied until her turn. We also had to desensitize Evelyn to her crate being near her outdoor exhibit. We chose to put the crate here to make loading her easy after her exam. She adjusted well to this. We also simulated the increased traffic on the day of the procedure, both foot and vehicular, that would be occurring behind our great ape building and in plain sight of Evelyn. We invited...</p>

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