Preference For Individuals Within a Group of Asian Small-Clawed Otters

J. Brink, J.T. Svoke, Carnivore Keeper III

Zoo Atlanta

Georgia , USA

jbrink@zooatlanta.org; jsvoke@zooatlanta.org

At Zoo Atlanta we are currently monitoring the social relationships of our family of 4.5 Asian small-clawed otters (Aonyx cinerea). In late 2004 male “Moe”, born September 1993, was introduced to female “Nava Lee”, born October 2000. Although this was the first time each was paired with the opposite sex, they quickly bonded as a breeding pair, and in 2005 produced two litters of offspring.

As the offspring matured, specific “attachment” type behaviors have been observed and documented within the group. For example, we noticed that the dominant male and one of his sons spend most or all of their time together, and have been observed “holding hands”. In addition, two of the females engage in sexual dominant/submissive behaviors with one another. Noticeable behavioral changes in the otters, when they were separated and with family members, caused us to wonder whether some otters preferred, or were attached to certain other individuals. To see if “otter preference” as we refer to it, existed, the keepers documented how the otters separated during feeding periods, starting in late 2007.

Prior to the onset of the study, the otters were being separated into groups of three during their feedings to eliminate food aggression and to better monitor body weight through hand feeding. Although this behavior initially needed to be shaped, the otters quickly learned that they were brought inside in groups of three for their feedings. Therefore, it became their choice of when they came inside and possibly with whom. Official data collection began on October 21, 2007 , and still continues at this point. Starting July 5, 2008 , groups were ranked as 1, 2 or 3, based on the order that they came off of exhibit. This may show a dominance hierarchy within the group, and could influence an individual’s recorded “preference”, as each otter could only be with two others.

Based on preliminary findings, it appears that some otters show preferences for certain other otters. There is also evidence that some otters prefer separating with the same sex over the opposite sex, while still others are showing no preferences at all. This information could be applied in accessing husbandry needs. In the future, should we need to temporarily or permanently separate the otters, knowing that certain otters prefer to separate with specific individuals may better equip us to help reduce stress levels during those times.