Lately, observing sun bear cubs Pagi and Palu can come with certain challenges associated with their current life stage. Like a growing human child, the sun bear twins have begun asserting themselves with regard to their daily lives (see previous post, Sun Bear Enrichment). We saw this same behavior with previous cubs Danum and Bulan. Mother Marcella has probably gotten used to this, but now their keepers are experiencing a bit of the twins’ “toddler behavior.”
Marcella and the cubs are in the exhibit overnight so as to provide them with the maximum roaming room. Prior to morning observations, the group is shifted off exhibit, and their exhibit is restocked before re-releasing them for my observation period. Often, the little ones are happy to shift off, enjoying a treat reward from their keepers for doing so. But they aren’t always so compliant.
More and more frequently, one or both cubs might refuse to come in. Our female cub, Pagi, is the most frequent culprit. She’ll sit lounging comfortably in her climbing structure, looking about her and generally ignoring the keeper’s calls. Today, both cubs were stubborn and remained on exhibit, engaged in a play bout with each other that apparently could not be interrupted.
When the cubs choose to have it their way, keepers will not reinforce their behavior by restocking the exhibit. Instead, Marcella is fed in the back, and the cubs are left without treats to enjoy when they come down from their climbing structure. Eventually this will teach them that the way to their breakfast is by following keeper commands.
The driving force behind the cubs’ behavior is that they are, in fact, not highly food motivated. They really don’t seem to care if food is left for them or not. This is because they are still nursing and gaining many of their calories from Marcella. Although I don’t actually observe nursing much anymore, the cubs’ lack of interest in solid foods clearly points to their ability to meet their caloric needs in some other fashion.
As they grow, their daily caloric needs will continue to climb, and eventually they will come to miss those breakfasts that they opt out of. Before you know it, they will jump at the chance to come in and get their fill of raisins, yams, apples, or kibble. In the meantime, we will just need to be patient with them. Our twins are demonstrating normal, healthy, developmentally appropriate behavior, a sign to us they are growing up right on schedule!
Suzanne Hall is a senior research technician for the San Diego Zoo’s Institute for Conservation Research.