February 06, 2018

By David Powell
Director of Research
 

Here at the Saint Louis Zoo we are dedicated to the care and well being of our animals and researchers in the Department of Reproductive and Behavioral Sciences are working with animal care staff to study various husbandry practices that can benefit the animals living here and at other zoos. Here are a few of the projects we are working on now.

The Reptile Exercise Project

Reptiles use the environment to adjust their body temperature and metabolism. You probably are aware that some reptiles like to bask in the sun to warm up for a while before going about their daily activities.  Zoos have long provided warm basking spots to reptiles using stationary lighting, artificial “hot rocks”, and other tools.  One limitation of these approaches is that they don’t replicate natural changes in temperature throughout the day. In the wild, as the sun moves, basking spots appear and disappear, encouraging reptiles to move around and explore more of the environment. In the desert exhibit at the Zoo’s Herpetarium, we have installed a dynamic lighting system in which different lights turn on and off throughout the day to replicate the movement of the sun.  Researchers observed the habitat’s inhabitants, gila monsters and chuckwallas, before the new system was installed and after the dynamic lighting schedule had been turned on.  This winter we are reviewing the video footage to see if the animals responded to the lighting change and become more active and used more of their habitat.  If it works, this would represent a great advancement in reptile husbandry that would promote exercise and more natural exploration behavior.  Dynamic lighting systems could be programmed differently for different times of year, providing even more variation in the reptiles’ environment.

What do birds find interesting?

Providing environmental enrichment – new objects, scents, sounds, flavors or other kinds of stimulation – is an established practice in animal care in zoos and aquariums.  Enrichment gives the animals choices of how to spend their time and provides opportunities to use physical and cognitive abilities to solve challenges and obtain rewards. In theory this all sounds great, but some types of activities just aren’t interesting to some kinds of animals.  Just like some humans like to do jigsaw puzzles and others find these uninteresting, not all birds find the same enrichment stimulating In the Zoo’s bird house, we are studying various kinds of enrichment to see what kinds of activities different types of birds find engaging.  We are looking at several bird species:  plush-crested jays, red-crested cardinals, sunbitterns, ringed teal, and bamboo partridges and presenting them with novel objects, food enrichment, sensory stimuli, activity-based enrichments, and combinations of these and recording responses.  Although keepers already do a quick assessment of various enrichment practices, we will be doing our own side-by-side assessment to validate this quick scoring method.  Our study will allow us to watch the birds for longer periods of time to see if the rapid assessment gives us insight into longer lasting effects of environmental enrichment.  These results will help keepers allocate their time and creativity to developing enrichment activities that will be interesting to different kinds of birds.