AbstractsPsychology

Animals in the zoo environment are exposed to a multitude of sounds. Some sounds, such as those from the visiting public, are inexorable components of the sound environment of a zoo and may, in some cases, have a negative impact on the behavior of animals. Auditory masking of visitor noise, such as from waterfall features, may alleviate adverse effects of noise but this has not yet been evaluated. Other sounds, such as music or habitat sounds, may be introduced in an attempt to enrich the animals but their utility is questionable. This project investigated the influence of the sound environment on four species of callitrichine monkeys: pied tamarin, white-fronted marmoset, golden lion tamarin, and callimico. The goal of this research was to identify enriching and adverse sound environments and, in the case of the latter, evaluate strategies to ameliorate this effect and improve welfare. The general hypothesis was that sounds experienced in the zoo setting can affect the welfare of zoo-housed callitrichine monkeys. This project focused on sound from a nearby waterfall feature as well as music and other sounds that may be viewed by some as auditory enrichment. The aims were fourfold. First, hormonal and cognitive methods for assessing welfare were evaluated. Second, the potential of sound from a nearby waterfall feature to provide beneficial auditory masking was assessed. Third, rainforest sounds and music were assessed as potential forms of auditory enrichment. Lastly, the influence of providing access to quiet off-exhibit areas was examined. Experimental manipulations of the waterfall feature did not identify beneficial auditory masking effects and indicated waterfall noise may instead be aversive. Playing rainforest sounds or music did not elicit behavioral benefits. Providing access to off-exhibit areas was beneficial and appeared to ameliorate some stressful effects of the waterfall noise. These results indicate the sound environment did influence the welfare of callitrichine monkeys, albeit minimally, and suggest quieter sound environments may be beneficial for these species. Providing access to quiet areas is an important strategy for promoting environmental choices for zoo animals and opportunities to cope with noise. Advisors/Committee Members: Lukas, Kristen (Advisor).