Blog: When we listen to the zoo, we understand more about our animals (and our people too)

In this week's blog, Dr Paul Rose sums up the ongoing research in the novel study of zoo sound, and where studies need to go next:

Each year, hundreds of millions of people visit zoos worldwide, yet the sonic dimension of these environments is rarely empirically studied. Sound is all around us, influencing our lives positively and negatively. A BBC News article from March 2025 highlights the physiological and psychological challenges humans face from unwanted sounds in cities. The same is true for non-human animals.

Research shows, for instance, that many songbirds alter their vocalisations in louder urban settings compared to quieter rural ones. Sound in zoos clearly matters, not only for animal management and welfare but also concerning visitor experiences and staff wellbeing.

The ESRC-funded Listening to the Zoo Project (LTZP) led by Dr Tom Rice, University of Exeter, explored how sound shapes human and animal experiences, challenging the assumption that zoos are primarily visual spaces. Conducted in collaboration with Bristol and Paignton Zoos, the project investigated how the zoo’s wider acoustic environment influences visitors, staff, animals, and nearby communities. Using interdisciplinary methods from anthropology, sociology, behavioural ecology, and animal welfare science, LTZP developed innovative listening approaches, such as sound walks and silent visits, to explore how acoustic awareness changes perceptions of the zoo. LTZP aimed to promote acoustic mindfulness, encouraging visitors and staff to reflect on how sound affects both human and animal wellbeing. I was fortunate to be part of the LTZP team as a post-doctoral researcher responsible for animal behaviour and welfare elements.

LTZP focused on the sonic characteristics of the sound environment (e.g., tones, rhythms, and variations) to understand how different species experience and respond to sound. This shift fosters a balanced and inclusive approach, recognising sound as a shared, evolving element of zoo life rather than a disturbance to be controlled.

Several papers were generated to galvanise interest in acoustic impacts concerning how animals use their available space, on their behavioural repertoires, and on wider husbandry and welfare considerations. An element of my work in LTZP was to run a workshop to gather the thoughts and experiences of representatives across the BIAZA membership on how sound is and should be considered in important aspects of zoo and aquarium animal management. For example, integrated into enclosure design, or as environmental enrichment, or to be mitigated when large crowds are present. The workshop outputs highlighted important future research questions, notably:

• Sound is an overlooked welfare factor in zoos and aquariums. Recognising and managing everyday acoustic characteristics of enclosures is as essential as providing other optimum environmental parameters.
• Predictability and control over sound are crucial to welfare. Building predictability into husbandry (e.g., use consistent auditory cues before cleaning or feeding), and integrating “quiet zones” or sound-buffered retreats into housing.
• Species and individual differences matter, and some species are not fully considered. Species-specific sensitivities must be noted, and individuals who seem unusually reactive to sound be flagged for welfare monitoring. A bias in research outputs means the sonic needs of some species are poorly understood.
• Sound can be both a risk and a resource. Consider trialling biologically relevant sound enrichment and let animals have control over or an opt in to the experience.
• Zoos need to integrate sound into welfare assessment frameworks. Sound awareness should be a core element of species-specific welfare assessment protocols.

We collected behavioural and spatial data on various species of zoo-housed birds to understand their responses to in-zoo sounds. Birds were chosen based on wild research that documents mixed responses across species to a variable sound environment. Our data showed that even for similar taxa (for example two species of flamingo), the specific environment of the zoo as well as time of day influenced how flamingos responded to sound and to visitor presence.

When assessing the influence of sound across ten bird species, we concluded that quantifying time spent on preening and alert, and recording individual counts of vigilance, as useful behavioural measures of welfare that can help identify disturbances to species-typical behaviour patterns resulting from sounds and/or visitor presence.

Unpicking sound influences from visitor influences should be a focus for any future endeavours, as well as further understanding what constitutes a response to visitors versus a response to sound. We encourage those interested in the interface between the sound environment and animal behaviour and welfare to extend research effort into:  

• How we can adapt and develop methods from more popular sound-focused topics, such as anthropogenic sound impacts on bird behaviour or primate responses to a changed sound environment to questions focussed on overlooked taxa.
• Inactive as well as active behaviours. Aposematic or camouflaged species might still be stressed by an unnatural sound environment, even though they are not moving away from the stimulus.
• How species respond to vibrations and the impact of sound travelling through enclosure furnishings or water. Aquatic species, for example, might be disturbed by life support equipment (e.g., filters and pumps), and we should define how such impacts manifest.
• Build a knowledge base of ecologically relevant sounds and identify which natural acoustic cues support desired behaviours for specific species.
• Increase animal choice and control by improving soundproofing in indoor areas or refuges and managing visitor flow at and around exhibits to create quiet spaces.

Ultimately, our LTZP outputs highlight that there is still much to learn about the impacts of the zoo’s sound environment on animal behaviour and overall quality of life. Additionally, the zoo’s sounds will influence visitor perception of the zoo and its animals, and this should be considered in exhibit planning and design.

Furthering our understanding of the acoustic modalities of the species we house, as well as identifying and deciphering their behavioural responses to external stimuli, will enable us to provide in-zoo housing and care that aligns with their acoustic needs.

- Dr Paul Rose, WWT Slimbridge
Animal Welfare & Ethics Committee (AWEC) coordinator / Research Associate

All blogs reflect the views of their author and are not necessarily a reflection of BIAZA's position