Zoo Research Guidelines

Studies of the effects of human visitors on zoo animal behaviour

© British and Irish Association of Zoos and Aquariums 2005 All rights reserved. No part of this publication my be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording or any information storage and retrieval system, without permission in writing from the publisher. Mitchell, H. & Hosey, G. (2005) Zoo Research Guidelines: Studies of the effects of human visitors on zoo animal behaviour. BIAZA, London. First published 2005 Published and printed by: BIAZA Zoological Gardens, Regent’s Park, London NW1 4RY, United Kingdom ISSN 1479-5647

Heidi Mitchell1 & Geoff Hosey2 1 Department of Conservation and Wildlife Management, Marwell Preservation Trust, Colden Common, Nr Winchester, SO21 1JH. 2 Department of Psychology & Life Sciences, University of Bolton, Deane Road, Bolton, BL3 5AB.

Acknowledgements: We would like to thank the BIAZA Research Group for instigating the original workshop which stimulated these guidelines. In particular we thank the following members for their valuable comments on various drafts of this document, Dr Stephanie Wehnelt, Dr Amy Plowman, Rob Thomas & Dr Paul Pierce Kelly. We also thank Dr Sheila Pankhurst, Dr Hannah Buchanan-Smith & Alexandra Farrand, whose ideas and comments helped improve these guidelines


The effects of the presence of human visitors on the behaviour of zoo animals are largely unknown; however the presence of people in close proximity is likely to be a significant variable affecting animal behaviour. It should therefore be something that is relevant to anyone interested in undertaking scientific research projects on zoo animal behaviour as it may affect how their results can be interpreted.

Published research which aims to determine the effects of visitors on zoo animals has tended to focus on non-human primates, and there is a pressing need for us to know more about visitor effects on other mammals, birds, and the less charismatic reptiles and fish (for example we are largely ignorant of the effect on reptiles and fish of people tapping on glass-fronted tanks). Furthermore, much has happened in zoos since the first zoo-visitor studies were published in the 1980s. Naturalistic cages, environmental enrichment, free-range exhibits – all of these are a common part of the modern zoo, and it is not at all clear how they affect the animals’ responses to human visitors. For those with more theoretical interests, the detailed analysis of inter-species interactions and communication is itself a current topic, and again one which has largely been unexplored outside of the primates.

Fundamentally, we need to know whether the presence of visitors has any implications for the well-being of zoo animals. This is of utmost importance since many zoos rely on the revenue generated by visitors to provide other aspects of animal care which are key to welfare, for instance, veterinary care and food. Therefore, UK zoos are particularly interested that clear, unambiguous results come from these studies, to inform best practice in maintaining captive animals. These guidelines are designed to offer help in all aspects of visitor effects studies. The information contained here is divided into 6 parts; Initial practicalities, Different types of audience and audience conditions, Animal factors, Enclosure effects, Sampling techniques, References.


1.1 Pilot Study · It is highly recommended that you allow time at the beginning of your research schedule to carry out a pilot study. Heuristic observations will enable you to determine important factors that will influence your study methods, such as: o Typical visitor attendance patterns at the exhibit (quiet and busy times/days)

  • Typical visitor dwell times at the exhibit
  • Types of visitor behaviour that may be important
  • Types of animal behaviour that may be important
  • “Hotspot” areas where high concentrations of animal–visitor interactions take place. You may decide that your study only needs to take account of behaviour at these locations
  • Key individuals in large groups of animals that may be more important to observe than others. This will be dictated by your research question (Be careful that you do not engage in nonrandom selection of study animals unless it is justifiable in the context of your study).

You can also use a pilot study to test your sampling procedures and ensure that they will enable you to effectively measure the variables in question and test your study hypotheses. An important aspect of this will be how often you record visitor behaviour. This will depend on factors such as the number of visitors and location and design of the exhibit (see below, section 5). · A pilot study will also allow the animals to become accustomed to your presence as an observer i.e. will allow for habituation. Although most zoo animals are used to many human observers some may still react to you and this reaction is likely to decrease over time. It is essential that this change occurs before your main data collection begins. It may be useful for you to record some measure of this process.

Example: You may find that the duration and frequency of vigilance in the direction of the observer declines throughout the pilot study, perhaps indicating that the animals are becoming less interested in the observer.

1.2 Tools and Equipment 

  • To carry out a visitor effects study you need to observe both animal and visitor behaviour. This creates practical problems such as how to observe both at the same time. Your university or college may be able to provide equipment to help overcome this problem. Most zoos will not be able to provide such equipment and should not be relied on to do so.
  • A video camera could be used to record either the animals in the enclosure or the public viewing area. However, there may be difficulties in positioning a camera to record the whole area required, ensuring it is safe from animals and visitors and easily accessible to change tapes and battery packs as necessary
  • Another possibility is to have two (or more) observers, one for the visitors and one for the animals. A problem with this technique is the simultaneous timing of events. Both observers must time their observations very accurately in order to later match their observations. It also should be noted that when using the two observer technique, the observers should avoid swapping between the animals and visitors. This would introduce the problem of inter-observer reliability and repeated trials would be needed to determine variation in data collected by the two observers.
  • Other pieces of equipment which may be useful are a decibel recorder to measure visitor noise levels (ideally taken from within the animal enclosure), a clicker to count visitors and a Dictaphone to enable more rapid recording of quickly changing events. However you should consider the limitations of any equipment you use.
  • If your study requires the use of other types of equipment to test a condition e.g. camouflage netting to obscure the view of the visitors to the animals, make sure you have full approval from the zoo to use this equipment in the context you intend.
  • You may find that there are other ways of measuring some variables. For instance, noise levels may correlate well with total visitor numbers. You could also test if the number of visitors at your enclosure correlates reliably with the total number of visitors through the gate. If so you may be able to use daily gate admission numbers (which most zoos record anyway) as your measure of visitor pressure.
  • Visitor self-assessment could be an option you would like to explore. Questionnaires asking for information such as group size, age, clothing, items being carried, time spent at the exhibit, own behaviour and the animals’ behaviour can be handed to the visitors to complete. This may help to reduce your work load during your observation periods. However, you should consider the reliability of this method and check whether it would be acceptable to the zoo at a very early stage of your project. Many zoos may prefer visitors not to be bothered in this way.