EAZA Best Practice Guidelines for Gorillas EAZA BEST PRACTICE GUIDELINES Great Ape Taxon Advisory Group GORILLA (Gorilla gorilla gorilla) 2017 (2nd Edition) Edited by Mª Teresa Abelló (Barcelona Zoo) Frank Rietkerk (Apenheul) Neil Bemment (Paignton Zoo) EAZA Best Practice Guidelines for Gorillas Editor and Great Ape TAG Chair María Teresa Abelló Zoo de Barcelona, Parc de la Ciutadella sn 08002 Barcelona, T. 34 932256794 [email protected] Editors 2nd Edition Frank Rietkerk, Apenheul, Neil Bemment, Paignton Zoo María Teresa Abelló, Zoo de Barcelona. Contributors María Teresa Abelló Angela Meder Neil Bemment Kirsten Pullen Francis Cabana Sharon Redrobe Andrea Fidget Frank Rietkerk Marianne Holtkötter Neil Spooner Tom de Jongh Hanspeter Steinmetz Werner Kaummans Jan Vermeer Ellen Krebs Istvan Vidakovits Acknowledgements This is the 2nd edition of the husbandry guidelines; firts edition was published in 2006. The present edition involved changing Husbandry Guidelines to Best Practice Guidelines as per EAZA recommendations and some updating of content has also taken place. The authors would like to thank Dr. Christian Schmidt, Dr. Werner Kaumans, and Dr. Ellen Krebsfor their contribution to the 1st edition of the Husbandry Guidelines, the precursor text for this renewed best Practice Guidelines for Gorilla. EAZA Best Practice Guidelines for Gorillas EAZA Best Practice Guidelines disclaimer Copyright (2017) by EAZA Executive Office, Amsterdam. All rights reserved. No part of this publication may be reproduced in hard copy, machine-readable or other forms without advance written permission from the European Association of Zoos and Aquaria (EAZA). Members of the European Association of Zoos and Aquaria (EAZA) may copy this information for their own use as needed. The information contained in these EAZA Best Practice Guidelines has been obtained from numerous sources believed to be reliable. EAZA and the EAZA Great Apes TAG make a diligent effort to provide a complete and accurate representation of the data in its reports, publications, and services. However, EAZA does not guarantee the accuracy, adequacy, or completeness of any information. EAZA disclaims all liability for errors or omissions that may exist and shall not be liable for any incidental, consequential, or other damages (whether resulting from negligence or otherwise) including, without limitation, exemplary damages or lost profits arising out of or in connection with the use of this publication. Because the technical information provided in the EAZA Best Practice Guidelines can easily be misread or misinterpreted unless properly analyzed, EAZA strongly recommends that users of this information consult with the editors in all matters related to data analysis and interpretation. Publication: Published by Barcelona Zoo January 2017 2 EAZA Best Practice Guidelines for Gorillas EAZA Best Practice Guidelines for Gorillas Preamble Right from the very beginning it has been the concern of EAZA and the EEPs to encourage and promote the highest possible standards for husbandry of zoo and aquarium animals. For this reason, quite early on, EAZA developed the “Minimum Standards for the Accommodation and Care of Animals in Zoos and Aquaria”. These standards lay down general principles of animal keeping, to which the members of EAZA feel themselves committed. Above and beyond this, some countries have defined regulatory minimum standards for the keeping of individual species regarding the size and furnishings of enclosures etc., which, according to the opinion of authors, should definitely be fulfilled before allowing such animals to be kept within the area of the jurisdiction of those countries. These minimum standards are intended to determine the borderline of acceptable animal welfare. It is not permitted to fall short of these standards. How difficult it is to determine the standards, however, can be seen in the fact that minimum standards vary from country to country. Above and beyond this, specialists of the EEPs and TAGs have undertaken the considerable task of laying down guidelines for keeping individual animal species. Whilst some aspects of husbandry reported in the guidelines will define minimum standards, in general, these guidelines are not to be understood as minimum requirements; they represent best practice. As such the EAZA Best Practice Guidelines for keeping animals intend rather to describe the desirable design of enclosures and prerequisites for animal keeping that are, according to the present state of knowledge, considered as being optimal for each species. They intend above all to indicate how enclosures should be designed and what conditions should be fulfilled for the optimal care of individual species. EAZA Great Ape Taxon Advisory Group (2017) Chair: María Teresa Abelló, Barcelona – [email protected] Vice-Chair: Jeroen Stevens, Antwerp – [email protected] Gorilla EEP Coordinator: Frank Rietkerk, Apeldoorn – [email protected] Gorilla EEP Vice-Coordinators: Neil Bemment, Paignton – [email protected] María Teresa Abelló 3 EAZA Best Practice Guidelines for Gorillas SUMMARY This document reflects our current knowledge about general biology and keeping requirements to provide adequate levels of wellbeing for Gorillas, the biggest size great ape species, in captive environments. While While providing information about different aspects that should be taken into account when managing gorillas in captivity to ensure a healthy and selfsustainig population, helping to de development of a global “ex situ conservation” program, also provides information about the situation of the species in the wild and “in situ conservation” projects supporting field conservation work in host countries to which all the zoo institutions keeping gorillas are encouraged to support following the IUCN strategy of One Plan Approach. Section 1., Biology and Field Data, reflects our current knowledge of species in the natural environment using the most recent taxonomic information. The philosophy behind this is that ex situ conservation can be used more effectively as a conservation tool if it is part of an integrated approach to species conservation (IUCN, 2014). The potential need for a conservation role of an EAZA ex situ population has therefore been decided in consultation with in situ specialists. This section provides wide and actual information about the species in its natural habitat. Section 2., Management in Zoos, covers housing and exhibition, nutrition, food presentation and enrichment, social structure and behaviour. There is also useful information on the formation of breeding groups and bachelor groups. Control of breeding is an essential component of successful managed programmes and comprehensive information to assist zoo veterinarians to decide on the most appropriate contraception method for their animals is provided. Managed programmes also rely on the movement of animals between zoos and advice on handling and transport is provided. It is essential that gorillas are provided with complex environments and there is detailed practical information on environmental enrichment. One indispensable method of feeding enrichment is the use of browse and information on suitable plants species is provided. A comprehensive veterinary section provides information on current knowledge on all aspects of medical care. Our knowledge can only increase through appropriate research and the final section covers ongoing and recommended research topics. This document is for the gorilla holders to get the better knowledge about keeping this magnificient species in the appropriate and best possible way. Therefore to regularly consult the Guidelines and contact TAG members with any concerns or queries is recommended. 4 EAZA Best Practice Guidelines for Gorillas GORILLA EEP BEST PRACTICE GUIDELINES (Nov. 2015) Table of Contents Acknowledgements and Copyrights Preamble for the EAZA Best Practice Guidelines TAG members list Summary Introduction SECTION 1: BIOLOGY AND FIELD DATA (A. Meder) 1.1. Taxonomy 11 1.2. Morphological features and distinguishing characteristics 11 1.3. Distribution 12 1.4. Population 12 1.5. Habitat and Ecology 13 1.6. Diet 15 1.7. Life history 16 1.8. Reproductive parameters 17 1.9. Social structure 18 1.10. Conservation 20 1.11. References 21 SECTION 2: MANAGEMENT IN ZOOS AND AQUARIUMS 2.1 Accommodation (T. de Jongh, N. Spooner, J. Vermeer, I. Vidakovits) 2.1.1 General remarks 32 2.1.1.1. Climate 2.1.1.2. Sex ratio and enclosure size 2.1.1.3 Providing plans and information for the species coordinator 2.1.2 Indoor accommodation 33 2.1.2.1. Functions 2.1.2.2. Combining the rooms 2.1.2.3. Observation facilities 2.1.2.4. Boundary 2.1.2.5. Floors and substrate 2.1.2.6. Furnishing and Maintenance 2.1.2.6.1 Furnishing 2.1.2.6.2 Maintenance 2.1.2.6.2.1. Doors and service access to the enclosures 2.1.2.6.2.2. Capture and handling facilities 5 EAZA Best Practice Guidelines for Gorillas 2.1.2.7. Environment 2.1.2.7.1. Lighting 2.1.2.7.2. Temperatures 2.1.2.7.3. Ventilation 2.1.2.7.4. Humidity 2.1.3. Outside exhibits 40 2.1.3.1. Enclosure size 2.1.3.2. Boundary 2.1.3.2.1. “U” shaped dry moat 2.1.3.2.2. “V” shaped dry moat 2.1.3.2.3. Wet moat 2.1.3.2.4. Walls 2.1.3.2.5. Glass walls and glass windows built into vertical walls 2.1.3.2.6. Fencing or steel mesh structures 2.1.3.2.6.1 Physical characteristics of the mesh 2.1.3.2.7. Electrical fences and secondary barriers 2.13.2.8. Barriers between the enclosures 2.1.3.2.9 Substrate 2.1.3.2.10.1 Furnishing 2.1.3.2.10.2 Maintenance 2.1.3.2.10.2.1. Exhibit access 2.1.3.2.10.2.2. Outside separation enclosure 2.1.3.3. Environment 2.1.3.3.1. Landscape, topography and vegetation 2.1.3.3.2. Shelter and hiding places 2.1.3.3.3. Water source 2.1.4 Bachelor facilities 49 2.1.5 Mixed species 50 2.1.6 References 51 2.2 Feeding (F.