The Effects of Zoo Disturbance on Social Proximity Behaviour in Captive Arabian Rock Hyrax (Procavia capensis jayakari)

Summarised by Sophie Hazeldon from dissertation submitted by Beatrix Cameron.

Take home message:

Zoo disturbances are a potential source of stress for Arabian rock hyraxes. The investigation of hyrax proximity behaviour as a stress response found the number of hyraxes in contact and proximity significantly increased with disturbances in a zoo settling, but their response did not alter between different levels of disturbance.

Introduction:

Studying captive animal welfare is important to develop welfare assessments and improve management strategies. Behavioural expressions of an animal can be interpreted against known natural behaviours, to assess the mental and physical state of a captive animal within a zoo, and is a favourable form of research. Many factors can affect captive animal welfare including environmental change, physical or social behavioural restrictions and potentially human interactions, including visitors to a zoo. Recent research into the ‘visitor effect’ has focused on primates, with a lack of research focusing on smaller, non-primate mammals. Some animals, such as Meerkats (Suricata suricatta) are reported to have no behavioural changes in response to visitor behaviours, whereas quokkas (Setonix brachyurus) are less visible when visitors are present. The Arabian rock hyrax (Procavia capensis jayakari) live throughout Africa and the Arabian Peninsula on rock formations. There is little research into their ecology and behaviour, but evidence suggests their activity levels are dependant on weather, season, location and temperature. It is also suggested that hyrax are not intensely social animals, with huddling behaviours believed to be for protective and physiological purposes, to maintain a constant body temperature and improve predator awareness. As a result of this, it could be assumed that in a captive environment, where temperatures can be better controlled, close contact behaviour is potentially unlikely and frequent proximity of individuals could be considered a defence mechanism, indicating stress of these animals in a captive environment. This study explored whether disturbance in zoos influenced Arabian rock hyrax proximity behaviour and its potential as a stress response.

Materials and Methods

This study was conducted at Drusillas Park, East Sussex, UK. Ten Arabian rock hyrax were used for behavioural studies, including seven females and three males aged between nine months and six years. The hyrax were in an indoor enclosure with a heater and UV lamp that maintained a minimum of 26˚C. Their enclosure was situated near the entrance to the zoo.

Data were observed for six days in December and January 2021/22, eight times a day, for 15 minute periods, chosen at weeks with high visitor numbers. Data were collected using instantaneous recording at two minute intervals, with an initial one minute habituation period, before observations. Observations were recorded 2 m from the glass, and the observer was partially obstructed. An ethogram of different resting behaviours was generated based on previous hyrax studies and organised into three proximity categories: contact, proximity or solitary. The level (high, medium, low, none) and type (visitor number, noise, keeper movement, lighting change) of disturbance were recorded. Observations for each proximity category were collated for analysis and the overall disturbance score of an observation session was calculated as proportionally representative of the impact of each disturbance level. Where data were normally distributed and homogenous, a one-way ANOVA was performed in Genstat. If data were not normally distributed or showed heteroscedasticity, a Krusal-Wallis non-parametric test was conducted. Associations between different times of day and the disturbance score was tested using chi-square.

Results:

The number of hyraxes in contact or proximity significantly increased as disturbance level in the zoo increased, showing a positive correlation. Solitary hyrax numbers decreased with increased disturbance and showed a negative correlation. This suggests that hyraxes are sensitive to zoo disturbances and that proximity behaviours could be an indicator of stress in a captive environment. The number of individuals in contact with one another during high, medium and low levels of disturbance was significantly higher than the number of animals in contact when no disturbance was recorded, but there were no differences in contact between low, medium and high levels. This indicates that hyrax did not alter their response depending on the level of disturbance in a captive environment.

 

This dissertation was submitted by Beatrix Cameron, while studying for their BSc Applied Animal Behaviour and Welfare Degree at Plumpton College, UK. I would like to wish Beatrix the very best of luck and every success with her future career.