Modern zoos strive to construct enclosures which both enable and encourage animals to engage in species-specific behaviour, without compromising their visibility to visitors. In 2015, Chester Zoo opened a new development named Islands. Islands aimed to provide a naturalistic and immersive visitor experience by replicating the island habitats of South-East Asia. Many species were transferred from the core zoo to new, custom-built enclosures within Islands throughout the multiyear development. Four of the flagship species for this expansion were the Sumatran orangutan (Pongo abelii), Sulawesi macaque (Macaca nigra), Malayan tapir (Tapirus indicus) and the Malayan sun bear (Helarctos malayanus); all species threatened with extinction in their native habitat and popular with the visiting public. Researchers and students from Chester Zoo’s Behaviour and Welfare Team studied 24 individuals over a total of 33 months (January 2015 through September 2017), collecting detailed behavioural data for 4 separate sub-projects.
These data were organised into 3 conditions: ‘pre-move’ (collected over a 3–7.5 month range) when individuals were housed within the core zoo, immediately prior to their move; ‘early-post’ (the 28 days after transfer to new environments); and ‘post-move’ (collected over a 0.5–4.25 month range) after the initial 28-day period, when individuals were in their new environments. The ‘early-post’ condition was included so that any behavioural changes that occurred during an initial habituation/exploration period would be distinguishable from a longer-term response seen in the ‘post-move’ condition. We used Compositional Data Analysis (CoDA) to examine how the move to a more naturalistic exhibit influenced behaviour. Abnormal behaviour remained low during the study period for all four species, suggesting no adverse responses to the change in environment. Following the move, both the non-human primate species spent more time engaged in positive social interactions with conspecifics, highlighting the importance of social support during enclosure moves followed by an increase in play behaviours indicating positive welfare states. Time spent visible to the public was largely unaffected by the enclosure move for the Sumatran orangutan, whilst the movement to a new environment increased visibility for the Malayan sun bear and decreased for the Sulawesi macaque and Malayan tapir as they explored wider areas available.
This type of large-scale, longitudinal research demonstrates the value of monitoring behaviour throughout the translocation of zoo-housed species and outlines the positive behavioural impacts of providing individuals with naturalistic, species-appropriate environments. This project won Gold in the BIAZA Behaviour & Welfare Awards category in 2022.