Promoting wildtype behavioural ecology in sanctuary great apes to aid reintroduction programmes

Great apes are important resident species in tropical forests, having a key role in maintaining humid-forest biodiversity and forest regeneration processes through actions such as seed dispersal and dislodging of dead trees and branches. As Flagship species they also have an inherent value as an essential natural resource from which humans derive considerable biological, economic and societal benefit. Nevertheless, great apes are widely predicted to be extinct across most of their natural range within a generation - creating an ever increasing need for action.

Great ape sanctuaries hold the animals that will be reintroduced back into wild habitats. Forest canopies are highly mechanically complex; consisting of a 3-dimensional array of weight-bearing supports that are flexible, irregular and discontinuous, but captive enclosures tend to be much more homogenous and predictable. Preparing apes for reintroduction is thus a complex and challenging process.

We have created an Enclosure Design Tool (EDT) to elicit wild-type behaviours in zoo apes based on replicating the mechanical behaviour of tropical forest and the physical and mental challenges it poses for wild apes. Our aim now is to develop EDTs for orangutan sanctuaries/ rehabilitation centres in range countries.

A core problem is that the musculo-skeletal system and the brain both respond to the demands placed upon them during development. Strength and cognitive skills are built cumulatively, with key stages for both occurring during pre-adult years and a significant decrease in the ability to build strength/ new skills in adulthood. This studentship will therefore provide a research-base on the capacity of orangutans to learn and carry our natural behaviours across the life course. This will allow us to extend the EDT to sanctuary apes and enhance the success of great ape conservation and reintroduction programmes.

Methodology:
1) Literature review of the behavioural ecology of orangutans. This will include locomotor ecology, cognition, social behaviour and learning and cultural transmission of skills and knowledge.
2) Where behavioural ecology data is missing, undertake focussed field studies of wild and/or captive apes to fill knowledge gaps.
3) Quantify how the behaviour of sanctuary apes differs from wild conspecifics across the life course. Building on observational protocols, this will build a unique, integrated dataset that will be compared to the behavioural diversity and activity budgets of the wild individuals.
4) Use data from 1-3 to implement functional enclosure modifications appropriate for each species.
5) Compare behaviour pre- and post-enclosure modification to evaluate success in modifying behaviour, and develop EDTs specific to sanctuary apes.