A new web-based programme has been created to help zoo keepers encourage chimpanzees to behave more like they would in the wild.
The design tool, developed by University of Birmingham scientists, helps create new features for enclosures that are more like the animals' forest homes and keeps endangered chimpanzees physically and mentally active and interacting socially.
Lead investigator on the study, Dr Susannah Thorpe, said the programme aimed to improve the welfare of the chimps in zoos and give visitors a better idea of how they behave in the wild.
Chimps are endangered and there may come a time when captive-bred apes could be released into the wild to prevent them going extinct, so creating enclosures that stimulate natural behaviour could improve their chances of survival.
Making the enclosures more like their natural habitat, which is complex and unpredictable due to threats from predators and forest growth and decay, also aims to tackle problems for chimps resulting from a more sedentary zoo life, such as obesity and depression.
Keepers observe the behaviour of each animal in their enclosure on a half-hourly basis and input the data into the web programme. The tool automatically compares the information with data on wild chimp behaviour and gives evidence-based guidance on new features zoos could introduce to stimulate natural behaviour.
The researchers worked with Twycross Zoo, Warwickshire, to develop the programme, which saw the introduction of a network of interconnected straps and nets from the bottom to the top of the zoo's chimp enclosure. The network contains the chimps' bedding material and has pockets hanging from it where their food is put.
As the number of chimps and their actions on the network changes, the movement of the straps and nets also shifts, making the environment less predictable and making them arm-hang from straps and duck, dive and bend in different ways.
Dr Thorpe said: "The chimps' habitat in the wild is mechanically very challenging and different every day, so zoos need to be able to recreate a similar environment in captivity.
"We have designed this tool to give zoos the ability to compare the behaviour of their animals to the latest research on wild chimps, and to use that to create physically and cognitively stimulating enclosures that mimic, as closely as possible, the mechanics of forest habitats."
The enclosure design tool will be available to UK zoos through the British and Irish Association of Zoos and Aquariums (Biaza) and the researchers hope it can be developed for other at-risk great apes including orangutans and gorillas.