The study, which focused on bats as an indicator of environmental change, was published Ecology Letters. The researchers said that unless further steps are taken to safeguard and manage the remaining forest, then some species will struggle to survive.
In their research, the authors conducted bat surveys in large forests in addition to forest patches of varying size, in central Peninsular Malaysia. The team measured the numbers of different species present and also assessed the level of genetic diversity within populations of some species.
"We found that smaller forest areas support fewer species, and that those species that remain face an eventual decline, potentially leading to local extinction in the long-term," said Matthew Struebig, lead author of the research, who is jointly based at Queen Mary University of London and the University of Kent.
Research findings
"We found that in order to retain the numbers of bat species seen in pristine forest, forest patches had to be larger than 650 hectares, however to retain comparable levels of genetic diversity, areas needed to be greater than 10,000 hectares," said Struebig.
Co-author Stephen Rossiter, also of Queen Mary, said the findings could have important implications for forest management in the face of the ever-growing demand for oil palm plantations.
"While more species existed in larger forest patches, even small fragments contributed to overall diversity. Therefore, conservation managers should aim to protect existing small fragments, while seeking to join up small forest areas to maximise diversity,” said Rossiter.
Palm production
Palm oil is the most commonly used vegetable oil worldwide, used in processed foods including biscuits, confectionery, margarine, ice cream and as a flavouring agent and texturiser. It is also incorporated into cosmetics and personal care products like soap and lipstick as well as being used for biofuels.
According to the Roundtable on Sustainable Palm Oil (RSPO), it is estimated that about half of the packaged products in supermarkets contain palm oil.
As demand for palm oil has increased, so have concerns about its sustainability. Where palm oil plantation areas have expanded in producing countries this has been at the expense of tropical rainforests, leading to worries about the preservation of the natural environment and the effect of palm oil plantations on local wildlife.
In addition, issues in labour relations and the use of pesticides at plantations have become a concern to many.
As a result, a number of consumer goods companies and retailers have made promises regarding their use of sustainable palm oil; including Unilever which has pledged to use only sustainable palm oil by 2015.