Study to save cuscus

THE Admiralty cuscus, is a medium sized (2kg) marsupial native to Manus Island. For thousands of years it has been a part of the diet of Manus Islanders. As a result of unmanaged hunting the animal has been gradually disappearing from some village areas.
Given local concerns over these disappearances the Wildlife Conservation Society undertook a project funded by the Australian Department of Foreign Affairs and Trade to understand traditional management techniques and whether these can be used to help safeguard cuscus populations.
A local clan leader, the late Charles Chuwek of Lehewa, was very interested by the project and invited the Wildlife Conservation Society in to conduct a study within his tambu area believing that his traditional practices could help safeguard cuscus populations.
On Manus Island these tambu areas are opened and closed periodically to allow harvesting of cuscus for important occasions.
John Lamaris, then a University of Papua Guinea student, used the opportunity offered by Charles Chuwek to carry out detailed radio transmitter studies on a total of 13 cuscus in 2013 and 2014 to understand how the animals used forest in, and surrounding the tambu area.
On Feb 20, 2018 the culmination of John Lamaris’s research was published online in the international journal “Pacific Conservation Biology”.
John Lamaris explains, “These tambu areas initially appeared to be a sustainable way to manage cuscus, with typical hunting frequencies and closure periods giving sufficient time for the recovery of the local cuscus population.
However, when we modelled the spatial movements of cuscus we came to a rather different conclusion. What we found was that juvenile cuscus were likely to be wandering out of the tambu area.
As a consequence, when a tambu area is harvested there aren’t going to be enough juveniles nearby to replace the adults lost to harvesting.
As a result mature adults will have to move into the tambu area to allow the population to recover.”
Nathan Whitmore, a researcher with the Wildlife Conservation Society and co-author of the scientific paper is concerned, “What John’s research reveals is that you probably had a very good traditional management system on Manus, however, the effectiveness of that system is reliant on the connectivity of the forest.
If the forest connectivity is broken, for example, by large scale logging or agriculture, then there is no pathway for adult cuscus to move into the tambu area, and the management system will fail.
There is also at least one agriculture scheme planned for Manus that could remove 19–38,000 ha of forest, and if it goes ahead it will have major effects on wildlife.”
John Lamaris adds, “The security of the forests on Manus is a food security issue.
Break the forest and you break the effectiveness of the traditional tambu management system.”