Publication update 21: Project Pteropus press release: Durian Industry May Suffer Without Endangered Fruit Bats

Flying foxes pollinate regionally important fruit crop

Kuala Lumpur, 19 September – Scientists here have discovered that Southeast Asia’s highly popular durian tree is pollinated by locally endangered fruit bats known as flying foxes.

By putting camera traps in durian trees on Tioman Island, Malaysia, researchers collected video evidence showing the island flying fox (Pteropus hypomelanus) pollinating durian flowers, leading to the production of healthy durian fruit. The study has just been published in the journal Ecology and Evolution.

Fig.3
Still shots from a video recording of a flying fox feeding on durian flower nectar.

The spiky tropical durian fruit is highly prized throughout its native region. A ubiquitous icon of Southeast Asian culture, it is also a lucrative industry, generating millions of US dollars in local and international trade. And these economic profits owe a huge debt to bats.

Commonly referred to as flying foxes, large fruit bats of the genus Pteropus are severely threatened by hunting and deforestation. They are often sold and eaten as exotic meat due to an unsubstantiated belief that consuming them can help cure asthma and other respiratory problems.

On top of this, they are also persecuted and killed as agricultural pests, as some people claim that the bats cause damage and economic loss by feeding on cultivated fruits. Consequently, these factors have led to severe declines in flying fox populations worldwide.

Yet these bats actually play very important roles as seed dispersers and pollinators in rainforests, especially on islands. The disappearance of flying foxes could thus have disastrous repercussions for tropical ecosystems. Now, this international team of researchers from Malaysia, France, India, and Thailand, in collaboration with Tree Climbers Malaysia, has found that Southeast Asia’s durian supply could be affected too. Continue reading

Advertisements

Photo update 10: Camera traps and durian trees

Wow, and just like that, we’re already halfway into Year 2 of Project Pteropus! We’ve been quite busy on Tioman, what with faecal sampling and phenology monitoring now taking place on both east and west sides of the island. We also have some very good news to share: the project will be able to keep going for the rest of the year, as the Rufford Foundation have awarded us a small grant – which we are enormously grateful for!

Rufford logo

Meanwhile, it’s high time for another photo update. Back in late April and early May, we put some Reconyx camera traps and Bushnell video traps up in some flowering durian (Durio zibethinus) trees. This will help us study the durian’s pollination ecology better – what animals visit to feed on the flowers, and how each species in this complex network plays a role, and interacts with the others, to influence pollination success and fruit development. It’s also a start in answering the question of whether flying foxes help to pollinate durian trees. This is an extremely complicated bit of research, and we wouldn’t have been able to do it without Dr. Sara Bumrungsri and his PhD student, Tuanjit Sritongchuay (Dr. Bumrungsri’s study discovered that the nectarivorous bat Eonycteris spelaea is a principal pollinator of durian in southern Thailand). They kindly entertained all of Sheema’s questions and requests, and were extremely generous hosts when Sheema visited their lab at Prince of Songkla University – where they taught her more about durian ecology and pollination studies.

Mak Long Hapsah and Pak Long Awang from Kampung Juara have generously allowed us to use their durian orchard for our study. As their trees are already quite old and tall – ranging between 15-25 metres high, we couldn’t climb them ourselves. So we enlisted the services of Saifful Pathil and Muhammad Nur Hafizi Abu Yazid (‘Fizie’ for short!), from Tree Climbers Malaysia. They are professional tree-climbers who are extremely well-trained in safe and effective climbing techniques, using high-quality climbing and safety equipment. So we knew right away that we were in good hands.

We were also joined by Kim McConkey and her sons Sanjay and Ryan, who not only helped us out but were also loads of fun to have around!

So for those of you who have never seen a durian tree, or maybe don’t know what durian flowers look like, or have no idea what professional tree-climbing is all about…here’s a little photo-journal documenting our work in the durian orchard! Also, follow the post all the way down for a little sneak peek of who’s been visiting the durian trees in the night… Continue reading