Bats of Miagao
SGF conducts annual bat counts for long-term monitoring to provide crucial baseline data for understanding bat populations and developing effective conservation strategies.
Background & History
History of the Bat’s Presence in Miagao
Miagao is a first-class municipality in the Province of Iloilo, composed of 119 barangays and home to 68,115 residents.
Its most iconic landmark is the Santo Tomas de Villanueva Church—built by forced labor between 1787 and 1797. The intricate artistic native motif sculptural relief on its facade earned it UNESCO World Heritage status in 1993. Another spectacular architecture that can be found in Miagao is the Britanico Bridge, formerly Sapa Bridge, near the Sulu Garden Foundation headquarters.
These historic sites draw visitors, but the municipality’s greatest natural spectacle is its thriving fruit bat population. Townspeople report bats coexisting with humans for over 70 years. A 2014 survey estimated 5,000 individuals, swelling to more than 7,000 before they abandoned their former roost in 2018.
The Mystical Bubog
Back then, these bats were roosting on a giant Bubog tree (also called kalumpang/skunk tree) 300 meters from the beach and in the midst of a heavily populated area of town. The locals say the Bubog is considered a centennial tree, but no one seems to know exactly how old they are.
Native to the Middle East, Southeast Asia, and Pacific Islands, Bubog (Sterculia foetida) can reach over 115 feet in height. Coincidentally, the genus Sterculia was named after the Roman god, Sterquilinus—a fitting homage given the bats’ prolific droppings.
This was a drone shot of the Bubog tree back in 2015 and each one of those tiny dots are actually fruit bats. The bats really liked this tree. But where they came from is unknown, why they stayed or chose Miag-ao is even more a mystery.
Bubog trees are considered enchanted in most parts of Panay Island. Perhaps even much more so in Miag-ao. But, the elders would regale at telling stories of enchantment and hauntings that took place in the past. Maybe this is part of the reason why the folks living under and near the Bubog trees leave the bats alone to their own devices, despite the smell and the noise.
One local folklore is that Princess Olayra anchors her golden ship along the creek (perhaps it was a river long ago) beside the Bubog trees before going out to the sea. There were sightings of a white house with bright lights that appeared with Caucasian folks inside inviting out-of-town visitors to come in for dinner. Then later, the white house will vanish into thin air. Or, more recent stories by the people living near the bat trees hearing the sound of an anchor being lifted out of the water in the middle of the night, of abandoned machinery and parts that failed to work beside the Bubog trees and magically lifted in the mist. Folks say that the Bubog trees are home to underworld creatures and one must seek permission first by whispering ‘tabi-tabi po” before coming close or taking anything from the tree. And of course, the classic Manananggal and Aswang lore connected to bats due to their appearance. And there are plenty more of those stories to share.
One certain advantage for the fruit bats—people leave them alone most of the time.
Princess Olayra
Aswang
The Bubog died later on due to structural damage around 2018-2019. No one knows how and why, unsure if it was a typhoon, or what. But parts of the tree collapsed and there is no foliage already. Since then, the bats have moved to other trees but mostly not that far away from the “original” tree.
Annual Bat Count
The annual bat count is the pioneering project of SGF in the community of Miagao prior to its establishment with the aim of establishing baseline estimates of fruit bat abundance and potentially track seasonal and annual fluctuations which would later on provide critical data to prioritize conservation actions. Throughout the years, the SGF collaborates with government agencies such as the Municipal Environment and Natural Resources Office of Miagao and the Community Environment and Natural Resources Office-Guimbal.
Each bat count event involves three key components:
- Direct manual counting of bats in each roost tree, conducted alongside MENRO and CENRO staff.
- Identification and mapping of active roosting trees, using morphological diagnostics.
- Community interviews to capture local knowledge and perceptions about the bats.
Since 2021, SGF has done at least 8 bat counts. The bar graph below shows the summarized result of the fruit bat population for 5 years based on the field work of the Sulu Garden Foundation and its collaborators.
The Flying-Foxes
Locally, bats have been called a lot of names, but some actually say that they would refer to smaller bats as paniki or kabug, whereas the larger fruit bats (flying-foxes) they call ‘kabilaw‘.
Before, it was first thought that the species of fruit bats in Miagao was only the small island flying fox, Pteropus hypomelanus. However, through the PREVENT (Pandemic Response Preparedness for Emerging Bat-Borne Viruses from Rural and Peri-Urban Environments) Program under Dr. Phillip A. Alviola, it was found out that there are different species of fruit bats in Miagao and there are at least three Pteropus species. The previously observed Pteropus hypomelanus, which turned out to be the most abundant hence the assumption, the large flying fox Pteropus vampyrus, and the little golden-mantled flying fox Pteropus pumilus.
From left to right: Pteropus hypomelanus (Photo by: John Paul Nonato, MENRO Miagao, Pteropus vampyrus (Photo by: Daniel Geronimo Panganiban, PREVENT Program), Pteropus pumilus (Photo by: Kim Alunan, SGF).
PREVENT also recorded non-Pteropus species: Jeoffroy’s rousette (Rousettus amplexicaudatus); Common nectar bat (Eonycteris spelaea); Greater musky fruit bat (Ptenochirus jagori); and Peter’s fruit bat (Cynopterus luzoniensis).
Because manual counts cannot reliably distinguish species, SGF focuses on overall abundance. Future plans include refined methodologies—such as acoustic monitoring and genetic barcoding—to parse species-level trends.
Although others remain within town limits, every dusk between 5:30 and 6:30 PM, many bats depart the roost, heading northwest or northeast. The first assumption was the bats are going to Antique more likely to forage and feed.
Yet anecdotal reports note bats emerging near residences up to 750 meters from known roosts. From these areas, fruit trees such as caimito (Chrysophyllum cainito), mango (Mangifera indica), and chico (Manilkara zapota) were confirmed to be some of the feeding trees that these bats visit every night.
In the future, SGF aims to deploy GPS and remote tagging to chart their nightly routes and assess the status of key feeding trees.
Results
March
June
November
January
May
January
May
September
The dates of the survey for 2022 were January 16-18, May 19 and September 29. The SGF staff conducted it together with MENRO-Miag-ao and CENRO-Guimbal.
There were a total of 46 individual trees recorded as the bats’ roosting sites and it consists of twenty (20) species.
The 20 species of trees are: Acacia (Samanea saman), Agoho (Casuarina equisetifolia), Bubog (Sterculia foetida), Caimito (Chrysophyllum cainito), Coconut (Cocos nucifera), Duldol (Ceiba pentandra), Gmelina (Gmelina arborea), Mango (Mangifera indica), Kamansi (Artocarpus camansi), Lanete (Wrightia pubescens), Lunok (Ficus sp.), Mahogany (Swietenia macrophylla), Narra (Pterocarpus indicus), Neem (Azidirachta indica), Payhod, Sambag (Tamarindus indica), Santol (Sandoricum koetjape), Talisay and Tipolo (Artocarpus blancoi). And there was also one Bamboo grass.
The Common Island Flying Foxes’ average total population in the town of Miag-ao for 2022 is four thousand nine hundred seventy-nine (4,979) individuals. The highest average count in a tree was from the Acacia tree with eight hundred fifty-two (852) individuals and the least was from a Neem tree with only seven (7) counts.
Figure 1. the total number of bats per trimester that the count was conducted.
September
News & Blogs
Here are some blogs from our partner organization, Sulu Garden:
- Living in the shadow of the enchanted bubog trees and 7,000+ fruit bats (2015). Read more.
- Bats of Miagao (2015). Read more.
