IC Broadcasting’s Island Symbiosis – Listening to Taiwan: How Are You Doing After Being Released Into the Wild, Dear Pangolin?

In recent years, many instances of injured pangolins have been recorded throughout Taiwan. After being found, these injured pangolins are sent to wildlife rescue centers for treatment and care. If they recover and are healthy enough, they can be released back into the forests. But have you ever wondered how those pangolins are doing after being released in the wild?

In this episode, we go to the mountainous region of Chihshang Township in Taitung County. We will follow Sun, Ching-Min, a post-doctoral researcher from the Department of Entomology at National Chung Hsing University, and Lin, Yu-Hsuan, a veterinarian from the WildOne Conservation Association, to track down a pangolin released in the wild last October and find out if it can continue to live in the wild after being released.

Tracing the pangolin released last October

Dr. Sun, Ching-Min pointed out that the pangolin we are tracking is a male who was attacked and bitten by stray dogs in September last year. He was sent to WildOne for treatment and released in October. He weighed about three kilograms at the time he was wounded and was presumed to have been born in the winter of 2020.

“He is a lucky one. He was spotted by bird-watchers who chased the dogs away.” Veterinarian Lin, Yu-Hsuan said. This pangolin was rushed to WildOne, and the examination revealed multiple puncture wounds and lacerations on its tail and hind legs, with many scales that have peeled off. X-rays confirmed that the injuries on its hind legs were flesh wounds with a good chance of healing, but the tail had been fractured and needed to be amputated. She said, “about 5 centimeters needed to be amputated.”

Fortunately, this pangolin recovered well from the tail amputation and was deemed healthy enough for release after staying only a month or so in WildOne. Before release, Dr. Sun, Ching-Min installed a radio transmitter used for radio-tracking that constantly sends out radio signals onto the pangolin’s tail scales.

Using radio tracking to catch up

Dr. Sun, Ching-Min holds the antenna of the radio receiver up in one hand and the receiver in the other. He places the receiver close to his ear and listens carefully to the beeping signal.

"Radio-tracking works just like a radio walkie-talkie." Dr. Sun, Ching-Min explained. Just as two radios have to be set to the same frequency before they can talk to each other, a radio receiver can be set to the frequency of the transmitter on an animal to receive its signal. After receiving the signal, the receiver will convert it to a beeping sound. The researcher can use the volume of the beeping to determine the proximity of the animal and then triangulate its location.

We followed Dr. Sun, Ching-Min, as he moved along the narrow industrial path. Dr. Sun, Ching-Min listened intently to the beeping sound, turning the direction of the antenna from time to time, sometimes even turning the antenna 180° and back again to determine the difference in sound. It took about ten minutes to locate an individual pangolin, which was not far inside a copse of bamboo trees on the mountain wall in front of us. "This is a newly found burrow.”

Suddenly, the original frequency of the beeping became faster. Dr. Sun, Ching-Min explained that this means that the animal moved. Because pangolins usually hide inside a burrow to sleep during the day, we think this one may have turned over or moved its body inside the burrow.

Assess the effectiveness of rescue and wildlife release through tracking

Why do we track pangolins that were released back into the wild? Dr. Sun, Ching-Min said that the purpose of tracking is to understand whether the treatment method and the release site are suitable for this individual animal. “The correlation between the release site we choose and the survival rate of pangolin can only be seen through long-term tracking and monitoring. If we selected a site that wasn’t suitable, we will choose another location next time we release an animal.”

Veterinarian Lin, Yu-Hsuan explained this from the treatment point of view, saying, “One of the bigger problems in making medical decisions now is that we do not know what degree of amputation will cause an animal to be unable to survive in the wild.” She said the tail is essential for the pangolin to survive in the wild. They use their tails as auxiliary prosthetics for climbing trees and eating ants. Pangolin mothers also put their babies on their tails. Therefore, survival in the wild will be extremely challenging if they do not have their tails. It is now generally believed that pangolins with half to two-thirds of their tails amputated are probably not suitable for release into the wild. However, we lack empirical data in the field to support such a claim, which is why WildOne is collaborating with Dr. Sun, Ching-Min to track and follow up on the released pangolins.

The tracking work includes radio positioning every two days to obtain its location and determine whether the tail amputation will affect its activity range. At least once a month, an automatic camera is set up outside its burrow to confirm its health status with photos. The pangolins are recaptured every quarter and brought back to the rescue center for health checks. Veterinarian Lin, Yu-Hsuan pointed out that this individual was recaptured in mid-December last year and did not lose too much weight at the time. The blood tests and the healing of the tail fracture were quite good, so he was assessed to be doing well after being released.

Exploring the old burrow

In addition to radio positioning, today, we have to adjust the location of the automatic camera set up and move to the new burrow we had just found to investigate. So we followed Dr. Sun, Ching-Min and the veterinarian in the opposite direction, through the trees and bamboo, and arrived at another burrow next to some bushes. Next, the vet took down the automatic camera next to the hole.

"The pangolin burrows we see when hiking and mountaineering are usually not burrows for dwelling, but those for foraging." Dr. Sun, Ching-Min pointed out that the burrows dug by pangolins can be divided into two types: dwelling burrows and foraging burrows. A burrow will only have one of these functions. A dwelling burrow is used by pangolins for sleeping and will be in a more secluded place, sometimes up to 5 to 6 meters deep. The foraging burrow is only about 1 to 3 meters deep. The pangolin will dig a hole towards the food where there is something to eat.

If you look closely, you can see that the weeds and leaves around the entrance of this burrow are piled up and pulled inside the cave, which is the work of the pangolin. Dr. Sun, Ching-Min explained that because pangolins have very little hair on their bodies, to avoid the cold, they will "pull grass" in winter, that is, collect dead branches, fallen leaves, and grass and pull them to the entrance of the burrow to keep warm, and even pull them into the cave to make a nest.

Today, let’s follow Dr. Sun, Ching-Min and Veterinarian Lin, Yu-Hsuan, to care about the life of the pangolin after its release into the wild.