Conflicting Beliefs

https://www.scientificamerican.com/article/buddhist-ceremonial-release-captive-birds-may-harm-wildlife/

A young Vietnamese woman’s husband fell ill. Desperate for a cure, she later recounted, she visited the local Buddhist temple. A monk there instructed her to “release 40 birds, one for every year of your husband’s life.” So she did, purchasing and releasing 40 birds at the temple grounds. The woman soon rejoiced; her husband made a full recovery.

I grew up in a Christian family in Sibu where many people were Christians. I did not know about Fong San, "release a life" until I went to Singapore. An Indian friend's husband, a colleague of my husband, Prof in NTU found a tortoise with red paint written on the underbelly of the tortoise. She did not know what it meant. A friend explained Fong San. She said this is a bad custom, Fong San in this case meant getting the tortoise to carry away the bad luck/sickness to the person who picks it up.
I have found out since other reasons, and in my latest book, I wrote about it.
Thanks Ritchie for writing about it. He uses the term 放生 (Fàngshēng) which is in Mandarin.
Religion aside, some people during weddings and funerals, release doves etc. Environmentally this is frown on.
 A reader commented:

The truth meaning of fangsheng is not releasing bad luck or sickness. It's releasing of a capture animal's life to harvest good karma.

 May be some people in Singapore have other thoughts.

that's their own interpretation. That's loads of bullshit.

There is another bullshit thing they practise. If for no reasons they treat/chia you for a free meal/makan, it is usually a person in that family is very sick. By treating people to dinner/makan, the makan people who help spread the bad luck away. Conversely, a rich properous person has a birthday, people come to eat and even DAPAU/takeaway. The idea is to take the good luck home.

As a writer of both fiction and non fiction,  For fiction, I write for entertainment. Recently, a man bought a tortoise for his pet. His wife asked him if he had checked for any paint. He retorted, of course I had, you think I am stupid.

Buddhists across Asia release wildlife as a show of compassion, but conservationists find that the practice tortures the animals and may impact threatened species.