I came across this webpage : http://animalstaiwan.org/diary/?p=22
It is an old blog entry from Sean at Animals Taiwan, a rescue organization there. I have communicated with Sean, the founder, briefly in the past because that is where Sugar the 2-legged dog came from.
The blog entry shows what the situation is like in Taiwan regarding stray pets. Reading the blog entry, you get the impression that stray dogs and cats are falling out of the sky left and right. I don't think the reality is too different.