Best National Park to see Mammals (in Thailand)

[animalszoos]

What is the best place/national park to see a variety of/guaranteed chance of seeing wild mammals in Thailand?

After looking at Thai National Parks' website, I came across Khao Yai...who had more recorded mammal species than Kaeng Krachan and Kui Buri.

Has anyone visited Thailand and these parks? Which one had a wider variety of mammal species and which one has a more guaranteed chance of seeing mammals?

 

[Jurek7]

Khao Yai has habituated sambar and macaques. Wildlife guides in the area can show you other species like elephants, gibbons, binturongs etc (do NOT use the nonsense night safaris - these are useless). Kaeng Krachan has more diverse species and more chance for truly rare ones like leopard or sun bear. Both places are very good.

 

[Kifaru Bwana]

A third site which is great is Khao Sok. Also good for various primate species, clouded leopard, tapir, sun bear, gaur et cetera.

 

[animalszoos]

Are there any National parks in Thailand which have more open areas/grasslands making wildlife spotting easier?
I know Khao Yai has some grassland sections, but do any others?