This is the Small Asian Mongoose.
Photo taken by Meiling Tang, thank you!
Often seen by birders out in MaiPo Nature reserve, where they stick their heads out, seemingly not too afraid of the twitchers and photographers.
It is diurnal (comes out during the day), so you have a better chance of seeing it, and not to be mistaken for the Otters that also live in MaiPo.
Usually solitary, but has been known to form social groups and can be seen in pairs or with cubs. it is carnivorous, and also famous for killing venomous snakes, like the Chinese Cobra.