Zhuqiaomon is the Bird. (Zhuqiao means 'red sparrow')
Ebonwumon is the Turtle. (His original Japanese name is Xuanwumon, meaning 'black turtle')
Baihumon is the Tiger. (His name means 'white tiger')
Azulongmon is the Dragon. (His original Japanese name is Qinglongmon which means 'blue dragon')
EDIT: Poopydoo! Lon beat me to it!