Natyashastra
तेषां देशानुसारेण कार्यं गतिविचेष्टितम् । पक्षिणां श्वापदानां च पशूनां च द्विजोत्तमाः ॥ १५२॥
Their gait and movements should be performed according to the regions they belong to. So too, O best of Brāhmaṇas, the gait of birds, beasts of prey, and other animals should be represented in accordance with their natural characteristics.
english translation
teSAM dezAnusAreNa kAryaM gativiceSTitam । pakSiNAM zvApadAnAM ca pazUnAM ca dvijottamAH ॥ 152॥
hk transliteration by Sanscript