Valmiki Ramayana Ayodhya Kanda Sarga 45 Shloka 31
Original Shlokaनिश्चेष्टाहारसञ्चारा वृक्षैकस्थानविष्ठिताः। पक्षिणोऽपि प्रयाचन्ते सर्वभूतानुकम्पिनम्।।2.45.31।।
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पक्षिणोऽपि even the birds, निश्चेष्टाहारसञ्चाराः without foraging for food and wanderings, वृक्षैकस्थानविष्ठिताः perched on the trees at one place, सर्वभूतानुकम्पिनम् one compassionate to all creatures, प्रयाचन्ते are imploring.
Even the birds instead of foraging for food are sitting motionless on the trees at one place. They are imploring you, you who are compassionate to all creatures, to return to Ayodhya.