The dolphins stay in the Garjontola pool until midmorning the next day and then vanish. Piya tries to ask Fokir where the dolphins go when they leave, and he eagerly starts to follow them. He points out crocodiles, and then Tutul points to where the dolphins are catching fish. She remembers watching dolphins fish on the Irrawaddy River, though then, they'd actually fished with the fishermen accompanying Piya. She'd been shocked to see the symbiosis between the dolphins and the humans.
The dolphins here show that it's not just a fantasy for the Sundarbans residents to feel connected to the land: in this case, the fishermen have a very close relationship with the dolphins that benefits both parties. This offers an example of a middle ground in the conflict, though the novel still makes it clear that this is temporary and not something that can last long-term.