The neverending story

You are a dolphin.
Your faster than the fish, and are able to catch, and eat several of them. Wow! These are good! Fish never tasted so good when you were human!
After you've eaten your fill, you continue on, riding the warm current whereever it leads.
Swimming along for a couple more hours, you can almost make out something on the ocean floor. It's a faint green glow, and it seems to cover several kilometers.