Build a small pen. Place a bunch of AC and tame around 30 penguins and put them wander so they lay eggs. Then trap pelagornis in room so everytime the penguins hatch the pelagornis will gather the body's polymer
Ever need lots of raw fish. Easy! Instead of swimming around in the water risking getting attacked by megapiranhas, simply make a saddle for your Pelagornis, Ride it into the water, and it one shots every small fish.