Tame a high level one of these, get it a saddle, then get a snail, then get some fur armour, give the snail enough food to survive the trip, then pick up the snail go on your bird and go to the north and kill baby penguins while on your bird, then get off the bird and transfer the organic polymer from the bird to the snail, I have gotten hundreds of polymer this way. ^^
To the people who are annoyed about the fish diet, Pelagornis can float on the water and swim with you on it instead of getting dismounted forcefully like any other flier. They can murder fish that way if you have a few minutes of your time and a good, lively pond or river.
Mine was killed by a Xiph (Ark Additions creature, mod) and she was the best otherwise.. thank you for reading and Midnight also thanks you for taking another one like her! 🪶