The sentence you gave is mostly good, but there are a couple of small things to fix to make it clearer and correct:
Original sentence:
Baby chicks often start out with fuzzy feathers that easily get wet. So, like many water birds, swans taxi their chicks around on their backs till they are ready to swim.
Corrected sentence:
Baby chicks often start out with fuzzy feathers that easily get wet. So, like many water birds, swans carry their chicks on their backs until they are ready to swim.
Explanation:
- The word "taxi" is usually used for airplanes moving on the ground. For animals like swans, "carry" is a better word to use.
- Instead of "till," the full word "until" sounds more clear and formal.
So, the corrected sentence says that baby chicks start with fuzzy feathers that get wet easily, and swans carry their chicks on their backs until the chicks can swim.