The original sentence you wrote is: A Namaqua sandgrouse soaks its feathers with water to take it back to its thirsty chicks.
This sentence is mostly correct, but there is a small issue with the word "it." The word "it" should refer clearly to the water, but since "water" is a non-count noun, it's better to say "take the water back."
A clearer way to say the sentence is:
A Namaqua sandgrouse soaks its feathers with water to take the water back to its thirsty chicks.
This way, the meaning is clearer and the grammar is correct! The sentence tells us that the bird soaks its feathers to carry water back to its chicks who are thirsty.