Being sentient means to have the capacity to have positive and negative experiences, such as feeling pain and pleasure. This applies at the very least to all animals with centralised nervous systems. Sentient beings have their very own unique personalities. We should refer to them as “he/she”, “them/they” or by species. The words “it” or “thing” should not be used to refer to an animal, and “who” is used rather than “that”. If you do not know the gender, then choose one: “he” or “she”. Even if your gender choice is wrong, it is more respectful than “it”. This is an important way of demonstrating the respect we ask others to afford all animals.
The answer to this questions depends on ethical values and how these are applied by both, the finder of a bird in need of help and the rescue or rehabber taking over its care. The need for a suitable environment, a suitable diet, to be able to exhibit normal behaviour patterns, to be housed with or apart from other animals and to be protected from pain, suffering, injury and disease are just a few very basic animal welfare standards, which should always be taken in consideration. In addition to these animal welfare standards, there are further ethical values to consider, which have to be evaluated to be able to give a thorough answer to this question.