Questions & Answers about Птица там? Нет, она здесь.
Why does the translation say 'Is the bird there?' when there is no word for 'is' in the Russian sentence?
In Russian, the verb 'to be' (am, is, are) is almost always skipped in the present tense. To make a yes/no question without question words like кто (who) or что (what), you simply use the exact same words as a statement and raise your voice's pitch on the word you are asking about (in this case, там).
Since the bird is an animal, why do we use она (she) instead of an 'it' pronoun?
In Russian, pronouns always match the grammatical gender of the noun they replace. The word птица (bird) ends in -а, which makes it a feminine noun. Even though we usually say 'it' for animals in English, you must use the feminine pronoun она in Russian.
How would I change this sentence to ask 'Who is there?' or 'What is there?' using this lesson's question words?
You would just replace the noun птица with the question word you need. To ask about a person, say Кто там? (Who is there?). To ask about an animal or an object, say Что там? (What is there?).
Do the words там (there) and здесь (here) change if the noun is masculine or neuter?
No, they don't. Words that describe location like там and здесь are adverbs. Unlike adjectives, they never change their endings to match the noun.