This is the 4893rd most frequent Korean word.
구출된
"Rescued."
In this sentence, '구출된' is functioning as an adjective modifying the noun (animals), emphasizing the condition of the animals having been saved.
구출된 동물들이 자연으로 되돌아갔다.
The rescued animals returned to nature.
Here, '구출된' specifically refers to the scenario of their rescue, used attributively to describe the situation.
그들은 구출된 상황을 고맙게 여겼다.
They were grateful for the situation where they were rescued.
Here, '구출된' is used as a past participle adjective to describe the state of the subject (he) having been saved.