sentences:  At the time, the frog was the only species to receive an "emergency listing" as an endangered species in Canada.The zoo is currently still involved with this program, releasing frogs into the wild after they are weighed, measured, and tagged.Furthermore, many animals have been rescued over the years and eventually released back into the wild, but some animals like "Shadow", a grizzly bear, could not be returned because she had been abandoned as a young cub and was not able to learn the skills needed to survive in the wild.