Right now, this bear is catching fish. It needs to catch fish to live, because each organism needs food, water, shelter, and space. The bear eats the fish for food. It is also in its space.
These bears are getting water right now, because it needs water to keep it living and hydrated. Just like we couldn't live without water either, right? These bears have a hydrating system like us, too.
Right now, this bear is in it's shelter. It needs shelter to live and sleep. Imagine if you couldn't sleep. You couldn't survive! Bears have feelings too, you know!