After the environmentalist showed his slides of the retreat of Arctic glaciers, he expressed his fear for polar bears, which are losing a large percentage of their natural habitat.
After the environmentalist showed his slides of the rertreat of Arctic glaciers, he expressed his fear of polar bears, which are losing a large percentage of their natural habitat.
After the environmentalist showed his slides of the rertreat of Arctic glaciers, he expressed his fear for polar bears, which are losing a large percentage of their natural habitat.
After the environmentalist showed his slides of the rertreat of Arctic glaciers, he expressed his fear of polar bears, which are losing a large percentage of their natural habitat.
The idiom "fear for X" means someone perceives X as vulnerable, as threatened by some external danger. This is a posture of protective concern for X, very different from being afraid of X. That is appropriate here. The idiom "fear of X" means that someone perceives X as a danger or threat and thus regards X with fear, not concern.