Wolfie and the otters

My readers know how much I love otters. Well, my wife and I discovered recently that Wolfie does not share yet this love. We recently visited a sort of mini-zoo that has a number of exotic and local animals. Including otters. (But not the otter on the picture: I took this particular photo in the otters sanctuary that we visited a few years ago in Buckfastleigh, in Devon.) While Wolfie loved quite a few animals, when he saw the otters there he looked pitifully, cuddled up to us and said in a small voice "bit scared". We had to go away. I wonder why he was scared of the otters there and not of other, bigger animals. Maybe there is something predatory about their attitude?