When I’m out snorkeling, some fish don’t seem at all bothered by my presence, continuing to go about their business. Others will dart away the moment I appear (nothing personal I hope). Bluespine unicornfish fall somewhere in between. Mostly when I see them they appear unconcerned, but the distance between us inexorably grows.

No prizes for deducing how they get their name.

In my attempts to identify what I see in the water, I use John P. Hoover’s book The Ultimate Guide to Hawaiian Reef Fishes, Sea Turtles, Dolphins, Whales, and Seals. His website is hawaiisfishes.com.