Butterflyfishes on a North Kohala reef

by B. N. Sullivan

Of all the reef fishes in Hawaii, those that belong to the Butterflyfish family (Chaetodontidae) are perhaps the most colorful and easy to recognize.  About two dozen species of butterflyfishes live in the waters around the Hawaiian Islands.  The photo at right shows two of those species. [Click on the photo to enlarge.]

This photo is dominated by a grouping of Pyramid Butterflyfish (Hemitaurichthys polylepis).  Their common name refers to the triangle-shaped white patch  that covers most of their bodies.  These plankton eaters tend to aggregate over stands of coral during daylight hours, just as you see in the photo.  Pyramids are native to the central and western Pacific Ocean.

In the lower left quadrant of the photo are some Milletseed Butterflyfish (Chaetodon miliaris), named for the vertical rows of black seed-like dots on their otherwise yellow bodies.  They also sport a prominent black ocular bar (eye-stripe) and a black blotch at the base of their tails (i.e., the caudal peduncle).  They, too, eat plankton, but sometimes a diver or snorkeler will see a Milletseed Butterflyfish cleaning other fishes.

The Milletseed Butterflyfish is a Hawaiian endemic species -- that is, they are found naturally only in the Hawaiian Islands.  They are quite plentiful along coastal reefs, so if you snorkel or dive in Hawaii, you are very likely to see these fishes.

The photo on this page was taken at Big Sandy, a dive site located a few miles north of Kawaihae, on the North Kohala Coast of the Big Island.


  1. The butterfly fish are distinctive (I did notice the two varieties) - their shape suggests "tropical fish", i.e., the typical shape of a reef fish.
    Of course, the contrast between the orange and blue also caught my attention.

  2. Oh, and in response to your comment on our recent post "Sam Evolving", we do have a post entitled "kitten on the keys" from last year :)


  3. OK, it has officially been too long since I was out diving. This coming weekend is out, I am on call. The next weekend however...

  4. @ catsynth - I did go and have a look at your kitten-on-the-keys. ;-}

    @ Andrew - Get thee to the ocean! :-D


  5. Wonderful image and info Bobby, they are beautiful, starting to get a little cold here I sure would love a warm swim now !!

  6. "the caudal peduncle"

    And I always thought it was just an eye spot.

  7. Wes and I are driving across the saddle road tomorrow to snorkel! Great informative post~ inspiring too.

  8. Don't know why, but I haven't been here in a while. I lose because your pictures and history are amazing. Such a beautiful fish!


We welcome your comments and invite your questions. Dialogue is a good thing!

Bobbie & Jerry