Found in most oceans of the world, butterfly fish are small, thin, disk-shaped fish with pointed noses. There are many varieties, the four-eyed butterfly probably being the most common from New England to the Caribbean. Others include the spotfin, the banded, and the reef butterfly.
Many of these fish have a dark band running vertically through each eye. This helps the fish camouflage themselves on the coral reefs where they live. Most butterfly fish have pointed snouts, very useful for plucking out the small coral animals and getting into small crevices for tiny invertebrates which they feed on.
Yellow, white, and black are the most common colours for butterfly fish. The four-eyed is pale yellow or whitish, with a dark eye band and a large dark spot on the tail. To a predator, the tail appears to be the fish’s head and often allows the butterfly to escape being the “blue plate special” of the day. The spotfin is also yellowish and has a small dot at the base of its dorsal fin. The banded butterfly looks like a zebra, having alternating black and white stripes running vertically the length of its body. The reef butterfly starts with yellow at the top and fades to white on its belly. Most butterfly fish mate for life and raise their young together. Sometimes, if one dies, the other may also perish. Occasionally, there may be three to six in a small group.
These little fish are a delight to visit on a coral reef. They are usually busy pecking away at the coral and scurry quickly if disturbed; however, if you move slowly, it is possible to follow – and count them. One species resident in the area that you are unlikely to see, because of its preference for deep-water habitats, is the French Butterflyfish (Chaetodon guyanensis).
Species that you may see are as follows, with the list showing their maximum adult size:
- Banded Butterflyfish Chaetodon striatus 16cm
- Bank Butterflyfish Chaetodon aya 15cm
- Foureye Butterflyfish Chaetodon capistratus 7.5cm
- Longsnout Butterflyfish Chaetodon aculeatus 9cm
- Reef Butterflyfish Chaetodon sedentarius 15cm
- Spotfin Butterflyfish Chaetodon ocellatus 20cm