Honolulu Star-Advertiser © Susan Scott
January 15, 2001
Here’s a recent e-mail question from a mainland visitor:
“While on Kauai, I was walking in a shallow tide pool in about 2 inches of water when I saw what I think was a banded snake eel. It darted into the sand head first. I read that banded snake eels burrow tail first but I swear that what went in last was a tail. Your thoughts?”
My thoughts are: We have banded snake eels? I’ve never seen one here (or anywhere else for that matter) and my Hawaii fish books don’t mention them.
But according to the eel expert at the Waikiki Aquarium, we do have these fish — sort of. Hawaii hosts a type of eel closely resembling the banded snake eel. Here it’s called the half-banded snake eel; in other parts of the Pacific, it’s called the saddled snake eel.
The names half-banded and saddled are both appropriate for this eel because the wide brown bands on its white body are incomplete. They go down both sides but not under the belly. You can’t see this when looking down at the creature though and it would be easy to mistake it for a banded snake eel.
Both banded and half-banded snake eels are non-venomous fish, but they closely resemble the banded sea snake. In areas where this highly venomous reptile lives, hungry fish and birds may pass up the half-banded eel, mistaking it for the deadly snake. Sea snakes aren’t fooled by this ruse though. In Japanese waters, banded sea snakes have been spotted eating half-banded snake eels.
We don’t have banded sea snakes in Hawaii. If you see a snake-like body, about 20 inches long, with wide brown stripes on a white or yellowish body it’s always an eel. But you won’t see one often. Half-banded snake eels are hard to find because they spend most of their time hiding in the sand. Occasionally they emerge, however, day or night, to hunt.
Most snake eels actively search for prey by rummaging around in cracks and crevices or under sand. Some, however, bury themselves up to their eyeballs and ambush passing prey. This works well in these species because their eyes are on the tip of their snouts making them practically invisible in the sand.
One such ambush species in Hawaii is the crocodile snake eel. This relatively common creature has a grimacing face like that of a crocodile and a wicked bite to go with it.
Crocodile eels rarely leave their holes, a fact that underwater photographers should remember. A crocodile snake eel bit at least one isle diver when he inadvertently lay on the creature while taking a picture.
But back to half-banded eels. In the Red Sea, half-banded snake eels have been seen eating garden eels by a method that sounds like a science fiction story.
Garden eels are famous for anchoring the lower parts of their bodies in sand burrows and waving their heads and upper bodies around to feed. These endearing little eels live in colonies and look like flowers swaying in a breeze.
This peaceful-looking garden, however, has enemies below. The half-banded snake eel sneaks under the sand to a garden eel’s burrow and eats its unsuspecting prey from the tail up. Snake eels are known for their rigid tails that enable them to dig backward in the sand. But the garden eel story proves that snake eels, at least half-banded ones, are also quite capable of burrowing headfirst.
The Kauai visitor wrote that she spent two hours on the Internet looking for her tide pool creature. Her persistence led to a good guess and an equally good question.