Monthly Archives: January 2015

Fish? Fish? What fish?

We managed to get into the water a couple of times following our month on the mainland (see Florida post) and another month down with bronchitis, but prior to the last couple of weeks’ big waves.  Swimming with Marilyn (more on Marilyn in a later post) earlier in the month, Marla spotted a devil scorpionfish in about fifteen feet of water.  These guys are apparently quite common, but we only see them occasionally.  With their highly camouflaged  coloration, they are almost impossible to spot except when they’re moving, which they usually are not.


Devil Scorpionfish. Note the large hump on the back, a feature that distinguishes this species from other scorpionfish.

I surmise that the devil scorpionfish is so-named because of the bright orange-yellow pectoral fins that the fish displays when alarmed.  Hoover, Randall, and Stender all have good photos of this, but I haven’t managed to take one of my own yet.

All scorpionfish have poisonous spines and are dangerous to step on or handle.  I have on at least two occasions spotted devil scorpionfish lurking within just a few feet of the swim ladder at Mahukona, but I’ve never heard of anyone being stung by one there.  Just luck, or is it that the fish are alert enough to swim out of the way as an unsuspecting foot descends upon them?

scorpioneyeHere is a closeup of the eye of a devil scorpionfish. Even the pupil is camouflaged, being irregularly shaped rather than round.  Optically speaking, a round pupil is always more efficient than any other shape, as evidenced by the preponderance of round pupils in other fish, and in animals in general.  For these cryptic ambush predators it’s apparently worthwhile to take a small loss in visual acuity for the sake of better camouflage.

The flowery flounder is another cryptically patterned fish that we occasionally see at Mahukona.  As with the scorpionfish, we only spot them when they are moving.  They have a graceful, undulating swimming motion that is a pleasure to watch.  It is surprising how rapidly they can swim when disturbed, darting several feet forward and then quickly blending into the bottom.  These fish also have non-circular pupils.


Flowery Flounder near the Mahukona dock

Mahukona destruction

A series of storms off Japan have been producing large swells along the western shores of the Big Island on and off for the last couple of weeks.  The waves have done a lot of damage at the Mahukona dock, destroying part of the seawall and tearing up the surface of the parking area. These conditions are hard on nearshore marine life too.  While the fish can just swim out to deeper water, less mobile creatures—corals, sea urchins, sea cucumbers, etc.— have to hunker down and bear it.  In addition to the force of the waves themselves, the bottom is pummeled by the large coral boulders that are tossed around by the waves.  After a similar event in 2013, many broken off coral heads could be seen in water up to fifteen feet deep.  The broken tips have just begun to “heal,” only to be whacked again.  Life in the impact zone…


A wave crashing into the Mahukona boat lift, which was badly damaged in a similar 2013 storm event


Looking north


The boat lift on a better day