Beachcoming at first light yields treasure

September 05, 2003

I am one of the few people I know who can get a stiff neck and sore back from walking the beach.  I give myself these aches because I spend most of my stroll looking down at the sand to see what’s washed in.

This love of beachcombing is one of the passions that drove me to study marine biology.  I wanted to put names to my finds.

Last week, I indulged in my scavenging obsession at Kailua Beach.  The trade winds had been blowing hard for days and the tide was lowest at first light.  At dawn, I headed for the water.

Because the wind often blows directly toward land in Kailua, its beach can be a giant treasure chest.  This time I hit the jackpot.

For the first time ever, I found a stranded mantis shrimp.   The live, 3-inch-long creature lay on its back just above the surf line.  The early morning sun caused the shrimp’s red, pink and green colors to shimmer.  The shrimp’s big, compound eyes wiggled on their long stalks.

Since mantis shrimp’s first two claws fold neatly under their bodies like switchblades, I didn’t touch the dying creature.

I moved on and soon had another first find: a baby cornetfish.  This trumpetfish cousin has a long narrow snout, a long narrow body and a long narrow filament trailing from its tail.  I’ve heard people call this filament a stinger, but it is not.  It’s a soft, flexible strand of flesh.

Cornetfish grow to 5 feet long, but even so can be easily overlooked.  It seems pretty hard to miss a 5-foot-long fish, but cornetfish are so skinny and so color-camouflaged, you can easily swim past one and never know it’s there.

Cornetfish (Spencer Tinker, “Fishes of Hawaii”)

Cornetfish eat other fish almost exclusively and that’s why I was so interested in examining the dead cornetfish’s snout.  At first glance, this slim snout seems to be two long, closed jaws, like a needlefish beak.  Cornetfish snouts, however, are actually narrow tubes ending in small mouths that contain tiny teeth.

Neither mouth nor snout nor teeth look like they could handle anything but the most miniscule fish.  Cornetfish, however, have tricks up their snouts.  This fish’s jaws and mouth are capable of enormous expansion, and the bottom of the snout is elastic.  The tubemouth, then, can inhale fish larger than seems possible.  And I mean inhale.  Cornetfish catch fish by sucking them in, pipette style.

After the cornetfish, I moved on.  Here’s what else I saw:

• An adult male frigatebird riding the wind, two wedge-tailed shearwaters shearing the water and a wandering tattler pecking along the surfline.

• About a hundred small Portuguese man-of-wars.

• A mole crab (locally known as sand turtles) grabbing the tentacle of a beached Portuguese man-of-war.

• About a hundred ghost crabs of all sizes.

• A big ghost crab eating a dead manini (convict tang.)

• A sea cucumber caught in a pile of seaweed.

• A moray eel caught and discarded by an angler.

• A bottle covered with dying gooseneck barnacles.

  I enjoy snorkeling and diving, but for me, nothing beats a solitary walk on a windward beach at first light.  Sand biology suits me.