Honolulu Star-Advertiser © Susan Scott
March 1, 2010
In a project I’m working on, I briefly mention cowfish. Too briefly. An editor wrote in an e-mail, “Can you give us a closer look?”
Gladly. Cowfish and I have a long history.
Years ago I wrote the following about cowfish: “The common name of these tan fish with blue spots probably came from the ‘horns’ on their heads.” To which a critic replied, “Ridiculous. Cows don’t have horns.”
Um, cows do have horns. Most are cut off when the animals are calves or are absent through selective breeding. And cowfish have pointy spines that resemble horns.
Cowfish belong to an odd family called boxfish or trunkfish, so named for the rigid plates that form a four-sided suit of armor over the fish’s body. Boxfishes’ eyes, fins and kiss-puckered mouths protrude from openings in the square bodies, making the fish look like living, swimming suitcases.
If a boxfish is a suitcase, then the 6-inch-long spotted boxfish, a common species in Hawaii’s waters, is designer luggage. The male’s blue body is covered in white spots and trimmed in gold. The more rounded body of the female is also elegant in basic brown with white polka dots.
When our sailboat, Honu, was moored in the Ala Wai Boat Harbor, a male boxfish made occasional visits, nibbling algae and invertebrates that grew along the boat’s waterline. Besides being entertaining to watch, the little fish was also an indicator. When the boxfish stuck around all day grazing, it was time to clean the hull.
Male Boxfish
Female Boxfish – courtesy of David Schrichte
A close cousin of the spotted boxfish is the 5-inch-long thorny cowfish. This bovine beauty is tan with iridescent blue spots and lines. From its squarish body protrude five spikes, two at the rear, one on the back and two above the eyes that look like you-know-what.
While snorkeling on Hawaii’s reefs, it’s common to spot an adult cowfish paddling along the reef like a wind-up bathtub toy. When startled, cowfish sometimes swim backward, pointing their head spines at the intruder. If push comes to shove, cowfish (and all other family members) secrete a skin toxin.
Juvenile cowfish are rarely seen snorkeling because they swim offshore. There Hawaii’s gray-backed terns sometimes snatch them up to feed their chicks.
Grey-backed tern – Susan Scott
I once came upon a gray-backed tern nesting site. The chicks had fledged and the adults were long gone, but the birds left an astonishing gift: piles of juvenile cowfish.
I say astonishing because the armored plates of the miniature fish were still intact, but the bony interiors were clean of flesh. I don’t know if the parent dropped the fish and insects chewed in through the eye holes, or if the birds somehow digested the soft parts of the fish while leaving the hard parts intact.
Those walnut-size skeletons felt like gifts from the terns, and I brought a few of those treasures home.
Cowfish – Susan Scott
My history with cowfish continues. Last week, to better describe a cowfish, I placed one of those charming little fish on my computer monitor. Now there it sits, forever blowing me a kiss and reminding me what a Star-Bulletin editor once told me: “If no one is criticizing you, you’re not writing interesting stuff.” He also said, “Write about fish.”
I’m delighted to have readers so interested in my columns they take time to write. To those who sent such nice e-mails about last week’s humpback whale story, thank you. And to the Wahiawa reader: This fish story is for you.
Cowfish art – Susan Scott
Cowfish art – Susan Scott