Halloween is around the corner, which means it’s time for this year’s edition of Meet Our Monsters! The oceans are full of creepy creatures with freaky skills that seem eerily unnatural.
The sarcastic fringehead defends its territory by adopting a new, menacing look. First it flexes its body, extends its gill covers until they pop up like an umbrella, and then snaps its jaws. Flickr Commons Photo by Ken Bondy
Halloween is around the corner, which means it’s time for this year’s edition of Meet Our Monsters! The oceans are full of creepy creatures with freaky skills that seem eerily unnatural. From regenerating organs to exhibiting a monstrous display to ward off intruders, these monsters are freaky enough to give any ghost or ghoul a run for its money.
Sea Cucumbers
These soft-bodied echinoderms may seem unassuming, but this is one invertebrate most predators won’t want to mess with. There are over 1,200 species of sea cucumbers, named for their resemblance to the popular vegetable. By touch, sea cucumbers are slimy, soft and squishy, although they have microscopic spiny plates far beneath the surface of their skin. These cousins to the popular sea star can range in size from about an inch to six feet long.
Predators beware—this sea vegetable isn’t going down so easily. When threatened, some species can self-eviscerate parts of their own body by violently contracting their muscles and secreting their organs out of their anus. This tricks the predator into thinking the sea cucumber is dead, and while the predator is distracted by the organs left behind, the sea cucumber takes the opportunity to sneak away and later regenerate these lost organs. Other species have the ability to discharge sticky threads that contain a deadly toxin called holothurin, ensnaring and thereby turning the tables on the would-be attacker.
Sarcastic Fringehead
This freaky fish is no joke. The sarcastic fringehead gets its name in part for its temperament, as it is extremely fearless and fiercely territorial. These solitary fish aren’t exactly picky about where they live, inhabiting a variety of establishments such as empty clam shells, abandoned burrows, worm tubes and even man-made trash like beer bottles. There’s even an area in Santa Monica Bay known as “beer bottle field” where a sarcastic fringehead is found in nearly every bottle in the water.
While they may not be extremely particular about what sort of home they inhabit, once they’ve found it, they won’t give it up without a fight. This fish doesn’t care about the size of its intruder; if something is coming after its territory, it will fight back.
The sarcastic fringehead defends its territory using a variety of maneuvers. To start, it sends a series of warning signals by adopting a new, menacing look. First it flexes its body, extends its gill covers until they pop up like an umbrella, and then snaps its jaws. This process gives the fringehead a startling appearance that resembles the terrifying frilled-neck, venom-spitting lizard from Jurassic Park (minus the venom-spitting), indicating that the fish is not to be messed with. If this scare tactic doesn’t work, the fringehead uses its sharp, needle-like teeth to bite its intruder. If the fight is between two fringeheads, they embark in a “mouth wrestle,” pressing their distended mouths against each other, almost as if they were kissing. This isn’t an act of affection, however. Having extremely poor eyesight, this interchange lets them know which one is larger, and therefore who has dominance.
Sarcastic fringeheads have long, slender, scaleless bodies with large heads, wide jaws and large lips and are generally quite goofy looking when they aren’t playing defense. They vary in blotched coloration from black, brown, gray, purple, green or red. Typically reaching lengths from three to nine inches, sarcastic fringeheads boast wavy appendages over their eyes called cirri—this is the origin of the fringehead part of their name.
It’s fairly rare to see a sarcastic fringehead swimming for long periods of time, as this is not their strong suit. For the sarcastic fringehead, swimming mostly consists of short, erratic darting movements that often involve many quick changes of direction in which they are employing different combinations of fin manipulations.
You can find out more about these underwater monsters and other freaky fish of the Bay in person at Aquarium of the Bay. From October 30 to November 2, Aquarium of the Bay will celebrate Halloween with special presentations focused on all of our favorite “monsters.” Find out more at www.aquariumofthebay.org.
Mallory Johnson is the Public Relations Coordinator for Aquarium of the Bay, a nonprofit organization dedicated to protecting, restoring and inspiring the conservation of San Francisco Bay and its watershed.
