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Writer's pictureRyan Dibala

Aristotle's Lantern

The island has been shrouded in fog for most of the morning, but now the thick marine layer is dissipating rapidly over the north ridge. It’s as if a curtain has been pulled for the first number of a Broadway show and all its thespians have suddenly revealed themselves. Christy beach is the scene, and I sit on a grassy bluff looking out over the Great Blue, counting the seconds between each tumbling swell. The surfing would be good today if I only knew how to surf. If this weren’t California, it’d be alright if I didn’t know how to surf; I’d just get in the water and try my luck on the longest board I could find, for beginner’s sake. But this is the California Current – the rushing chill – where a tincture of ice is ubiquitous in each momentous surge of upwelling.



Last year I wearily dragged a surfboard behind me after spending time in the frigid waters of Shark Harbor on Santa Catalina Island. I shook the water out of my ears, trying to rid myself of the cold seeping into the marrow of my bones and looked back at the crashing waves. I remember feeling an intense pain in my right ear all throughout the next day and wondered how people could glean even the slightest amusement from such an inclement experience. Maybe it’s because they’re well equipped with with booties and a hood in addition to their wetsuit.


The marine life of Channel Islands National Park is bountiful. Tide pools are like botanic gardens, only where plants are replaced with Echinoderms, Bivalves, and Cnidarians. Here, several Ochre Sea Stars (Pisaster ochraceus) share a substrate with thousands of mussels


The giant bladder kelp (Macrocystis pyrifera) beds that line the shores of the Channel Islands say something about the uncomfortably cold currents here in southern California. These towering brown algae can only tolerate water temperatures between 55 and 60 degrees Fahrenheit and will die if the waters are any warmer. In 1997, an El Niño southern oscillation event warmed the waters to such a degree that many of the kelp forests perished along with its many residents. California Sheephead (Semicossyphus pulcher), Garibaldi (Hypsypops rubicundus), Señoritas (Oxyjulis californica), and various species of bass no longer found refuge in the dense, underwater sanctuaries. Beaches began to suffer greater impacts of erosion due to the absence of these offshore buffers and the uprooted holdfasts of the 200-foot serpent tongues drifted in with the passing tides.


The Pacific purple sea urchin (Strongylocentrotus purpuratus) is not only an important part of the ecosystem, it is also being studied for answers to questions regarding longevity. This species has the ability to regenerate damaged or aging tissue and could provide clues on how possibly even a human body could return to a more nascent state

I’ve often sat, looking out at the vast, mystical ocean wondering why I’m not watching California sea otters (Enhydra lutris nereis) playfully floating on their back atop glassy waters, using rocks to break open obstinate urchins. It was in the 18th and 19th centuries that these charming mustelids were over-harvested as a result of the fur trade and it wasn’t until 1938 that a remnant population off of Big Sur was discovered. This small population has now expanded its range due to preservation efforts and can be found from San Nicholas Island in the south to Año Nuevo Island in the north. San Nicholas Island is one of the Channel Islands, but it is relatively remote, and the remaining islands have yet to be graced by the presence of the sea otter. Without the predatory influence of the sea otter, sea urchin populations can burgeon and overgraze kelp forests, chomping them to the bit with their mouth apparatus with a shape that Aristotle likened to a lantern. Thus, an ecological trophic cascade ensues, where the otter’s absence ultimately leads to the demise of the entire kelp forest.


The western gull (Larus occidentalis) is the most abundant breeding seabird of the Channel Islands, estimated at more than 15,000 individuals. They nest on rocks along the islands and coastal beaches


Nowadays, urchin fishermen have fulfilled the sea otter’s role. On our occasional journeys around the islands in our 8-foot zodiac motorboat, we have seen a good deal of urchin boats and their divers out around rocky shoals. Out of three species (the green, purple, and red), the red sea urchin (Mesocentrotus franciscanus) is what is most sought after and it is found in the deepest water. Predatory control of these rapidly multiplying Echinoderms is also instated by the spiny lobster (Panulirus interruptus). Different from its Atlantic counterparts, the spiny lobster has no front pincers and defends itself by thrashing its muscular tail and whipping its pair of serrated antennae. It also feeds heavily of California mussels (Mytilis californianus), which vacate rocky areas and makes them available for colonization of organisms like the giant kelp.


Kelp (Macrocystis pyrifera) forests can be seen beneath the waters several hundred yards offshore


I wonder if an overwhelming human presence can ever really take the place of what's inherently natural? Does man's presence in the urchin fishery adequately fulfill the predatory niche of the sea otter or does it leave something to be desired for the top-level predators like the orca that depend on healthy populations of marine mammals? We can always decorate our words and attempt to justify such an endeavor, but there is always the great risk that our actions will take a toll that bestows no reparation.






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