Amazing Sea Hares from Anilao Pier

Anilao Pier, home to the notorious bobbit worm, is my favorite site in the Philippines for night diving. I first dove here in 2012, during my graduate studies at San Francisco State University and the California Academy of Sciences. The diversity of marine invertebrates here is astounding, especially with respect to sea slugs, snails, and anemones. I’m particularly interested in sea hares, a group of sea slugs in the order Anapsidea. They’re called sea hares thanks to the horn-like structures on their head, known as rhinophores, which allow them to sense their environment—and which happen to resemble rabbit ears. Like the nudibranchs they’re related to (same phylum, different order), sea slugs have evolved potent chemical defenses to deter predation, since they’re soft-bodied and possess either a reduced shell or no shell at all. On one of my night dives during the expedition, I came across two beautiful, large, lime-green sea hares crawling through the sand and sea grass about 3 meters down. Overwhelmed with excitement upon spotting them, I actually squealed through my scuba regulator! I picked one up and let it go, watching it swim gracefully with its wing-like dorsal appendages (called parapodia), and later collected both for the Academy’s sea slug collection. This was my first encounter with a species I later learned was Syphonota geographica, the only species within the genus Syphonota. Despite it being circumtropical (distributed throughout the tropics) and an invasive species in the Mediterranean, the Academy’s Senior Curator of Invertebrate Zoology, Terry Gosliner, had only encountered this species once before in the Philippines. I’m thinking about investigating its taxonomy and chemical composition for my PhD, since it may actually represent more than one species and contain variable chemical composition, depending on where it’s found and what it eats. Syphonota geographica in the Indo-Pacific have been reported as feeding on brown algae, while those from the Mediterranean are considered specialists, feeding instead on the invasive seagrass Halophila stipulacea. Representatives from Greece have been studied chemically, but specimens from the Philippines haven’t been researched—offering a great chance to add another chapter to our understanding of the area’s biodiversity. —Carissa Shipman, PhD student at University of the Philippines Diliman

“Like Something Out of a Nightmare”

There are two Academy groups currently in the Philippines for the 2014 Biodiversity Expedition: one from Research, and the other from the Aquarium. Though we’re staying at different locations, we collaborate when we can, like tonight. It all started with a 90-minute night dive at Anilao Pier to try to collect a Bobbitt worm—a creature that lives in the sand, has jaws like a bear trap, and might be several meters long. It shoots up with lightning speed to catch fish and other animals, yanking them down into the muck like something out of a nightmare. In the 1990s, Academy Senior Curator Terry Gosliner named the Bobbitt worm after Lorena Bobbitt (and her legendary attack on her husband), and Academy crews have been trying to collect this animal both for display and for our preserved collection ever since. One look at the photo shows you why catching this animal isn’t easy, but take a look at this video for an even better demonstration. Tonight’s effort was unsuccessful, though I did get my hand on one of the worms—yes, my hand. My wife is less than thrilled about these attempts, but she understands that we have to do what we have to do for science. More efforts are planned, and hopefully there will be success. Hopefully. After the worm hunt, there was a party—a party that started without us. Apparently it began with a whole roast pig (enjoyed by both Research and Aquarium Staff), but by the time the worm hunters arrived, things had changed drastically. Let’s just say that while there was still much fun to be had, there wasn’t much pig. Expeditions like this are an amazing amount of work, similar to running a triathlon. Instead of the events being swimming, running, and biking, the events are collection, processing, and animal care. The endurance needed to put out so much energy every single day is huge, but it’s also incredibly fulfilling when everything’s going well. Tonight’s party was a short break from the draining but rewarding work of the expedition … and the only picture I can find of the event is this one of me gnawing on a pig’s head. Ah, science—we love you. —Rich Ross, Aquatic Biologist
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