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Komodo National Park

Snorkeling to see sea slugs in Komodo National Park


Bornella anguilla - coral triangle adventures


By the end of the recent Coral Triangle Adventures trip to the Komodo National Park and surrounding islands the intrepid guests would have no doubts about the propriety of my self-designated “nerdibranch” moniker, as I effused endlessly about nudibranchs and other sea slugs. These shell-less relatives of snails exchanged the protective coverings of their ancestors for the deterrent effect of toxic or noxious chemicals. Many announce this line of defense to would-be predators with brilliant warning colors, a phenomenon known as aposomatic coloration, while others use camouflage to avoid detection. Despite their often-conspicuous markings, the small size of many nudibranchs and other sea slugs admittedly makes it challenging to find them while snorkeling. Understandably, the manta rays, giant cuttlefishes, sea snakes, and the dazzling diversity of tropical reef fishes observed in the Komodo NP area are well deserving of our guests’ attention and appreciation, but it can also be satisfying to occasionally engage in a sea slug scavenger hunt. Once a nudibranch is discovered one can then wonder at the other-worldly beauty of these sometimes-bizarre life-forms that seem like they would be more expected in the underground seas of Europa than in the oceans of our own planet. The bumpy Phyllidiids and the sea squirt-eating Nembrotha species were among the nudibranchs most commonly observed by guests on this recent trip. Highlights included Bornella anguilla, a psychedelic-patterned nudibranch that can swim like an eel, spotted by Ethan at Sangeang volcano, and a pair of leopard-spotted nudibranchs, Gonibranchus leopardus, observed at Satonda.

Lush reefs can be found throughout Komodo National Park - coral triangle adventures


But as a coral reef ecologist who has seen first-hand the devastation that coral bleaching, crown-of-thorns seastars, sedimentation, and overfishing have wreaked on reefs in some parts of the Indo-Pacific, the breathtaking undersea vistas we encountered were also soul-stirring. One could spend hours marveling not just at the myriad forms, colors, and behaviors of the reef’s denizens, but also at the enveloping beauty of the sites and sounds that wash over you. The dance of light on the seafloor; the extensive, tangled thickets of staghorn corals; the pulsing schools of irridescent Chromis; and the profusion of pops, snaps, and grunts visually and audibly announce to visitors that this reef community is thriving—and from the coalescence of these elements emerges the intangible, indescribable gestalt of a vibrant coral reef. These stunning seascapes manifest in innumerable forms, each influenced by the unique environmental conditions and assemblies of life found at each site. Beyond experiencing the spectacular beauty of hard coral-dominated reef areas one would expect from the Coral Triangle, like those at Gili Davat and Gili Banta, visitors to the Komodo NP and surrounding islands also get to take in the striking contrast of colorful hard and soft corals against the black sand at Sangeang volcano and wind between the astoundingly rich sea grass beds and mangroves of Tatawa. The beauty of these diverse habitats, and the profusion of life they support, are what draw us to Coral Triangle locales such as the Komodo National Park and surrounding islands. From sea slugs to seascapes, CTA’s Komodo snorkeling trip has it all.