My first atoll

On Thursday I joined the Berkeley class for a trip to Tetiaroa, an atoll located two and a half hours north of Tahiti and Mo'orea. The atoll is famous for having been owned by Marlon Brando. We (22 students, three TAs, one professor, and three other station people) were picked up by a fleet of four fishing boats on an overcast morning at 7 from the Gump Station docks. The boats made a show of racing each other out of the lagoon just to show off, but once we were out on the ocean, it was surprisingly calm, almost like a lake. As we zoomed along in the cool morning we watched flying fish jump out of our wake and buzz along over the surface of the ocean, with brown boobies in pursuit. We saw one booby crash-land into the water to successfully grab a flying fish, and another pair fight over another (to the benefit of the fish, which managed to escape from the booby's bill). After about an hour, we began to see the islets (motu) that make up the atoll of Tetiaroa in the distance along the horizon. Like all atolls, Tetiaroa consists of a sunken volcano around which a coral reef has developed right below the surface; in places, the sand and coral rock piles up to form little islets, called motu in Tahitian, which support plant life, and in the case of Tetiaroa, bird and sea turtle nests as well. Cheese trees only grow on high islands or uplifted atolls, so I had never been to an atoll before in French Polynesia.

There is no pass through the reef for boats to enter the lagoon of Tetiaroa, so we had to jump out of the boats, swim up to the edge of the reef, let the swell carry us up onto the reef (in only a few tens of centimeters of water) and stand up. This was actually easier than it sounds, but I got some impressive coral cuts on my legs regardless. We then walked across the reef (carrying our gear on our heads, because the water was sometimes chest-deep) and came ashore on the motu.

The beaches of Tetiaroa are blindingly white, and the motu support thick groves of coconut palms thanks to the now-defunct copra industry. The lagoon is placid and sandy, and colored pale turquoise. It all looks like the kind of place you only see photos of, the kind of place you don't really believe can exist. We saw blacktip sharks in the lagoon. We saw all sizes of hermit crabs on the beach. We saw a humpback whale breach, repeatedly, against the backdrop of Tahiti in the distance. We saw a Polynesian rat approach us as we were eating lunch on the beach. We walked across the lagoon to a motu lacking rats, home to hundreds if not thousands of nesting brown noddies and brown and red-footed boobies and sooty and great-crested terns. We saw a white Pacific reef-heron (a species I had first seen in Okinawa) and a flock of bristle-thighed curlews (on vacation from their breeding grounds in Alaska) fly by. The sandy floor of the lagoon is littered with thousands of black sea cucumbers, looking as though somebody had left unpaired black socks everywhere. There is a movement afoot for the French Polynesian government to designate Tetiaroa as a protected area; it certainly deserves it.

After lunch, a few of us snorkeled over the reef and then let the swell carry us out to the ocean side of the reef, where we looked down at a sheer wall of calcium carbonate and the collapsed rubble a hundred meters below where an ancient piece of the reef had broken off and slid downslope. It was the most amazing visibility I had ever seen in my life. We drifted close to one of the fishing boats, and when I stuck my head out of the water, someone in the boat asked if we wanted to see whales. A bunch of us piled in the boat, and we puttered around off the reef until we saw a whale blow. We jumped back into the water and for a few minutes, as our eyes adjusted to the blueness, watched a mother humpback and her calf sleeping at the surface. The baby was huge, but looked like a little half-sized replica of its mother. There was a huge white remora attached to the belly of the calf. They woke up, and the mother dove vertically a hundred meters below, to a point where we could only dimly see the white outlines of her flippers and belly, to realize that she was hanging vertically and head-down. We piled back in the boat, this moment seeming too brief.

After about ten minutes of puttering around some more, we saw the mother and calf at the surface again. This time again we got back in the water, and the whales stayed at the surface longer. Underwater it was impossible to judge distances; by sticking my head back above water I could see how close we actually were. Both the mother and calf dove again after a few minutes, but this time we could see the mother essentially lying on her back in a three-quarters pose a hundred meters below, wing-like flippers outstretched. The calf was lying alongside her mother, and then turned perpendicularly to nurse from her mother's teats. As the mother remained below "upside down", the calf ascended to the surface to breathe and look at us, and returned below to her mother. The most unexpected thing was the realization that whales do not necessarily orient themselves "right side up" like their terrestrial ancestors when they are resting underwater. They have broken free of the constraints of gravity on their ancestors. Looking down in the water at the mother nursing her calf, I could contemplate the grand sweep of mammalian evolution: here are the mammals that broke free of gravity and dry land. They became the only of their kind to reach the south Pacific, until these other mammals at the surface evolved the intelligence and the dexterity to build devices to carry them over the oceans, to let them look through the water at the other mammals and wonder what their lives must be like. It was one of the most sublime experiences of my life.