As I write these lines, we are flying on a small plane bound to Honolulu. Our expedition to Kingman is finished. Most of our team is sleeping, reading, or listening to music in the only introvert environment of the last three weeks. The silence of the return flight contrasts with our excitement three weeks ago, when we were filled with anticipation. Today we are filled with experience and memories.

We just came back from our third dive. The sea was so flat that, if it hadn't been for little Isla Maxima, we would never have known we were on an atoll. The breakers were absent. All we could see was a spectrum of blues, the sky merging with the sea.

We were especially happy today. We have finished all of our data collecting, accomplishing more than we expected at the beginning of the expedition.

Last night was rocky; the Searcher swung with the swell all night long. That made us especially eager to jump in the water and dive a hundred feet below the surface, where the swell is barely discernible. We are tired after eighteen full days of diving, and waking up in the morning is increasingly difficult; but there is something that keeps us going. It is the realization that we cannot waste a minute in this unique atoll. Laziness and idleness are alien words here, and we don't have enough hours to dive as much as we would like. The mere thought of meeting the sharks again, or hovering over a coral infinity, triggers our adrenaline.

Tyler Rowe and I camped on Isla Maxima, the small island on the eastern arm of Kingman, last night. We wanted to experience the isolation of an ocean dot made of coral rubble and giant clamshells. The moon rose as the sun set in the opposite corner of the sky. Two large spotted eagle rays hovered over a reef colored with pink coralline algae. A dozen brown boobies glided over the water, up and down, back and forth, as if on an endless aerial rollercoaster.

The Kingman reef ecosystem is a complex living machine composed of many thousands of species, which are linked by relationships of different natures. Some organisms, such as corals, create habitat for others; others, such as sea cucumbers, work as garbage cleaners processing debris. But nothing characterizes better the struggle for existence than the relationship between predator and prey. Predation is a rather unfair relationship in which there is always a winner-and a loser. So engrained is it in our perception of nature, that students of linkages between species in an ecosystem have consistently worked on food webs and often ignored most other kinds of relationships.

Yesterday I wrote in my journal about how easy it is to get accustomed to something extraordinary.

A room warden at the Prado Museum will probably not be as excited at the sight of a masterpiece by Velazquez as a tourist will. Likewise, after 10 days of diving at Kingman we appear to be used to seeing sharks, dozens of large red snappers, and healthy corals on every dive. We have seen between five and 24 sharks on every single dive. It would take years of diving in the Caribbean to see as many sharks–without feeding, of course.

Today we had another calm day in paradise. The first thing I do every morning when I climb the stairs from my stateroom to the galley of the Searcher is to look out. After a soft “good morning” to the few souls sipping their coffee in silence, I step outside. It is bright, and I am obliged to squint. After a few seconds, my sight travels instinctively to the reef crest, hoping for as few breakers as possible. Today is one of those lucky days when the reef crest is difficult to find, and I awake instantly with excitement. We will dive on the fore reef, outside of the coral ring. The fore reef is the section of the atoll with the greatest fish biomass, hence sharks.

We conduct two dives in the morning, at 20 and five meters deep respectively. It takes us about five minutes to travel from the Searcher to La Paloma pass, and about fifteen more minutes to move around the apex of the atoll and reach our sampling site. The crew of the Searcher takes turns taking us diving and tending the boats. Our skipper this morning was Jon Littenberg, the captain of the Searcher.

Jon’s story is, as typical of those people who have dream jobs, serendipitous. He and his family had a smaller boat in Hawaii, and decided to help some local researchers with it. They liked it so much that they decided to purchase a bigger boat and make supporting scientific research a way of life. They purchased the Searcher, which was formerly a private yacht. We are very happy with the former life of the Searcher, because it provides much more comfortable conditions than we scientists are used to.

While we were counting fishes this morning I looked to my side and saw Jon near the bottom, taking photos of large, black pencil sea urchins, whose spines were, not surprisingly, the size of pencils. I was diving with tanks, but Jon was snorkeling. He is a strong free diver, and I have seen him next to us several times before. When I am scuba diving and he is free diving I am jealous, and feel he is closer to the fish than I am.

After the morning dives, Jon told me that “it is good to know that places like Kingman still exist. Most people don’t realize how unique and fragile these places are.”

I could not agree more. In 2005, when I flew back to California after five wonderful days at Kingman, I realized how rare places like Kingman are. My plane was about to land in Los Angeles, and all I could see were lights, millions of lights, embedded in an invisible matrix of concrete. I wondered how much larger than Kingman our cities are. If we dropped Kingman in Los Angeles, we could spend a week driving around and never find it. We have too many big cities, but how many Kingmans do we have?

History books are replete with wild tales of exploration. Magellan and his crew fought unfathomable seas in their first crossing of Cape Horn. Captain Cook sailed ships across the globe, filling in maps with distant islands and atolls, ultimately losing his life in the process. And Shackelton tried time and again to cross Antarctica on foot and, despite never finishing the crossing, returned with stories and photos that have awed generations. The curiosity about the unknown is what draws us in and keeps us all enthralled.

The same curiosity that drove these explorers to push the limits of the known exists in each of us. Here on Kingman we are taking advantage of this rare opportunity to explore as much of this remote atoll as is possible. Many dives are simple, with short runs in our small boats to get to the dive sites. But many are not quite as simple.

Today we rounded the eastern apex of the atoll in a crossing that conjured up stories about Magellan (we named the crossing Kingman’s Cape Horn). We took advantage of the lull in the wind to dive along the northern shore at locations that are frequently pounded by large waves and scoured by fast currents. Along this shore we found unique habitats of spur and groove reefs, complementing the continuous and patch reef habitats that have been common elsewhere.

The winds picked up during the dives, however, and we thumped home taking on 20-30 knot winds. This afternoon we dived inside the lagoon in a back reef environment that on first pass appeared biologically depauperate, but a little patience brought us new rewards. Both the sites on the north shore and in the lagoon were home to species that we had not yet found during this trip. We found new types of communities that are likely serving unique roles in this atoll environment. Our exploration continues, with the goal to fill in a map of Kingman, both in the structure and in the functioning of this living community.

At whatever scale that a person looks, be this in a tour of the globe, a detailing of a coral reef, or a walk through Central Park, we can each be explorers. We will keep up our work here on Kingman, taking advantage of this once-in-a-lifetime opportunity to live inside of an atoll for three weeks. I recommend that each of you take advantage of your local environment and explore. We each have a bit of Shackelton within us.

—Dr. Stuart Sandin

First, a healthy reef is not healthy everywhere. In the same way that a falling giant tree will create a clearing in the jungle and start a competition among younger trees to reach the sky, a coral reef will have patches of death that will become alive in due time.
    This morning we dove at a site near La Paloma pass, the only significant channel connecting the lagoon and the fore reef on the southern side of Kingman. Ten meters below our boat, the bottom was covered with coral rubble. A few hundred meters west or east, the corals are healthy and form a thick forest. But this patch is a reminder that there are greater forces operating in the world, and that even remote reefs cannot escape from them.
    Kingman was impacted by a Pacific-wide warming event in 1997-8, called El Niño. The surface waters became too warm for too long, many corals bleached, and some of these died. Corals died, but they recovered in most of the atoll. Why did they not recover at the site we visited this morning? Probably because this site is immediately west of La Paloma.
    The lagoon breathes with the tides, inhaling clean water from the central Pacific on the flow tide, and exhaling water filled with sediment from the lagoon on the ebb tide. The outgoing water from the lagoon is pushed westwards by the surface waves, which are in turn created by the trade winds, blowing mostly from east to west. This might have inhibited the recovery of the corals to date. However, the good news is that the rubble is scattered with thousands of small corals.
    Replenishment may take a while, but it is on its way. Paraphrasing Inspector Clouseau, everything nature does is carefully planned—or at least until we started to mess things up. Second, unlike what many people believe, sharks have not evolved for 300 million years with the sole mission of devouring every single human that sets a fin in the ocean. I mentioned earlier that sometimes sharks get quite close to us. Today, however, we could not get them close enough.
    The usual protocol consists of us jumping in the water, a dozen sharks coming to check us out, and then losing interest and leaving. They may come back during the dive, or especially when we climb back to the boat; they appear particularly bold at dusk. However, they never made any attempt to check if we taste good.
    This is what a healthy coral reef is supposed to be: abundant predators that have no particular interest in strange creatures with one large eye and two tails, and who produce noisy bubbles. The rest is all fantasy for cheap reality shows that appear to have replaced good natural history.

The goal of our expedition is manifold, but it could be condensed into two main goals. First, we aim at describing a healthy coral atoll in its entirety or, more humbly, within the limits of our expertise and physiological limits. That is, we will survey the reef ecosystem from viruses to sharks, from the shallow giant clam beds in the lagoon to the fore reef 20 meters deep.
    To undertake such an ambitious task we have a four-person fish team, a two-person coral and algal team, and a two-person microbial team. The fish team is composed of Ed DeMartini, Alan Friedlander, Stuart Sandin, and myself. We dive three times a day and identify, count, and estimate the size of all fishes within two meters on either side of 25 meter-long lines, or belt transects. We carry out three such transects per dive, and expect to encounter more than 200 species of reef fishes in our surveys. Using the data collected in the field we will estimate the number of grams of each fish species per Meter Square, or biomass. Fish biomass is the single best indicator of fishing pressure, and since Kingman is unfished and protected, it should have one of the greatest fish biomasses in the tropics.
    Jim Maragos and Jen Smith constitute our coral and algal team. They dive twice in the morning. Jen takes dozens of photos of the bottom using a small digital camera attached to a frame made of PVC pipes - a “quadpod”- that allows her to always photograph the same surface in order to obtain comparable samples. She will then spend hundreds of hours in front of her computer, calculating what percentage of the bottom is covered by different species of algae and corals. Meanwhile, Jim Maragos identifies all coral species in situ, and measures the size of coral colonies, including the smallest ones that are indicative of replenishment of the population. A coral reef is a reef made of coral, thus we expect Kingman to be overwhelmingly composed of live coral, and scarce seaweed.
    The microbial team is composed of Linda Wegley and Mark Hatay. They dive in the morning and collect water samples in hard plastic bottles the size of poster tubes. They will then count the number of microbes that inhabit every milliliter of seawater around the atoll, and determine how fast bacteria reproduce. The rate of bacterial growth is a good indicator of how “clean” the ecosystem is.
    In addition, Christian MacDonald, our diving safety officer, supervises our diving operation and ensures that we conduct our daily activities safely. In other words, he makes sure all of us return to the Searcher every day. That is no small task.
    As I mentioned yesterday, our goal is not conducting scientific studies for the sake of science, but to obtain a rigorous description of a healthy coral atoll so that we can use it as baseline for coral reef conservation.
    Our second aim is to make the public aware of what we find, and to show them why it matters. To achieve this goal we have one of the best underwater photographers in the world, Brian Skerry, who is shooting for a story that will appear in National Geographic magazine. Brian typically takes a boat and an assistant, and goes diving for four or five straight hours. He then comes back to the boat with amazing photos, although he never seems totally happy, and goes back to the same place to make a yet – incredibly - better shot.
    Finally, our young videographer, Tyler Rowe, is shooting with a high-definition video camera in an underwater housing. He will produce short videos for what I call a communication experiment: a scientific expedition seen through the eyes of a teenager. We wish more young people were attracted by natural history, and hope these videos will help recruit some of them.
    The crew of the Searcher is a terrific team that deserves a full daily dispatch...