Editor’s Note: “The Richest Reef” follows members of a scientific dive team as they attempt to pinpoint the center of the most biologically diverse marine ecosystem in the world. Long considered our planet’s most species-rich piece of ocean real estate, the Western Pacific’s “Coral Triangle” is a continent-sized patchwork of habitats, populations, and communities. Expedition scientists are trying to identify exactly which section of this rich mosaic is most diverse, but their effort carries with it far more meaning than a simple dot on a map would suggest. Along the way, they’ll discover dozens of new species, visit dive sites and depths no one has seen before, and gain a better understanding of the factors that promote biodiversity and the role these species-rich areas play in sustaining healthy ecosystems. See below for a list of all posts in the series.

Throughout this seven-week expedition, nearly 50 team members from the U.S. and the Philippines have explored the biological richness of the most diverse marine ecosystem on the planet. They sampled mangrove thickets and eelgrass shallows. They examined ocean bottoms covered by little more than sand and rubble, and reefs crowded with multicolored corals. They ventured to depths beyond 400 feet, where light scarcely penetrates and where bizarre, resourceful creatures find a way to make a living despite the limitations. And now, the expedition has come to a close.

Late last week, several members of the team took a break from analyzing and processing their recent discoveries, and planning upcoming research trips, to chat with Scientific American’s Blogs Editor, Curtis Brainard, about their perspectives on this year’s expedition, and what comes next. The live event was part of the Google Science Fair’s Hangout On Air series and featured Terry Gosliner and Luiz Rocha, two of the expedition’s scientific leads, Elliott Jessup, the head of the California Academy of Science’s diving program, and Chrissy Piotrowski, one of the Academy’s collection managers charged with making sense of the specimens and data that have come back from the field. If you missed the live event, you can check out the recorded version (embedded above) via Google Science Fair’s YouTube channel.

A spectacular new species of nudibranch discovered in the Verde Island Passage. (Photo by Terry Gosliner)

As you know if you’ve followed this series, what the scientists discovered in the wide variety of habitats they explored was nothing short of spectacular. An overwhelming abundance of organisms and layered diversity were recurring themes on each and every dive. Novelty, though, is what seems to interest people most. A question the scientists get a lot at the end of an endeavor like this one is, “How many new species did you find?”

Benthic ctenophores (comb jellies) collected from the twilight zone near Anilao. (Photo by Bart Shepherd)

As simple as it might sound, this can be a difficult question to answer depending on the taxonomic group one studies. For example, Gosliner and Rocha tend to know right away when they have a new species of nudibranch or fish on their hands. In contrast, a new algae, or tunicate, or bristleworm might require months of careful study to distinguish it from other known species.

So here’s what we know just a few weeks since the field lab in Puerto Galera was packed up and returned to its open-air restaurant status: During the nearly 1,200 scientific dives conducted on this expedition, the team discovered approximately 100 new species—a number that may increase significantly as specimen analysis deepens and intensifies. Of the 15 live fish that were collected from twilight zone depths and brought up via portable decompression chambers, every one survived and made it safely to the Academy’s Steinhart Aquarium in San Francisco, where they’re waiting to go on exhibit in a new twilight zone exhibition planned for summer 2016. So did a small assortment of strange and colorful benthic ctenophores that have become unlikely favorites of several of the aquarium biologists.

A twilight zone diver and two support divers decompressing off the coast of Verde Island. (Photo by Bart Shepherd)

All told, the research team collected some 18,000 individual scientific specimens, which sounds like an awful lot. But, as I wrote in the previous post, those collections, which include many organisms you can hardly see without a microscope, don’t add up to much in the way of volume or weight. And the number itself is tiny in comparison to the tremendous scientific value these specimens will provide for decades to come—and the impact that our knowledge and understanding of these plants and animals might have on efforts to protect the richest of reefs and the habitats that support them.

If you watched the hangout referenced above, you caught a brief glimpse of just how passionate these scientists are about the work they do, and you have a sense of what an eye-opening experience it was for me to follow them into the field and underwater to see them in action and learn why this type of research matters. While every member of the team was happy to call it a day and travel home at the end of a long, exhausting expedition, they will all tell you that there is much left to be done to understand and protect this extraordinary place, and that they can’t wait to come back and continue exploring Earth’s richest reef.

Other posts in this series:

The Richest Reef: Exploring the Most Diverse Marine Ecosystem on Earth

The Richest Reef: No Such Thing as Packing Light

The Richest Reef: Life in Layers

The Richest Reef: A Symbiotic Society

The Richest Reef: A Bagful of New Species

The Richest Reef: Deep Diving into the Twilight Zone

The Richest Reef: Where Have All the Predators Gone?

The Richest Reef: To Collect or Not to Collect?