An underwater camera sends back a sound that makes the whole room quiet during a research trip. This sound can be heard anywhere from the surface to a kilometer below. In late 2018, the CSIRO’s RV Investigator was on an expedition to the Coral Sea Frontier. This has been happening over and over again as taxonomists sort through the things the ship brought back. Scientists say that number will probably go over 200 once the harder-to-classify creatures are fully studied. So far, more than 110 new fish and invertebrate species have been found in the Coral Sea alone.
That’s not a little thing. Nearly a million square kilometers of mostly dark, deep water make up the Coral Sea Marine Park. It is right off the northeastern coast of Australia. In terms of size, it’s one of the world’s biggest marine parks. Not long ago, most of the living things that lived in it, especially below 200 meters, were not known.
CSIRO voyage chief scientist Dr. Will White, who is an expert on sharks, found and named four new species around Australia during a series of taxonomic workshops. These species were a chimaera, two rays, and a deepwater catshark. Taxonomists from museums, universities, and research institutes worked together on these workshops, which were probably the biggest of their kind ever held in the country. They looked at hundreds of specimens by touching them and sequencing their DNA. There are new species of brittlestars, crabs, sea anemones, and sponges every time you look. One of those camera feeds caught video of a sand tiger shark, Odontaspis ferox, which is a deepwater relative of the grey nurse shark and is rarely seen and filmed.
Take a moment to think about that. This wasn’t a trip to a trench in the middle of a faraway ocean that had never been reached before. The Great Barrier Reef, which is next to the Coral Sea, is one of the most studied marine environments in the world. The assumption, which was probably reasonable up until now, was that the waters nearby were pretty well known. That’s not true.
A different book coming out in June tells a similar story from the other side of the continent. After trips in 2021 and 2022, scientists from Museums Victoria, CSIRO, and the Australian Museum identified 149 new species in the water around Christmas Island and Cocos (Keeling) Islands. The scientists looked at 22 seamounts, which are huge underwater mountain ranges, and collected more than 1,000 specimens from depths of up to 5,000 meters. Bathyvermilioides juliebrockae, a new species of annelid worm, was found at that depth. It is one of the deepest new species that the RV Investigator has ever found. Also, they found more than 1,000 shark teeth on the ocean floor. Some of them belonged to species that went extinct between 22 and 33 million years ago. Sitting in the sediment is old ocean history.
As a jellyfish expert, Dr. Claire Rowe was on both the trip and the analysis that followed. She talked about the animals with an honest sense of wonder that is refreshing to hear from a scientist who is deep in their work. “Some of these specimens have been collected down to 5,000 metres below the surface,” she said. “I can’t even run 5ks.” There’s something very interesting about that. People who study the ocean for a living still find it really strange because it is so different from everyday life.
The information is being sent to the Ocean Census Biodiversity Data Platform, an open-access system that lets scientists around the world see in real time any new species that are found. Even though the pipeline seems to be working, it’s still not clear how long it will take to fully process everything that has been collected. Specimens are kept in national museum collections all over Australia so that researchers can come back to them as tools for identification and sequencing get better.
Beyond the number of new species, what makes all of this quietly important is what it shows about the gaps in what we know. If these kinds of discoveries can still be made in waters this close to coastlines that have been studied a lot, then most of the deep ocean is still uncharted. The RV Investigator is a single ship that only works in one part of the world and goes on expeditions every few months or years. It seems like scientists are racing against time, or at least against how quickly the environment is changing in waters that haven’t been fully mapped out yet.
Parks Australia is already working on ways to manage and protect the Coral Sea Marine Park that take these findings into account. That’s the point of all this taxonomy: not just giving things names, but also understanding ecosystems well enough to make decisions that can be defended. At the moment, it’s not clear if the rate of discovery can keep up with the challenges these places face.
