Researchers indicate that the lack of knowledge about oceanic life is impeding conservation efforts. Consequently, numerous scientists are engaged in the urgent task of discovering and cataloging the myriad species inhabiting marine ecosystems that are frequently challenging for humans to explore.
Ocean Census, a worldwide partnership of scientists and non-profit entities, suggests that less than 10 percent of the approximately 2.2 million species, including fish, marine mammals, shellfish, plankton, squid, jellyfish, and others, have been recorded.
“It’s extremely challenging to safeguard what you are unaware of,” stated Michelle Taylor, the science lead at Ocean Census.
Among the 57 newly identified species revealed in October from a recent Ocean Census expedition off the coast of Argentina, is a horned sea cucumber nicknamed Loki and a vibrant red-orange coral characterized by slender branching fans.
This newly identified sea cucumber species, named Loki due to its distinctive horned appendages reminiscent of the Norse god, was discovered in the Mar del Plata submarine canyon near Argentina. (ROV SuBastian/Schmidt Ocean Institute)
A striking bright red-orange octocoral was photographed nearly 2,000 meters below the ocean’s surface in Argentina’s Mar del Plata canyon. (ROV SuBastian/Schmidt Ocean Institute)
A significant UN biodiversity treaty established in 2022 committed to safeguarding 30 percent of the planet’s land, water, and marine territories by 2030, yet has been falling short on ocean conservation, with only 12 percent of oceans (in contrast to 27 percent of land) expected to be protected by 2030.
As per the Canadian Parks and Wilderness Society (CPAWS), Canada has successfully protected 15.5 percent of its marine areas.
Research scientist Claire Goodwin from Huntsman Marine Science Centre in St. Andrew’s, N.B., emphasized the importance of conserving regions with rich biodiversity.
“However, if you are not surveying some of your marine species and lack knowledge of what resides there, you cannot identify which areas are biodiverse.”
A cone jelly was captured by the remotely operated vehicle SuBastian off the coast of Argentina. (ROV SuBastian/Schmidt Ocean Institute)
Meat-eating sponges that provide habitat
The challenge lies in the fact that numerous regions in Canada remain unexplored. Goodwin participated in an expedition in the Saguenay Fjord in Quebec in 2023.
On the steep cliffs, where only a single sponge species had been documented previously, her team unearthed 20 to 30 sponge species, including several that were previously unknown to science.
Carnivorous sponges were discovered in Quebec’s Saguenay Fjord in 2023. (Claire Goodwin/HMSC)
Among these were carnivorous sponges that capture shrimp using glass, velcro-like structures to engulf and digest them slowly, which Goodwin described as “thrilling,” considering that most sponges are filter feeders.
Goodwin highlighted the vital roles sponges play in ecosystems—serving as food for sea stars, habitats for certain worms, and spawning grounds for some fish. In Canadian waters, sponges can grow to half the height of an adult human.
Claire Goodwin collects sponges in the Bay of Fundy off New Brunswick’s coast. (Torben Brydges/Fisheries and Oceans Canada)
The sea slug Dendronotus yrjargul was documented in a recent expedition led by the Innu Nation. This marked the first discovery of the species off Canada’s coast. (Claire Goodwin/HMSC/Innu Nation)
Currently, Goodwin is collaborating with the Innu Nation in Labrador to investigate unexplored waters within their region. “We genuinely have no idea what the seabed will be like, let alone the types of organisms that may inhabit it.”
Effects of climate change and potential remedies
There is an urgent need to uncover this information as the ocean rapidly warms, and climate change alters species distributions.
Goodwin notes that some species have vanished entirely from areas where they were previously abundant. For instance, she mentions basket stars, which are fascinating sea stars with branching arms that were once prevalent around St. Andrew’s but have not been spotted there since the rapid warming experienced around 2016.
A basket star, Gorgonocephalus arcticus, is pictured in the Saguenay Fjord. This species, once common in the Bay of Fundy, seems to have disappeared due to climate change. (Claire Goodwin/HMSC)
Loïc Jacquemot, a postdoctoral researcher at Université du Québec à Rimouski, remarked that in numerous locations, we lack a sufficient baseline to assess changes.
He is currently conducting surveys in Baffin Bay off Nunavut’s coast utilizing a method known as eDNA analysis, which detects species through DNA shed into the water from organisms’ skin, feces, and other tissues. This approach allows for surveying organisms without the need to see or capture them—only a water sample is required.
Loïc Jacquemot collects water samples for eDNA in the coastal fjords of British Columbia. (Submitted by Loïc Jacquemot)
He mentioned that species acclimated to colder waters are anticipated to migrate into increasingly restricted areas “since, naturally, they cannot continue moving north,” while species that favor warmer waters might broaden their distribution.
This shift could significantly affect the food chain—impacting fish and shellfish consumed by humans—and the manner in which carbon is transferred throughout the ocean by zooplankton species that daily migrate between the depths and the water’s surface.
“This is crucial for the climate because all these transformations affect the ocean’s carbon storage capabilities,” Jacquemot stated.
This tiny copepod is among the 20 new species identified by the Ocean Census in October. These organisms are part of the zooplankton that transfer carbon between the ocean’s surface and its depths. (The Nippon Foundation-Nekton Ocean Census/Schmidt Ocean Institute)
Photosynthetic algae known as diatoms from Greenland’s fjords. Diatoms play a vital role in capturing carbon dioxide in the oceans. (Submitted by Loïc Jacquemot)
The carbon stored by the ocean and its organisms is referred to as blue carbon. To date, it accounts for 30 percent of the carbon dioxide produced by humans, along with 90 percent of the additional heat trapped due to climate change, according to a recent UN report, which cautioned that the ocean’s capacity to absorb more CO2 and heat is diminishing.
Simultaneously, coral reefs, recognized as biodiversity hotspots capable of sequestering substantial amounts of carbon, are among the ecosystems most at risk from climate change.
The role of the ocean and its life forms in climate change is a key focus at this year’s UN climate summit, COP31, currently taking place in Antalya, Turkey. Ensuring the protection of marine ecosystems and “unlocking blue carbon for climate resilience” is one of the ten priorities on the meeting’s “action agenda.”
At COP31 this week, former U.S. Secretary of State John Kerry and representatives from island nations advocated for a strong emphasis on oceans in next year’s global “stocktake” of climate initiatives, with support from the European Union and African nations.
This grenadier fish was seen with parasitic copepods attached to its head during a 2025 Ocean Census expedition off Montagu Island near Antarctica. (ROV SuBastian/Schmidt Ocean Institute)
This marine worm, Harmothoe imbricata, was discovered off Canada’s Atlantic coast. (Christy Carr/HMSC)
For the ‘biogeochemical functioning of our planet’
Taylor from Ocean Census emphasized the significance of marine ecosystems for humanity—not only for food and medicine production but also on a broader scale. “It’s integral to the biogeochemical functioning of our planet. We are heavily reliant on it, whether we are aware of it or not.”
Taylor, Goodwin, and Jacquemot aspire that by showcasing the remarkable variety of life in the ocean, they can foster greater appreciation for the need to preserve it.
“When we present images and videos of the underwater world, people’s astonishment at the diversity we have down there is always evident,” Goodwin remarked.
Michelle Taylor, the science leader for Ocean Census, reviews footage from the cameras on the ROV SuBastian during a mission to document deep-sea species. (Paul Satchell)
Taylor describes the underwater inhabitants as an astonishing array of “strange-looking creatures,” noting that for some, “you would hardly believe they belong to this planet.”
She expresses significant concern about the future of coral reefs but maintains that “we must adopt the mindset that solutions are available.” In the meantime, she underscored the necessity to identify as many species as possible to grasp the diversity present on our planet before it is lost.
This article is part of a series highlighting the efforts of scientists investigating vanishing species that may not have received much attention. It offers an opportunity to learn about these species, their influence on our lives, and discover what actions can be taken to ensure their survival.