Scientists have documented less than 10 per cent of the estimated 2.2 million fish, marine mammals, shellfish, plankton, squid, and jellyfish inhabiting the world’s oceans, CBC reported. The Ocean Census, a global collaboration of scientists and non-profit organizations, warns that unknown marine biodiversity hinders global conservation efforts.
According to CBC, Ocean Census head of science Michelle Taylor stated, "It’s very difficult to protect what you don’t know."
Researchers identified 57 new species during an October expedition off Argentina. Among the discoveries in the Mar del Plata submarine canyon was a sea cucumber with horned appendages nicknamed Loki, alongside a bright red-orange octocoral found nearly 2,000 metres below the surface.
A landmark United Nations biodiversity agreement in 2022 committed to protecting 30 per cent of marine areas by 2030. However, current protections lag behind with just 12 per cent of oceans set to be protected by 2030, compared to 27 per cent of lands, according to CBC.
Exploring steep underwater terrain continues to yield unexpected discoveries in Canadian waters. Claire Goodwin, a research scientist at the Huntsman Marine Science Centre in St. Andrew’s, N.B., surveyed the Saguenay Fjord in Quebec in 2023, where her team found 20 to 30 sponge species.
The expedition discovered carnivorous sponges that trap shrimp with glass, velcro-like appendages to engulf and digest them slowly. Most sponges operate as passive filter feeders, making the carnivorous behavior an unusual find, Goodwin told CBC.
"Which was really exciting," said Goodwin.
Goodwin is currently working with the Innu Nation in Labrador to survey uncharted seabed territory. Meanwhile, Loïc Jacquemot, a postdoctoral researcher at Université du Québec à Rimouski, is surveying Baffin Bay off Nunavut using environmental DNA, or eDNA, which identifies species from skin and tissue shed into water samples.
Rapid ocean warming is altering species distribution and threatening fragile ecosystems.
Cold-water species face shrinking habitats because they cannot migrate further north, while warmer-water species expand their ranges. These shifts disrupt food webs and alter carbon storage mechanisms managed by zooplankton.
Jacquemot explained to CBC that "It’s important for the climate because all these changes impact the way carbon is stored in the ocean,"
The ocean has absorbed 30 per cent of human-generated carbon dioxide and 90 per cent of excess heat from climate change, according to a recent UN report. These marine ecosystems and their ability to store blue carbon are a primary focus at the UN climate summit, COP31, underway in Antalya, Turkey.
Researchers use eDNA to identify marine species from genetic material like skin, poop, and tissues shed into the water. This technique allows scientists to survey biodiversity without directly seeing or catching the organisms.
Only 12 per cent of the world’s oceans are set to be protected by 2030 under a 2022 UN biodiversity agreement. Canada has protected 15.5 per cent of its oceans, according to the Canadian Parks and Wilderness Society.
Most sponges act as passive filter feeders, but carnivorous sponges use glass, velcro-like appendages to trap and slowly digest small crustaceans like shrimp.
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