Scientists have discovered nine new species of deep-sea sponges off the coast of Alaska, shedding light on the region’s largely unexplored marine biodiversity. The National Oceanic and Atmospheric Administration (NOAA) announced the discovery, noting that the species were found in the Gulf of Alaska and the Aleutian Islands. This brings the total number of known sponge species in Alaska to 232. The specimens were collected during NOAA Fisheries’ annual bottom-trawl surveys, which are used to monitor fish and shellfish populations. Researchers analyzed samples collected as far back as 2012, describing the new species in two recent scientific papers. Sponges are among the oldest multicellular animals on Earth, with a history stretching back over 600 million years. Often called "living water pumps," they filter seawater and play a key role in creating habitats on the seafloor, even though they lack brains or complex organs. “Sponges are ecologically important,” said Sean Rooney, a NOAA fisheries biologist and co-author of the studies. “They provide complex structures on the seafloor that serve as habitats and refuges for commercially important fish and crabs,” he explained. Rooney also noted that each new species discovery opens up new possibilities for understanding the deep sea, which is difficult to access, especially in rocky areas that are not easily surveyed by traditional methods. Unlike many marine animals, which can be identified by visible traits like body shape and fins, sponges are more challenging to distinguish. Their lack of complex organs and external features means scientists often rely on their microscopic skeletons and genetic material for identification. “DNA barcodes offer a quick genetic reference,” said Meredith Everett, a biologist at NOAA’s Northwest Fisheries Science Center. “However, sponge DNA can be tricky to analyze because they filter feed, and their tissues may contain foreign DNA and substances that can interfere with testing. Despite these challenges, we have developed several new barcodes for Alaskan sponge species,” she added. Dense sponge communities are considered essential fish habitat by NOAA because they provide shelter that supports the survival, growth, and recovery of fish populations. Sponges also produce chemicals to defend themselves against predators and competitors, and some of these compounds have shown potential for use in cancer treatments. However, Alaska’s deep-sea sponge communities face growing threats from proposals to expand deep-sea mining for minerals like nickel and copper, which are used in military and technological applications. Environmental groups oppose these proposals, warning that such activities could harm fragile seafloor ecosystems, especially as the climate crisis worsens. Cooper Freeman, Alaska director of the Center for Biological Diversity, emphasized the importance of these sponge communities: “Alaska’s sponge gardens are vital for a healthy ocean, providing shelter and serving as nurseries for various fish and crabs. Bottom trawling is highly damaging and unsustainable because it destroys the habitats that support future generations. Adding seafloor mining to the mix is even more harmful, scraping up and devastating life on the ocean floor. Instead of protecting these irreplaceable ecosystems to support Alaskan coastal communities and wildlife, the Trump administration is promoting extractive activities for short-term profit,” he said. The administration has also proposed deep-sea mining in other Pacific regions, including around the Northern Mariana Islands and Guam, a plan that has drawn strong opposition from local communities.