Finding a meal on the muddy seafloor sometimes requires you to follow your nose. 

The ocean’s surface delivers a feast of organic material to the abyss. Poop, snot, dead plankton, and even larger animal carcasses provide a tasty treat for deep-sea scavengers. On the abyssal seafloor, it is mud as far as the eye can see, and food can seem scarce unless you know where to look. 

The giant cusk-eel (Spectrunculus grandis) is one of the largest bony fishes in the deep abyss. Sometimes referred to as “swimming noses,” these fish rely on their large olfactory organs to sniff out their next meal. They are not picky eaters and will dine on a variety of bottom-dwelling invertebrates like crustaceans, worms, and sea stars, and animal carcasses.

We frequently encounter Spectrunculus at our deep-sea research sites offshore of California. Near Davidson Seamount, they search for invertebrates nestled among the coral gardens. At whale falls we have monitored in Monterey Canyon, they feast on decomposing whale blubber. And they fill their bellies with dead octopus at the famous Octopus Garden. 

Giant cusk-eels are common worldwide and call the abyssal zone—the sprawling, flat deep ocean floor—their home. Despite covering more than 50 percent of the Earth’s surface, the deep seafloor is one of the least studied habitats on this planet due to the challenges of exploring this vast environment miles underwater.

Spectrunculus is just one of the many fascinating animals that thrive on the abyssal seafloor. As society looks to the deep sea for mining rare minerals such as cobalt and nickel, understanding the importance of this spectacular species and other abyssal animals has become especially urgent. Our research is revealing how human actions will affect deep-sea communities. We are providing the information policymakers need to guide their decision-making about the ocean, its inhabitants, and its resources.

Next time you think about our ocean, remember these charming and curious deep-sea neighbors roaming the seafloor, sniffing out their next meal. The deep sea is closer than you think. Our choices and actions on land ripple to the ocean’s deepest depths—we need to do our part to protect deep-sea animals and environments from threats like climate change, overfishing, mining, and pollution.