Towering above the seafloor, Sur Ridge deflects ocean currents, concentrating food and nutrients and creating a hotspot for life. Many fishes and invertebrates live on Sur Ridge’s rocky slopes and in the waters above its crests. MBARI researchers and our colleagues from the Monterey Bay National Marine Sanctuary have documented more than 260 different species at Sur Ridge.

Diving beneath the ocean’s surface reveals an astonishing array of animals thriving in the waters above Sur Ridge. Delicate jellies, curious cephalopods, and toothsome fishes thrive in the midwater—the open expanse of water between the surface and the rocky slopes of Sur Ridge.

Descend further and discover an abundance of magnificent life on the ridge itself. Neon yellow Picasso sponges (Staurocalyptus sp.) and intricately branched bubblegum corals (Paragorgia arborea) anchor to the ragged rock. A hungry rosy tritonia nudibranch (Tritonia tetraquetra) slowly creeps up a coral’s towering skeleton to feast on its feathery polyps. A scarlet Oregon king crab (Paralomis multispina) traverses the terrain scavenging for food. A mother warty deep-sea octopus (Graneledone boreopacifica) clings tight to the rocks as she broods her eggs.

Predators prowl just above the seafloor, taking advantage of the thriving community sheltered among the corals to find their next meal. A longnose catshark (Apristurus kampae) uses electrosensors in its elongated snout to sense the movements of small crustaceans. A Pacific grenadier (Coryphaenoides acrolepis) sniffs out food hidden in craggy crevices. A California slickhead (Alepocephalus tenebrosus) hovers in the currents just above the seafloor and nibbles on tiny crustaceans drifting by.


Bessho-Uehara, M., W. R. Francis, and S. Haddock. 2020. Biochemical characterization of diverse deep-sea anthozoan bioluminescence systems. Marine Biology, 167: 1–19.

Martini, S., L. Kuhnz, J. Mallefet, and S.H.D. Haddock. 2019. Distribution and quantification of bioluminescence as an ecological trait in the deep sea benthos. Scientific Reports, 9(14654).