Researchers at the Monterey Bay Aquarium Research Institute captured 4K footage of a rare barreleye fish swimming about 600 meters beneath the Pacific Ocean.
Research specialist Shannon Johnson spotted the animal during an expedition as the institute’s remotely operated vehicle, Doc Ricketts, was returning to the surface, according to Albayan. The team was operating from the research vessel David Packard when the encounter occurred approximately 90 kilometers from shore.
The institute’s crew spent 20 minutes observing the animal, scientifically known as Macropinna microstoma, using the vehicle’s 4K camera system. The species features a transparent dome-like shield over its head, which houses large tubular eyes that rotate to track prey in the twilight zone of the ocean where sunlight barely reaches.
Steven Haddock, senior scientist at the institute, described the fish as an example of the capacity of marine life to develop extraordinary adaptations. The organization has conducted approximately 7,000 robotic vehicle dives and amassed over 41,000 hours of deep-sea video footage across its decades of oceanic exploration.
The transparent dome protects the animal’s eyes while it hunts for small crustaceans, particularly when foraging near the stinging tentacles of siphonophores. Large fins allow the fish to hover motionless in the water column while scanning for the silhouettes of prey swimming overhead.
Scientists are also studying pigments inside the lenses of the fish’s eyes, noting similarities to the green pigments found in strawberry squid. The biological team explores how these sophisticated visual systems function in dim environments, investigating the evolutionary competition between bioluminescent camouflage and advanced sight.
During the dive, operators tested varying lighting levels to illuminate the internal structure of the fish’s head and recorded three-dimensional virtual reality footage alongside standard 4K video. The institute noted that this marks the eleventh time researchers have successfully documented the rare species during their deep-sea operations.
The research team left the fish in its natural habitat rather than collecting it as a specimen, ensuring the encounter serves as a reference for ongoing studies into the visual adaptations of midwater marine life.