by Andrea Quattrini, Harvey Mudd College
Kenneth Sulak, U.S. Geological Survey
July 1, 2018
This video, collected during Dive 16 of the expedition, highlights a benthic fish dwelling in a burrow, snatching a large midwater fish with quill worms as onlookers. This remarkable video footage gives us the rare opportunity to document a predation event in the deep sea, while highlighting the trophic links between animals that live in the water column with those that live on the seafloor.
This burrowing fish was hard for scientists to identify at first, as it resembles both an offshore toadfish and a wrymouth. However, freezing the video just before the attack, you can see three of the photophores that we can use to help determine the species of fish. Based on that, we know that it is an Atlantic Midshipman, Porichthys plectrodon. The same species, Atlantic Midshipman, was seen on previous dives, including Dive 14, 15, and 16.
During Dive 16, the specimen was a bit further out of its burrow, such that the photophores under the eye and along the lateral line are clearly visible, allowing for confirmation of identification. These fish are sit-and-wait ambush predators, like anglers and lizardfishes, and have some of the fastest strikes of any fishes. So fast that it takes super slow motion video to actually see what is happening.
The victim for this predator was a water column fish, a barracudina in the family Paralepididae, and it can be identified based on the big eye and long straight jaws with straight gape. It is interesting that this fish appeared damaged before being eaten – mucus coat frayed and a strip of skin dragging along the side of the body.