The frilled shark, often described as a living fossil, represents an ancient lineage of deep-sea creatures. Its appearance is distinctly unusual, featuring an elongated, eel-like body that can reach nearly 7 feet in length. The shark’s name comes from its six pairs of gill slits, which possess a distinctive frilly margin, with the front pair extending beneath its throat like a collar. Dwelling in the ocean’s dark depths, this rarely observed animal remains largely mysterious, making its biology, particularly its feeding habits, a subject of ongoing scientific inquiry.
Primary Prey
Information regarding the frilled shark’s diet primarily stems from the analysis of stomach contents from captured specimens. These studies indicate that cephalopods, particularly squid, constitute a significant portion of its diet, often comprising around 60% of stomach contents in some populations. The flexible bodies of squid make them suitable prey.
Beyond cephalopods, the frilled shark also consumes various deep-sea fish. These fish are slower-moving or bottom-dwelling species. Frilled sharks also prey on other sharks, including smaller species and even their own kind, indicating a broad and opportunistic feeding strategy in the nutrient-scarce deep-sea environment.
Hunting Adaptations
The frilled shark possesses unique physical characteristics that enable its predatory lifestyle in the deep sea. Its mouth is armed with numerous, needle-sharp, trident-shaped teeth, arranged in multiple rows. These recurved, inward-curving teeth are effective for grasping and preventing the escape of slippery prey like squid.
Its jaws are remarkably wide and highly distensible, allowing it to swallow prey that can be large, sometimes exceeding half its own body size. Its elongated, eel-like body and flexible spine contribute to its hunting prowess, enabling rapid lunges and contortions to capture food. Scientists hypothesize that the frilled shark functions as an ambush predator, waiting patiently and launching a sudden, snake-like strike to overwhelm unsuspecting targets rather than actively pursuing fast-moving prey.
Deep-Sea Habitat and Diet
The frilled shark’s deep-sea habitat profoundly influences its diet and hunting approach. Food resources in the deep ocean are sparse and scattered, leading to a dietary strategy that involves consuming a wide variety of available prey. Deep-sea creatures, including the frilled shark, typically exhibit low metabolic rates, allowing them to survive on infrequent, large meals.
The frilled shark’s ability to swallow sizeable prey whole aligns with this adaptation, maximizing the energy intake from each capture. While primarily a benthic (bottom-dwelling) species, some observations suggest it may undertake diel vertical migrations, moving higher in the water column at night to follow and feed on migrating squid, adapting its diet to available food.