The saw jaw shark, belonging to the order Pristiophoriformes, is a unique inhabitant of the deep ocean. These elusive creatures are distinguished by an elongated snout resembling a saw, which they use for various purposes. Found across the world’s oceans, they represent a specialized adaptation among sharks. Their deep-sea dwelling nature means they are not often encountered by humans.
Identifying a Saw Jaw Shark
Saw jaw sharks have a distinctive physical appearance, identified by their flattened, blade-like rostrum, or “saw.” This saw is lined with sharp, alternating teeth along its edges and has a pair of sensitive barbels located halfway down its length. These barbels function as sensory organs, helping the shark detect prey in low-light environments through electroreception and touch. The teeth on the saw are replaceable, unlike those of sawfish.
Saw jaw sharks are slender-bodied and range in size from approximately 1 to 1.5 meters (3 to 5 feet) in length. Their coloration is muted, blending with deep-sea surroundings. It is important to distinguish saw jaw sharks from sawfish (family Pristidae), which, despite having similar saw-like snouts, are a type of ray, not true sharks. A key difference lies in their gill slits: saw jaw sharks have their gill slits on the sides of their body, behind their eyes, similar to other sharks, while sawfish have their gill slits on their ventral (underneath) surface, near their mouth. Sawfish are also much larger, with some species reaching up to 7 meters (23 feet), and their saw has fewer, wider teeth with a rounded tip, contrasting with the saw shark’s pointed tip and needle-like teeth.
Life in the Ocean
Saw jaw sharks inhabit deep-water environments, found on continental shelves and slopes, at depths ranging from about 40 to over 1,000 meters (approximately 130 to 3,300 feet). They are benthic mesopredators, meaning they primarily live and hunt near the ocean floor. Their diet largely consists of small bottom-dwelling organisms such as crustaceans, squid, and small fish.
The saw-like snout is an active tool for hunting. Saw jaw sharks use their rostrum to stun or slash prey by swinging it from side to side. They also rake their saw through the seabed to uncover hidden prey buried in the sediment. This specialized hunting method allows them to forage in their deep-sea habitat. Saw jaw sharks are ovoviviparous, meaning their eggs hatch inside the mother’s body, and live young are born.
Conservation and Human Interaction
Due to their deep-sea habitat, saw jaw sharks are elusive and less studied than many other shark species. This lack of comprehensive data makes assessing their precise conservation status challenging for some species. The primary threat they face is bycatch, where they are unintentionally caught in deep-sea fishing gear such as trawls and gillnets. This accidental capture can significantly impact their populations, especially given their specific habitat preferences.
The International Union for Conservation of Nature (IUCN) Red List classifies various saw jaw shark species with different statuses; some are listed as “Least Concern,” while others are designated as “Data Deficient” or “Near Threatened.” The “Data Deficient” classification highlights the need for more research to fully understand their populations and the threats they face. Given their small size and deep-water dwelling habits, saw jaw sharks pose no known threat to humans.