Galeorhinus
Galeorhinus is a genus of requiem sharks belonging to the family Triakidae. These sharks are commonly known as “school sharks” or “soupfin sharks” due to their schooling behavior and their historical use in shark fin soup. The genus comprises two recognized species: Galeorhinus galeus, the common school shark, and Galeorhinus japonicus, the Japanese school shark.
Characteristics
Galeorhinus sharks are characterized by their slender, fusiform bodies and pointed snouts. They typically grow to a length of 1.5 to 2 meters (5 to 7 feet). Their coloration varies by species, with Galeorhinus galeus having a grayish-brown to olive-brown dorsal surface and a white underside, while Galeorhinus japonicus has a more grayish-blue dorsal coloration.
They possess two dorsal fins, a large anal fin, and a heterocercal caudal fin with a distinctive lower lobe. Their teeth are small and numerous, adapted for tearing and gripping prey.
Environment and Distribution
Galeorhinus sharks are found in temperate waters around the world. Galeorhinus galeus has a wider distribution, occurring in the eastern and western Atlantic Ocean, the Mediterranean Sea, and the Pacific Ocean off the coasts of Australia, New Zealand, and South Africa. Galeorhinus japonicus is restricted to the Northwest Pacific Ocean, off the coasts of Japan, Korea, and China.
They inhabit coastal waters, often near sandy or muddy bottoms, and can be found at depths of up to 300 meters (984 feet). These sharks are primarily found on the continental shelf and upper slope.
Diet and Behavior
Galeorhinus sharks are opportunistic predators that feed on a variety of prey, including fish, squid, crustaceans, and even smaller sharks. They are known for their schooling behavior, often congregating in large groups, especially during spawning season. Their diet varies by age and location, but generally includes a mixture of pelagic and benthic prey.
Conservation Status
Both species of Galeorhinus are considered to be vulnerable or endangered due to overfishing and habitat degradation. The common school shark (Galeorhinus galeus) is listed as "Near Threatened" by the International Union for Conservation of Nature (IUCN).
Their populations have declined significantly in recent years, and there are concerns about their long-term sustainability. Conservation efforts focus on sustainable fishing practices, habitat protection, and public awareness about the importance of these species.
References
For more information about Galeorhinus sharks, please refer to these reliable sources: