SCALLOPED HAMMERHEAD SHARKS
Certain times of the year Scalloped Hammerhead Sharks (Sphyrna lewini) can be found schooling in the Sea of Cortez in huge numbers. Scalloped hammerheads are known to form very large schools, sometimes containing hundreds.
While we occasionally spot Scalloped Hammerhead Sharks locally and “Across the Bay” the most reliable places to encounter these animals are the Gordo Banks seamount and the El Bajo seamount which we dive on our La Paz trips.
MORE ABOUT SCALLOPED HAMMERHEADS
The scalloped hammerhead is a coastal pelagic species, it occurs over continental and insular shelves and in nearby deeper water. It is found in warm temperate and tropical waters, worldwide from 46° north to 36° south. It can be found down to depths of over 500 metres (1,600 ft) but is most often found above 25 metres (82 ft). During the day they are more often found close to shore and at night they hunt further offshore. Adults occur alone, in pairs or in small schools while young sharks occur in larger schools.
This shark is often seen during the day in big schools, sometimes numbering hundreds. This is most likely because it is easier for the scalloped hammerhead shark to obtain food in a group than alone. This behavior allows for them to catch larger and trickier prey, as commonly seen. The younger the sharks, the closer to the surface they tend to be, while the adults are found much deeper in the ocean. They are not considered dangerous and are normally not aggressive towards humans.
Scalloped hammerhead sharks have a homing behavior in order to navigate in the ocean. They move in the night and use the environment as a map, similar to a human reading a topographical map. By experimentation in tagging these sharks, one could test for any guidance in a shark’s movement. These sharks utilize a point to point type of school swimming, and do not favor going too deep where temperature changes hitchhike with current speed and directional change.
The scalloped hammerhead utilizes deep-water to survive as safety and feeding. Although they have high metabolic rates, they have a tendency to be sedentary and allow currents to carry them as they swim. As a result, this causes the scalloped hammerhead to be selective where they swim and the depth at which they tend to stay at. The scalloped hammerhead has a tendency to eat cephalopods.