Hammerhead Shark

Description

The Hammerhead shark is the most unique shark in the ocean. It’s uniquely shaped head makes it a one of a kind for any angler. The hammerhead sharks are a group of sharks in the family “Sphyrnidae,” named after its unusual and distinctive structure of their heads, which are flattened and laterally extended into a shape of a “hammer” called a “cephalofoil.”

All Hammerhead shark species belong to the order of Carcharhiniformes, meaning they are ground sharks with one anal fin and two dorsal fins. A spiral shape intestinal valve means that the food will pass through the intestines at a very slow pace, making it impossible for Hammerhead sharks to eat often. Their growth rate is therefore also very slow. They save energy by not swimming around a lot. The liver of a Hammerhead shark is filled with oil that has a lower density than water. This provides enough buoyancy for the Hammerhead to graciously float in the water rather than swim while scanning the bottom floor for their next meal.

The Head

The unusual and oddly shaped head of the Hammerhead shark has given raise to a lot of speculation. Two main theories regarding its development continue to develop. Some scientists believe that the shape evolved gradually over numerous generations, while others suggest that it was a sudden mutation that rapidly proved to be an advantage. The entire head is equipped with sensors, and might be hammer-shaped in order to provide a larger area for the sensors. This larger sensor area would give the Hammerhead shark an advantage when scanning for food.

Habitat

They are found all over the globe in warm tropical and subtropical waters along continental shelves and coastlines. The sharks are commonly seen in the upper part of the so called mesopelagic zone; the drop-off adjacent to the continental shelf. They dive down to about 260 ft. (80 meters).

The Great Hammerhead shark migrates to cooler waters during the summer season. They are capable predators and eat primarily fish, rays, crustaceans, cephalopods but also other sharks. They are particularly found of rays and will use its “hammer” to hold the ray down while slowly eating away on the wings bite by bite.

Hammerheads can sometimes form schools that contain up to 500 individuals, which is very unusual for sharks. They only school during the day and always spend the nights separated from each other. There seems to be an established order of dominance in every school, where the “rank” of each individual shark is determined by size, age and sex. We still do not know why they choose to live in schools during the day.