What are Hammerhead Sharks?

About Hammerhead Sharks:

• Named for the unusual and distinctive form of their heads, hammerhead sharks belong to the family Sphyrnidae.
• They are characterized by a flattened hammer- or shovel-shaped head, or ‘cephalofoil’.
  • These distinctive heads serve multiple purposes, including granting the sharks360-degree vision as well as better hunting abilities.
• There are nine species of Hammerhead Sharks, each with varying lengths. 
• The great hammerhead shark is the largest of all hammerhead species, reaching a maximum known length of 20 feet.
• Distribution:
  • They are widely distributed in tropical and temperate marine waters near the coasts and above the continental shelves. 
  • They may migrate seasonally, moving equatorward during the winter and poleward during the summer.
  • o In years with warm El Niño conditions, hammerhead sharks may range many hundreds of kilometres farther than normal.
• Features:
  • The upper sides of these fish are greyish-brown or olive-green, and they have white bellies.
  • They have very impressive triangular, serrated teeth—like the edge of a saw's blade.
  • The hammerhead also has special sensors across its head that helps it scan for food in the ocean. 
  • They are viviparous: they retain fertilized eggs within the body and give birth to live young
  • They can live 20-30 years.
  • They are exothermic animals, meaning that they have no internal way to control their body temperature.
• Hammerhead sharks are one of the most threatened shark families, mainly due to overexploitation, with all species but one (Sphyrna gilberti) being globally listedas Vulnerable, Endangered, or Critically Endangered by the IUCN.

Q1: What is a continental shelf?

A continental shelf is the edge of a continent that lies under the ocean. A continental shelf extends from the coastline of a continent to a drop-off point called the shelf break. From the break, the shelf descends toward the deep ocean floor in what is called the continental slope.

Source: New Species of Hammerhead Shark Discovered