Blue Whale in Costa Rica
October 30th, 2012
It has long been noted that Costa Rica is ripe with hammerhead sharks all over its waters. The hammerhead sharks belong to the shark family Sphyrnidae. They have been very aptly named for the distinctive and highly unique shape of their heads which is related to their species alone. These very different sharks have a flat and elongated head which extends to either side, outwards from their body. It highly resembles a hammer which in scientific terms is called “cephalofoil”. Hammerhead sharks usually prefer warmer waters which is why they inhabit the coast and waters of Costa Rica and the Pacific Ocean. An interesting fact about this specie is that they usually travel in a school which is highly unusual for most types of sharks. But these schools form only in the day; by night each hammerhead shark hunts in an individual manner. Colombia and islands near it have a lot of hammerhead sharks living in the area. Cocos Island near Costa Rica also possesses many schools of hammerhead sharks. Hammerhead sharks can grow from 3 feet to almost 20 feet. Young hammerheads weigh 3 kg while fully grown sharks may weigh up to 580 kg. Maybe to balance out their large and flat heads, the bodies of the hammerhead sharks are sleek and slender. They can swim with surprising speed in the ocean, maneuvering their bodies to move in the water. The hammerhead sharks have a silvery gray body with a slight greenish overcast which mixes the two colors. The underside of their body is white in color which is characteristic of most sharks in the Pacific Ocean. The advantage of having a body of this color is that the sharks can blend in with the bottom of the ocean. This allows them to sneak up on their pray and take them by surprise. In the open water, away from the bottom the hammerhead sharks may not have this advantage because of their large bodies and the distinctive shape of their heads. This can give a warning to potential pray in the area and scare them off.
Relationship with Humans
There are several types of hammerheads: scalloped hammerhead, great hammerhead, scoophead, smalleye hammerhead, smooth hammerhead, etc. Out of these well known types, the scalloped, smooth and great hammerheads are especially dangerous to humans. They pose great threats to the human population, especially scuba divers and even some snorkelers. Costa Rica and surrounding lands have been acclaimed for successfully protecting most species of the hammerhead sharks but this may come at great cost to the humans inhabiting the area. These are endangered species but Costa Rica and the people in charge of the Pacific Ocean are working very hard to preserve the different types of the hammerhead sharks. The threatening relationship with human also exists because shark fins are considered a delicacy in a lot of countries in the world. This is one of the reasons why the sharks and humans hunt each other and are a threatening presence for one another. A technique these sharks have to avoid predators is to swim in relatively shallow waters where they can easily counter threats from humans and avoid most of the other predators in the sea.
Video for Hammerhead Sharks
References
Sepkoski, Jack (2002). “A compendium of fossil marine animal genera (Chondrichthyes entry)”. Bulletins of American Paleontology 364: 560
“Record Hammerhead Pregnant With 55 Pups”. Discovery News. Associated Press. July 1, 2006.