Table of Contents
Introduction …………………… pg 3-4
Biology of the species ………….pg 4-5
Ecology of the species ………… pg 5-6
SocioCultural values ………….. pg 6-7
Economic Importance ………… pg 7-8
Conservation ……………………pg 8-9
Index …………………………...pg 10-11
Life on earth is greatly influenced by oceanic habitat. All species are directly and indirectly impacted by the choices made by today’s existing generations. Often times humans outweigh anthropometric value from intrinsic value of habitats they’re not familiar with or exposed to every day. Human decision making functions in a way that focuses on determining costs and benefits of a particular situation, which often leads to the perception of natural resources being seen as available resources solely there to benefit humans. When aesthetic values are neglected, species readily become endangered or extinct and natural ecosystems depleted. Species diversity can be defined as a measure of diversity within an ecological community that considers species richness and evenness of species abundance. Over 80% of life on earth lives in the ocean. Large oceanic beings have experienced a horrific decrease in population over the past century due to majority of the world’s societies living by a ‘Frontier World View’ mentality. Recent human exploitation of Elasmobranchii in particular has had an even greater impact globally than majority of society is aware of. Elasmobranchii refers to the subclass of cartilaginous fishes including sharks, rays, and Chimaera. Although each are negatively affected by human influence, I plan on focusing specifically on factors detrimentally affecting sharks throughout this essay, specifically Hammerhead sharks belonging to the family Sphyrnidae. A study conducted by Dalhousie University found that the species has experienced a significant global population decrease of over 99% from 1970-2005 (Myers et al., 2008). An estimated 26-73 millions sharks per year are killed and used for various purposes, one being the major industry of shark finning. The species is rapidly declining and without extreme, immediate resolution, an apex predator imperative to oceanic stability will be irretrievable for future generations. This occurrence will have a negative snowball effect on every other species on earth, as sharks are a critical controlling agent (Baum & Myers, 2004). This paper will review the basic biology of Hammerhead sharks, their ecology, sociocultural values, economic importance, and methods of conservation to preserve this exceptional species that is fundamental to the future of both oceanic and terrestrial life.
Biology of the species
Sharks have lived on earth for over 150,000,000 years, even before the dinosaurs. They are the first invertebrate with jaws and have survived five major extinctions. Hammerhead sharks can be individualized into nine different species and separated into two different families; Sphyrnidae and Eusphyra (consisting of one specie) (Abercrombie et. al, 2005). They can be found in continental shelves and along coastal lines of warmer climate areas (Stevens and Lyle, 1989). Hammerheads tend to be slightly more slender than other shark species and are grey in colour. They are a carnivorous species with a diet mainly consists of fish, squid, octopuses, and crustaceans. Schools of sharks are predominantly found in southern and eastern Africa, Hawaii, Coco’s island off Costa Rica, and Malpelo island off Colombia (Baum & Myers, 2004). In general, sharks are mainly solitary but Hammerheads often come together at a few sea pinnacles to mate and socialize with others. Schools are mostly made up of females who can grow up to 12 feet in length. Schools generally break up at nighttime to descend to deeper water to feed (Klimley et. al, 2006). Hammerhead sharks are extremely unique individuals as they have two additional senses...