Pelagic Shark Evolution

Sharks have been in our oceans for almost 450 million years. Those millions of years of evolution have allowed many different shark species to develop abilities, and to become perfect predators.

Overfishing is a death sentence to the world’s oceans. As technology continues to improve a great deal of fish can be caught quicker; but at what cost? The effects of overfishing can lead to the extinction of not just the animals being fished, but also the predators that rely on fish to eat. Ninety percent of the ocean’s largest animals have been wiped out due to overfishing (“Overfishing- A Global Disaster”, 2011). National Geographic cites the academic journal Science (2006) that predicts by 2048, all fisheries will collapse due to lack of ocean wildlife. Fish are not the only animal caught in the nets used by fishing vessels. Often animals such as dolphins, sharks, turtles, and seabirds are

Every Jaws fan knows the shark gets it in the end. What they do not know is that too many sharks have gotten it; and that has caused a rapid decline in the shark population over the past thirty years. Since the 1970's, sharks of the Atlantic and Gulf of Mexico shores have declined eighty-five percent. Sharks are vital animal to our world's ecosystem, and if the decline is not controlled; we could be facing devastating problems in years to come. Information has been obtained from two books: The Shark Almanac by Thomas B. Allen and Sharks, An Introduction for the Amateur Naturalist by Sanford A. Moss. Sources also include a number of online references, among them BBC News, ENS News, The New York Times, and two online scientific

Shark finning is the process of cutting off the fins of a shark and discarding the body at sea (“Stop Shark Finning”, 2009). People catch sharks for its fins, meat, oil, skin and so on. Sharks fins are most commonly used in Asian cooking which is shark fin soup. According to Maddalena, Sommeran and Leander (2007), people have been demanding for shark fins dramatically recently, it is unclear how many sharks are caught annually but some of the conservationists estimate the number to be upwards of 100 million. Besides, shark conservationists are aware about the consequences of the high demand of shark fins, they advocate people to stop killing sharks and eating shark fins. Practice of shark finning is causing imbalance marine ecosystems and it

Arising over 350 million years ago, the shark species has been labeled as a human devourer. Now, with the increase in human population, the demand for shark meat, fins, and cartilage are at an all time high; therefore, the existence of the shark is becoming a concern (Budker 1971). Individuals are conditioned to think of sharks as a negative aspect to the environment, which is prolonging the effort to save shark species from becoming extinct. With that in mind, some private as well as national organizations have accepted the challenge of educating and informing people about the existence of the shark specie and its importance to the sea.

Sharks are one of the oceans top predators. They vary in size from the extremely small dwarf shark, to the colossal whale shark. Sharks can be found all across the world’s oceans, from the tropic waters of Hawaii to the sub zero temperatures in the Artic oceans. Of the hundreds of sharks a select few species have actually been recorded in the Artic. Of these few, only three of them spend the majority of their time in these harsh, freezing waters. These sharks are the Greenland, Pacific Sleeper, and Salmon sharks.

The Shark’s place in the marine ecosystem is as a predator at the top of the food chain as there is no natural predator of sharks. Sharks are not very fastidious about what they eat but their diet generally consists of seal, crab, squid, lobster and fish. If sharks were to become extinct there would be an ecological cost. The marine life that is the shark’s food source would start to overpopulate with nothing to prey on it. One possible reason that sharks are coming closer to shores is that their natural food source is diminishing due to overfishing by humans. To stop sharks from being too near to popular swimming locations, fishermen need to expand or change their hunting areas.

People visceral when they see a shark and they try to capture and kill it. Only some people want to protect sharks. Sharks help by keeping the fish population down First, we can protect sharks by doing little things such as stop finning sharks, picking up our trash. Next people destroy environments by oil spills. Not picking up trash. Last if people don’t stop finning sharks and not throwing their trash away our environment will smell bad and we will have no sharks left.

The cause of this debate comes with the return of White Sharks to the area. Over the past few years, there has been an increase of this apex predator to our coasts like never before seen, most notably since Labor Day weekend in 2009. Five sharks had been tagged by a marine biologist, Greg Skomal, and have been closely tracked and documented since. Skomal is a key player in this research as project leader

Sea Shepherd Conservation Society’s article “The Brutal Business of Shark Finning” reminds us that sharks play a key role in the ocean as both predators and scavengers.

The Eastern Grey Nurse Shark inhabits Australia as a genetically distinct population from its Western counterpart, and has been labeled a “Critically Endangered” animal by the Environment Protection and Biodiversity Conservation Act of 1999 ("Australian Threatened Species”). The population is found along the coast of Queensland and Narooma, the southern area of New South Wales, and various efforts have been put in place to conserve the species (“Grey Nurse Shark,” 2016). As such, the conservation methods put in place are not sufficient and further steps are necessary to allow the species to recover from its human-induced endangerment.

Sharks are being harvested in an irresponsible and unsustainable way. Many species of shark could go extinct within our lifetime. Overfishing has caused a dramatic decline of 90% for shark populations worldwide and up to a 99% decline on the US East Coast. (Jha, 2008) This issue is

Myers’ and Worm’s article “Rapid Worldwide Depletion of Predatory Fish Communities” (“Rapid Depletion”) focuses on the same pressing matter of overfishing, but their article gravitates more towards statistics and figures. For example, Myers’ article states that a suggested 90% of large predatory fish are no longer present in our oceans. Myers uses blunt facts to reveal the severity of overfishing to readers. Studies have concluded that for a given area of ocean opened up to commercial fishing, an 80% decrease in target species may be found in as little as 15 years. With numbers like this, it is no surprise that our oceans are in such a crippled state. Harmful methods of catching species

Recent studies from the article “Hammerhead shark migration gives new hope for conservation” discusses how these hammerhead sharks have been listed onto the IUCN (International Union for the Conservation of Nature) since 2007, also having certain regulation about international trade threatening species going extinct. Dr. Tristian Guthridge explains the benefits of understanding the shark’s behavior and more research of where these sharks are migrating, and possibly manage the time of fishing in the areas to eliminate human and shark altercations. With the wide spread of ocean water it can be difficult to study the traveling of sharks; however, the research group was able to tag the sharks “with both acoustic and satellite tag, and use photo identification and laser photogrammetry” (Charlie Huveneers).

As a first world country, we consume a first class quantity of seafood as well. Overfishing of marine resources jeopardizes not just our existence, but they are also vital in supporting various ecosystems. In this paper, a number of research articles and other review articles were examined to compose a picture of the overfishing crisis. The recent developments of Atlantic cod and squid are discussed in more detail to provide a pattern that may lead to empty oceans in the future.