Megalodon

Reviving the Megalodon, a Jawesome Idea

By Austin Moore, Baron Lin, Ashley Sharpe, Benjamin Boyette

A twenty five foot long, 3 ton, monster has haunted the minds of American moviegoers since 1975, when Stephen Spielberg cast a great white shark as the antagonist of his popular film “Jaws”. (Academics and nature enthusiasts heavily criticized the film, claiming it painted an awful misrepresentation of sharks’ true nature. Sharks annually kill 5.5 people worldwide, while in 2012 dogs were responsible for 39 deaths within the U.S. alone.) Imagine reviving a leviathan shark that would reach between 45 – 65 feet in length, weigh around 55 tons, and still be safer than man’s best friend.

There are many unknowns about the giant Chacharodon megalodon, but according to the dominant theory, it was the apex predator of ocean waters during the Cenozoic and Pleistocene Era up until 1.5 million years ago. Then it is believed that the Ice Age dropped ocean temperatures and introduced a variety of obstacles that megalodon was unable to overcome. As a warm water shark, the cooling water disrupted its habitat range and migration routes. Following the change in environment their food sources, most likely some type of whales, began to relocate and the megalodon was unable to compete with new apex predators infringing upon its dwindling territory.

The Megalodon was a perfectly adapted specialist that was unmatched in its apex status. The shark primarily inhabited the deep, open ocean waters, migrating to chase down prey according their seasonal movements. Megalodons were viviparous organisms, meaning they gave birth to live young, and moved to warm coastal waters to reproduce, therefore ensuring the safety and survival of their offspring. Within their nurseries, juveniles predated upon smaller marine mammals such as seals and porpoises until they were large enough to move into pelagic waters. Due to the long period since extinction and few numbers of fossils, there is a great deal of uncertainty on details of the megalodon. Because of this, we base much of our knowledge about it on the great white shark. Since it is considered to be the most similar living species to the megalodon, a great white shark would be used to facilitate the development and birth of the cloned or genetically engineered megalodon offspring. Great whites are homeothermic organisms meaning that they maintain a constant body temperature. They accomplish this by staying in water that is near their optimal temperature as well as through as using a network of capillaries and blood vessels (known as rete mirabila) that their swimming muscles warm. Great sharks navigate by using a strong sense of smell, eyesight, and the ability to detect electromagnetic fields, and these traits are likely ancestral to the megalodon as well.

Before introducing the megalodon, it needs to be determined if their habitat still actually exists. Megalodons inhabited open ocean waters, but would those areas be suited for their return? Warming water temperatures caused by climate change increase the range and suitability of potential megalodon habitats. Great white sharks seasonally frequent the open ocean as well, but it is unknown as to why. This may be for reproduction, but it is just as likely that they are hunting food sources that we are unaware of. We can thus imply that the megalodon would be able to nourish itself on the same prey: schooling fish, diving whales, or maybe even giant squid. Megalodons most likely used warm coastal waters as nursery habitats. It is believed that areas similar to those used in the past still exist today making this a critical type of habitat for juvenile survival and the viability of the population as a whole.

Reintroduction would most certainly have effects upon the existing ecosystems and because they cannot be predicted, are of great concern. It is likely that the appearance of such a capable apex predator would put great strain on existing relationships amongst trophic levels and exert heavy top-down control on the entire food chain. A first concern with these impacts would be if their predation would lead to extinction or endangerment of any extant species particularly some whale species that are already in decline. The biggest threat would be the removal of a keystone species through direct predations, or as an inadvertent result of the megalodon’s existence, which would result in a disastrous trophic cascade. For example, if killer whales were to disappear, a surplus of sea otters would occur, which would decline urchin populations who feast upon kelp forests, which would ultimately block out sunlight in their waters and lead to nutrient eutrophication of the waters. An equal concern would be if the sharks would adversely affect a flagship species, one that is widely regarded and adored by the public. The removal of such an organism would immediately garner negative attention to the megalodon, regardless of any benefits it provides to industry and the environment.

Successfully managing the reintroduced population is presumably difficult due to megalodon’s large size and superior predatory skills, yet is entirely possible if the guidelines below are adhered to and modified as needed once the population’s been established. Initial reintroduction would involve the release of two groups of breeding age pairs in the Pacific ocean. The exact number of released megalodons would depend on the success of the de-extinction and rearing of breeding stock in captivity. Depending on the success of this rearing program, one group of approximately 10 male/female pairs would be established off the coast of California and another off the coast of Chile. Each megalodon would be tagged with a GPS tracking unit to allow research on the re-introduction as well as to monitor its success. Monitoring and study would continue to be conducted to observe the success and health of the population as well as impacts it was having on the ecosystem as a whole. Based on these factors it is possible that a controlled harvest would be implemented with international regulatory commissions as overseers. Newspaper and scientific journal/magazine articles would be published to inform the public of the reintroduction and management plans. However, since the majority of Americans do not access these sources, they would be informed of successful reestablishment of wild megalodon populations during the world’s greatest premier of “Shark Week”. Long-term public support would be gained by the variety of economic benefits that the megalodon shark is able to provide. Due to their large size, fishery catches would yield higher profitability at a lower cost. This would reduce strain on the exploitation of extant shark species, and allow the over-fished to begin their recovery. Currently sharks in the Bahamas generate $78 million dollars of annual revenue from ecotourism. Imagine the impact that interest that a species as large as the megalodon will generate.

The megalodon must be respected for its capabilities and size. Despite any ecological and economic concerns, reintroduction and management is possible. By introducing small initial populations that are allowed to slowly grow to a capped size, ecosystem impacts will be minimized. Its de-extinction will also provide a unique opportunity for research that could be valuable for the possible de-extinction of other species in the future. The distance that adults are released offshore, and the rarity in which they visit coastal waters make human dangers less likely. The megalodon will generate a lot of public attention and interest, which boosts sustainable economic ventures and promotes the importance of conservation. It is recommended that if the above guidelines and surrogate species are adhered to, the megalodon should be resurrected from extinction.

Suggest further reading:http://link.springer.com/content/pdf/10.1007%2Fs00227-007-0739-4.pdf

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0010552