Introduction
The blue whale (Balaenoptera musculus) is a species of baleen whale known as the largest animal on Earth. They can grow to be over 100 feet long and can weigh up to 165 tons. Blue whales are found in all oceans and can occupy a wide variety of habitats, from pelagic environments to offshore environments (Clapham et al. 1999).
Up until the 19th century, blue whales were generally immune from whaling. Not only were they substantially large animals, they were also very quick and agile and were difficult to catch. However, the invention of the steam engine and explosive harpoon allowed whalers to regularly catch this animal (Clapham et al. 1999). During the early 20th century, a whaling ground was opened in the Southern Ocean of which blue whales became the primary target species. Over 360,000 blue whales were kill during that century in the Antarctic region alone. Finally in 1966, the International Whaling Commision [IWC] banned commercial whaling for blue whales (Reilly 2013). Even so, former fleet members of the USSR navy continued to exploit this and other species until the 1970s. In 1986, the species was listed as ‘endangered’ by the International Union for Conservation of Nature [IUCN] (Clapham et al. 1999).
Almost 30 years later, the status of the species has not changed (Reilly 2013). Although commercial whaling is no longer a concern, there are many other threats to this species that have garnered attention over the years. Today, anthropogenic noise, fisheries interactions, and ship strikes all threaten the status of this species (Reilly 2013). For this paper, I will be focusing on the effects ship strikes have on the blue whale population.
Habitat and Distribution
Blue whales are found in all oceans worldw...
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...J. V., McKenna, M. F., Moore, T. J., Calambokidis, J., Deangelis, M. L., Becker, E. A. & Chivers, S. J. (2013). Assessing the risk of ships striking large whales in marine spatial planning. Conservation Biology, 27(2), 292-302.
Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. 2008. Balaenoptera musculus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2.
Ritter, F. (2012). Collisions of sailing vessels with cetaceans worldwide: First insights into a seemingly growing problem. Journal of Cetacean Research and Management, 12(1), 119-127.
Shurin, J. B., Gruner, D. S., & Hillebrand, H. (2006). All wet or dried up? Real differences between aquatic and terrestrial food webs. Proceedings of the Royal Society B: Biological Sciences, 273(1582), 1-9.
Robert L. Pitman. "Whalewatcher: Killer Whale: The top, top Predator ." Journal of the American Cetacean Society (2011): 2. Journal.
In the past twenty years a large amount of bottlenose dolphin have been killed due to the tuna fishery. In the Eastern Pacific swim large schools of tuna, these shoals tend to be under herds of dolphins, for some unexplained reason. Because of this, fishermen can easily find schools of tuna. The tuna are being caught under purse seine nets, which encircles the shoals of tuna and then is pulled back on board the fishing vessel, catching both tuna and dolphin. Initially the mortality rate was 500,000 each year for dolphins alone. Although some efforts are made to encourage the dolphins to leave the net by backing down part of the net, which allows the dolphins to escape, there are still a large number of mortalities (Bryant). On the other hand, in the last few years there has been dramatic progress in stopping the fishing industries from using purse sine nets. It has been found that dolphins are in immediate danger of extinction if these fishing techniques don’t stop.
Reza, H. G. "Whales Collide, 1 Is Fatally Injured in Sea World Tank." Los Angeles
U.S. Department of the interior, National Park Service. (2013). Endangered Species. Retrieved from website: http://www.nature.nps.gov/biology/endangeredspecies/index.cfm
Soule, Michael E et al. “Ecological Effectiveness: Conservation Goals for Interactive Species.” Conservation Biology 17.5 (2003) : 1238-1250.
The Makah’s seemingly domestic issue of whaling has and is taking on a larger international problem. The United States plays a large part in policing the hunting of whales, one of the most recent examples being the U.S.’s ...
In this research report I will discuss the Killer Whales unique characteristics; complex migratory patterns, how and why it is endangered, and most importantly how we can help them.
After watching several documentaries on how poorly killer whales are treated in captivity, it drew me into researching more information on the treatment of Killer whales that are kept in captivity. I found several scientific journals, and articles on wild life facts of killer whales and I found published books on the treatment of killer whales in captivity. The information I found includes both wild killer whales and killer whales kept in captivity. With the information I found, I plan to prove the shortened lifespan and health problems killer whales get while living in captivity are not normal. In fact the information you learned about killer whales from aquariums and commercial parks are false. This paper will argue why killer whales should not be held captive in commercial parks. This Paper will include information on the killer whale’s diet, the killer whale’s communication, and the killer whale’s physical traits.
Orcas, also known as killer whales, are amazingly intelligent and are a top predator, much like humans. However, when the top predator of the ocean collides with the top predator of land, the situation can become fatal for both humans and the whales. Holding these incredibly massive marine animals in captivity is not only inhumane and detrimental to the whale’s health, but also a potentially fatal activity for humans to participate in.
Currently, live whale performances have become well liked for tourists to visit. When they are there, they only see what they want to see and do not care or want to know all about the complications the whales go through just to make people smile. The documentary “Blackfish” exposes the truth about the whales, their habits, and why they act the manner they do when in captivity. The inhumane treatment of whales in captivity causes negative effects on the animals which, in turn, affects the humans who care for them.
Mills, Scott L., Daniel F. Doak, and Michael E. Soule. "The Keystone-species Concept in Ecology and Conservation." BioScience 43.4 (1993): 219-25. Apr. 1993. Web. 30 Oct. 2011.
The quest to gain international agreement on ethical and legal norms for regulation of whaling has had a long and troubled history. The modern phase of global concern over whaling ethics and conservationist management originated in 1946, when the International Convention on Regulation of Whaling was signed. Thus, the International Whaling Commission was created. The International Whaling Commission was designed to control and mandate the whaling industry. From it’s beginning as simply a whalers club with scientific guidance, to the current day conservationist body, the IWC has undergone many revisions and transformations since the start.
Orcas, or killer whales are majestic giants of the sea. They are actually the largest type of dolphin. They have long black bodies with distinct white patches near their eyes. A killer whale can be up to 32 feet or more in length, and weigh up to 12,000 pounds. Females are a bit smaller, but live longer (Gorman). The name “killer whale” apparently came not because it is a vicious whale, but because it preys on whales. They do not have any natural predators, and they are considered the “top dog” of the ocean. Not even the great white shark stands a chance against these superb killers. “Unlike sharks, killer whales are cautious hunters, sometimes spending hours harassing a 1,000-pound sea lion so it can easily be drowned” (Francis). Orcas use many hunting tactics that are unique to their species, which is what makes them invincible.
...r humans because killer whales are one of the world's most powerful predators. Perhaps the greatest threat to the killer whales comes from the disturbance and degradation of its habitat. As a top predator, the killer whale is particularly vulnerable to the accumulation of contaminants in its tissues; for example, some populations have been found to carry high levels of chemicals such as PCBs (polychlorinated biphenyls), with negatively affects survival and reproduction. Large-scale oil spills can also affect the killer whales, either directly, or indirectly by reducing the abundance of its prey. Disturbance from boats and other man-made underwater noises can affect their behavior, disrupt echolocation and social calls, and reduce the ability of orcas to forage effectively. This may become a problem in areas where whale-watching is becoming popular. (Arkive).
The Humpback Whale, Megaptera novaeangliae, is part of the marine mammals group. They are found in oceans all over the world, they live in open waters. Even though they are mammals, they do not live on land (Monterey Bay Aquarium). Humpback whales are known for their magical song that can travel great distances. These gentle giants are omnivores, their main diet is krill. They are mostly found near coastlines feeding on tiny shrimp-like krill, plankton and small fish. Humpbacks migrate annually from summer feeding grounds near the poles to warmer winter breeding water closer to the Equator. Humpback whales are powerful swimmers, and they use their massive tail fin, called a fluke to propel themselves through or even out of the water! Mothers and their young swim close together, often touching one another with their flippers with what appears to be gestures of affection. Even though it takes more than one year for a humpback whale to grow fully, mother whales leave them after one year (National Geographic).