The Effect of Underwater Acoustics on Whales
Whales utilize acoustic frequencies to communicate underwater. If the
whales are unable to communicate their bi-annual migration can become
perilous. Man-made low frequency sonarcan prevent whales from
producing soundand sometimes causes them to take alternate routes.
When the whales try to avoid the sonar they are in danger of running
ashore and perishing after being beached.
Introduction:
Twice a year, around the months of December and May, populations of
gray whales migrate from Mexico to Alaska. (Unknown1, 2002) During
this journey, they pass the state of California, where acoustical
pulses, generated by air guns or water guns, are used in seismic
surveys. If the seismic-generated sound waves exceed the "background"
noise or normal amount of noise, they could interfere with gray whale
communication or disturb behavior. (Unknown1, 2002) It is possible
that seismic surveys have a detrimental impact on marine life, such as
gray whales.
Whales are able to perceive sound in a wide range of frequencies from
75 Hz up to 150 Hz. In experimental conditions, where the
environment's level of noise is controlled, the whales are more
sensitive and hear from 10 Hz to 100 Hz. In addition, smaller whales
have a broader range from which they can hear from 10 up to 300Hz.
(Unknown2, 2002)
Whales depend on sound for communication, navigation, and even
detection of predators and prey. The seismic-generated sound waves may
disturb critical abilities. Disruption of any of their vital functions
can significantly disturb the fitness of whales. (Unknown3) There are
many factors that affect...
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Keeping these huge animals in small pools does not seem right. Big mammals are not meant to be in small pools. When these mammals are born they stay with there mother all of their lives. They never leave their mothers until they are captured and put in small pools which is not right. Killer whales hunt in pods, the oldest female in the pod is usually the group leader. Each pod has its own set of whistles, clicks, and calls that only members of the pod recognize similar to having a unique language. Members of many pods hunt in teams. For example, they may work together to create waves to knock a seal from an ice floe and into the open water. In many pods,...
This has been a tradition of the Makah Indians for more than 2000 years. They had to stop in 1926 due to the scarcity of gray whales. But their abundance now makes it possible to resume their ancient practice of the hunt.
“… building a tank the size of Rhode Island wouldn’t be large enough for a six-ton male killer whale such as Tilikum, an animal capable of swimming 100 miles a day,” states an anonymous whale expert. Whales have been in captivity since 1861 when P.T. Barnum displayed the first live whale that was captured in Canada. However, Barnum had no idea how to care for the mammal and it died after only a week in captivity. (Animal Legal and Historical Center, 2014) Being up close with killer whales could give us some clues about how they interact with each other, including physical behavior, their dialect, and how their pods work together as a family unit. However, what we are finding is that whales who belong in the wild are suffering in captivity. Killer whales have no record of ever harming a human being in the wild. In captivity, there have been many incidents of killer whales harming or even killing their trainers. What would cause them to do this in captivity, but not in the wild? They have been known to resort to aggression toward themselves and each other, in what scientist believe to be a stress induced behavior. (Animal Legal and Historical Center, 2014) Evidence against having these wild animals in captivity is increasing and we need reevaluate the value of capturing and holding killer whales for our educational purposes, enjoyment, and profit.
Shirihai, H. and B. Jarrett (2006). Whales, Dolphins and Other Marine Mammals of the World. Princeton, Princeton University Press. p.185-188.
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.
The book In the Heart of the Sea: The Tragedy of the Whaleship Essex by Nathaniel Philbrick, is an inspiring story about an Essex from Nantucket, getting attacked by a eighty-five ton sperm whale miles deep out in the ocean. In these times, going on any ocean expedition had its precautions. While much focus on food, drinking water, medication and a method to cure illness, the most overlooked impairment was the creatures of the ocean. While the men of this vessel left the docks as predators, the survivors of the ninety- three-day journey on three small harpoon boats came back as prey. This story gives a great depiction of the potential of the sperm whale as well as the devastation that they can bring.
The origin of modern day whales, a mystery that has puzzled paleontologists for years, may have just been solved with the discovery of an ankle bone. This discovery might sound simple and unimportant, but the bones of these ancient animals hold many unanswered questions and provide solid proof of origin and behavior. The relationship between whales and other animals has proven to be difficult because whales are warm-blooded, like humans, yet they live in the sea. The fact that they are warm-blooded suggests that they are related to some type of land animal. However, the questions of exactly which animal, and how whales evolved from land to water, have remained unanswered until now.
Nearly 500 whales beach themselves every year due to an excessive use of sonar. Military passive sonar (sound navigation and ranging) is killing and causing whales to avoid their major feeding and breeding grounds while temporarily deflecting from the high frequency sound coming from this unknown source. This event is raising hell in the political sector. Scientists have found many similarities between all the beached whales that have been in the same area that military sonar was being used. Military sonar is affecting the life of whales and their natural habitat for the worst.
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.
The main focus in this article is the two killer whales that died from mosquito
Sea Shepherd Conservation Society "The Makah Whale Hunt" 02 Online. Internet 3 Febuary 2003. Available www:seashepherd.org/media_info/asp.
Killer whales communicate by a series of clicks and whistles called vocalization. Each pod, or family, has their own unique language. This gives whales the ability to identify their own pods. Orcas have a brain that is about five ti...
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).
These dolphins are the type of dolphins common people would see at the Zoo or on a T.V. programed performance. Like the Common Dolphins, the Atlantic Bottle-Nosed Dolphins are highly skillful echolocators. They can produce a range of sounds, like a click, using it to analyze any object around them in the ocean (Whitfield 114). According to Whitfield on page 114, they can produce up to 100 clicks a second. They will use these clicks to also find food. They mainly eat Bottom-dwelling fish in inshore waters or surface swimming fish. They can do many other objects with their echolocation finder and using their