Whales Have Sonar "Beam" for Targeting Prey

The article, “Whales Have Sonar “Beam” for Targeting Prey” written by Christine Dell’Amore describes how toothed whales are able to track fast moving prey in the water by using a “constantly shifting, tightly focused sonar beam.”  Echolocation is the skill that all toothed whales and dolphins have, where they click loudly using special nasal structures and listen for echoes bouncing off objects.  By focusing these clicks into a type of sonar beam, whales are able to efficiently track fast moving prey.  This skill is quite necessary for their survival, as without it, they would most likely not be able to acquire food, as their eyesight proves little to no use underwater, especially when it gets deeper and darker.  Study leader Laura Kloepper, a zoologist at the University of Hawaii at Honolulu, explains this quite clearly.  She says, “The bottom line is echolocation is how these animals make their living. Not only do they have to locate fish, they have to discriminate fish and figure out what kind of fish it is—it's this constant underwater dance between predator and prey.”  This explains why there has to be some sort of focusing going on, or else whales would have no idea what they were eating, if they could even find anything in the first place.  To do some tests, the team worked with Kina, a false killer whale at the University of Hawaii with large amounts of previous training.  In the first experiment, Kina was instructed to swim into an underwater hoop up to her pectoral fins.  Next, a soundproof door was lowered, and Kina then echolocated on a target, a hollow cylinder similar to a toilet paper tube.  “Kina had previously been trained to recognize the thickness of this particular cylinder and to signal this by touching a button with her snout, which earned her a fish reward.”  Kina was then presented with two other types of cylinders in order to test her echolocation skills: one with much thicker walls, which she could detect easily, and another with only slighter thicker walls, which presented more a challenge for Kina to pinpoint.  “While Kina was echolocating the various targets, an array of underwater microphones were measuring her constant barrage of sonar waves.”  After analyzing the data, scientists discovered that Kina’s beam shape had changed depending on the cylinders’ distances and differences.  Kloepper explained that this could be compared to how an eye continuously refocuses on an object.

            This article is important to society because it shows how much more we can still learn about so many things in the world.  Although it may seem as if we know a lot, I can guarantee we have barely scratched the surface, and this newly found information on whales demonstrates how we can learn new things every day.  Plenty of echolocation mysteries remain, however.  For example, scientists are still not sure how whales can hear properly even while clicking incredibly loudly (the focus of the study team's next project).  "The more information we obtain on their ability to manipulate the beam," Houser said, "the more complicated the story becomes."  I chose this article because although I had heard about it, I was interested in how whales could locate things around them and find food in the ocean when their eyesight was not very helpful.

             I found this article to be perfectly written.  After reading it carefully, there was not much I could critique on the article as I found the way it was put together to be very effective and easy to understand and see what they were trying to accomplish.  For example, the first paragraph was basic information on the topic that the reader would need to understand in order to go on further in the article.  Then, the second paragraph was the experiment and some of the results.  And lastly, the third paragraph analyzed the results and explained what it meant to us.

Dell'Amore, Christine. "Whales Have Sonar 'Beam' for Targeting Prey."

     National Geographic 22 Mar. 2012: n. pag. National Geographic. Web. 25

     Mar. 2012. <http://news.nationalgeographic.com/news/2012/03/

     120322-whales-echolocation-sonar-ocean-animals-science/>.