The effects of low and highfrequencies on a fishes lateral line By : Zac Shely A period Mr. Pledger 12/06/11
introduction• There are many ways to paralyze fish.Vibrations, curtain herbs, chemicals, and frequencies. For a fish to be paralyzed by frequencies, they either need to be very low, or very high. Frequencies are used for everything, sonar, satellites, radio, warf are, and many other things. But not a lot of people have tested the effect of frequencies on fish or other organisms.
Question?• How high or how low does a frequency have to be for it to paralyze a common goldfish, And which frequency causes the fish to be paralyzed for the longest amount of time.
Research• A fishes lateral line, is a sensory organ that allows the fish to sense pressure change, movement from other fish and organisms, and vibrations in their surroundings. (http://www.laterallineco.com/fish_lateral_line.html Brandon & Spencer White Founders, Lateral Line, Inc. year 2008)• All fish have a lateral line, but depending on the fish, it can be used for different things such as, schooling, avoiding predators, preying on their food, or locating and attracting a mate. (http://www.laterallineco.com/fish_lateral_line.html Brandon & Spencer White Founders, Lateral Line, Inc. year 2008)• Also, fish can hear these frequencies in the water because it changes the pressure and they can sense this using their lateral line.
Research cont..• Some whales and dolphins have a unique ability which allows them to use a burst of sound that paralyzes fish so they can catch them easier. (Lamb, W. Kaye. "Canada." The Canadian Encyclopedia. Historica Foundation, 2007. 1 Sep 2007. http://www.thecanadianencyclopedia.com/index.cfm?PgNm =Copyright&Params=A1)• Scientist have been able to recreate this burst of sound and paralyze fish, but different levels of frequencies effect how long the fish is paralyzed for.• These frequencies range up to 200KHz
hypothesis• If I use different types of frequencies, consisting of low and high frequencies, on 3 different sized fish (small, medium, and large) and I keep the type of the fish and all other factors the same, how long will the fish be paralyzed?
Experiment• For this, I started off with three fish. A small (1 inch) a medium (1.5inch) and a large (2inch) fish, I kept them in a large 1½ foot glass vase. Using waterproof headphones I subjected the fish to hertz and kilohertz, ranging from 10hz- 22kilohertz. For every 1000hz, there is 1khz, so 22khz is 22,000hz. When the fish became paralyzed, I immediately turned off the frequencies and waited to see how long the fish were paralyzed for.
Experiment cont…• So over the next few hours I recorded all of the data and found that, The average amount of time the fish were paralyzed for while using hertz was 27 seconds. While the average for while using kilohertz was 25 seconds. These were at the highest and the lowest frequencies. I then put this data into two charts.
conclusion • During my tests, I though that the fish would be paralyzed steadily with every type of frequency, but a little bit more with the extremely low and extremely high points; But, they were only paralyzed with the extremely low and extremely high frequencies, and the ones in the middle they werent even effected by.This makes me wonder, if they can even sense the midfrequencies. Also, like I though, the larger fish was less effected by the frequency compared to the medium and smaller fish, this shows that the bigger the fish, the more of an immunity it has to the frequency, or maybe the smaller fishes lateral line isnt as developed as the larger fishes is.
Share results• To share my results, I posted my power point on “slide share.” (http://www.slideshare.net) A website where your able to upload any power point for anyone to look at, and hopefully other people will watch and learn from my power point, and maybe expand on it and learn even more.