Earlier this month, researchers from Woods Hole Oceanographic Institution (WHOI) created a new technique to locate fish, and even zooplankton, which eliminates the interference of turbulent waters.
In the past, marine biologists relied on sound waves to locate schools of fish and map the ocean floor. A sound wave was emitted from the surface, and as it traveled deeper into the ocean and made contact with an object, the sound wave would scatter. This information from the scattered wave was then used to determine the size and shape of the object. Unfortunately a single sound wave would rarely consist of more than one frequency and data from different frequencies vary. The inaccuracy of sound wave interpretation increases with seawater turbulence; scientists may not be certain if the small scatterings of sound waves are tiny zooplankton or interference of turbulent waters.
Recently, the researchers at WHOI published details surrounding a new and improved methodology which relies upon broadband systems to measure an array of frequencies, resulting in the broadband acoustic spectra. By incorporating a wider range of frequencies this novel method is also able to determine the population density of fish as well as individual size. Being able to gather such information is crucial for the commercial fishing industry. In regard to zooplankton, this device has the ability to distinguish between zooplankton and ocean turbidity. This new technique is such an advancement in the field, it is being compared to the switch from black and white to color T.V.
In the past, marine biologists relied on sound waves to locate schools of fish and map the ocean floor. A sound wave was emitted from the surface, and as it traveled deeper into the ocean and made contact with an object, the sound wave would scatter. This information from the scattered wave was then used to determine the size and shape of the object. Unfortunately a single sound wave would rarely consist of more than one frequency and data from different frequencies vary. The inaccuracy of sound wave interpretation increases with seawater turbulence; scientists may not be certain if the small scatterings of sound waves are tiny zooplankton or interference of turbulent waters.
Recently, the researchers at WHOI published details surrounding a new and improved methodology which relies upon broadband systems to measure an array of frequencies, resulting in the broadband acoustic spectra. By incorporating a wider range of frequencies this novel method is also able to determine the population density of fish as well as individual size. Being able to gather such information is crucial for the commercial fishing industry. In regard to zooplankton, this device has the ability to distinguish between zooplankton and ocean turbidity. This new technique is such an advancement in the field, it is being compared to the switch from black and white to color T.V.
More information may be found at: http://www.sciencedaily.com/releases/2010/04/100401135823.htm
