Table of Contents
International Journal of Oceanography
Volume 2013, Article ID 678621, 9 pages
Review Article

The Development of SONAR as a Tool in Marine Biological Research in the Twentieth Century

1National Museum of Natural History, Department of Invertebrate Zoology, Smithsonian Institution, Washington, DC, USA
2AGUAtech, Via delle Pianazze 74, 19136 La Spezia, Italy

Received 3 June 2013; Revised 16 September 2013; Accepted 25 September 2013

Academic Editor: Emilio Fernández

Copyright © 2013 John A. Fornshell and Alessandra Tesei. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The development of acoustic methods for measuring depths and ranges in the ocean environment began in the second decade of the twentieth century. The two world wars and the “Cold War” produced three eras of rapid technological development in the field of acoustic oceanography. By the mid-1920s, researchers had identified echoes from fish, Gadus morhua, in the traces from their echo sounders. The first tank experiments establishing the basics for detection of fish were performed in 1928. Through the 1930s, the use of SONAR as a means of locating schools of fish was developed. The end of World War II was quickly followed by the advent of using SONAR to track and hunt whales in the Southern Ocean and the marketing of commercial fish finding SONARs for use by commercial fisherman. The “deep scattering layer” composed of invertebrates and fish was discovered in the late 1940s on the echo sounder records. SONARs employing high frequencies, broadband, split beam, and multiple frequencies were developed as methods for the detection, quantification and identification of fish and invertebrates. The study of fish behavior has seen some use of passive acoustic techniques. Advancements in computer technology have been important throughout the last four decades of the twentieth century.