For the first time in Russia, including the Soviet period, was created the scientific sonar system capable of carrying out fish stocks state assessments. This new and unique system makes it possible to lessen monopolistic market position of the Kongsberg Maritime company (Simrad, Norway) which dominated the market of such kind of equipment over the past three decades. At the end of 2014, Vector Marine Electronics Ltd. completed development of the prototype of a portable multibeam sector-view sonar (coded as Sector) designed for fish calculation in protected coastal fishing areas and in internal water bodies (there is no such scientific equipment abroad). It is the first step to replace foreign imports necessary for investigation of marine bioresources. At the final stage of the development works a series of model and full-scale underwater tests were conducted.