Ecological Systems and Devices Annotation << Back METHOD OF OPERATIONAL ACTIVE ACOUSTIC MONITORING OF GRAY WHALES IN THE AREA OF OFFSHORE OIL AND GAS FACILITIES L.E. Karachun, E.S. Kondrashova, A.E. Malashenko The use of the echolocation method for observing gray whales in areas of active industrial activity allows us to determine their location with high efficiency in fairly large water areas in conditions where other methods of observation are ineffective, for example: in the absence of acoustic signals issued by the whales themselves; in weather conditions that make visual observation difficult (storm surge, fog, rain). With the help of several special sonar systems operating in the echolocation mode, combined in a system with the transmission of information to observers via a radio channel through an anchored radio beacon, it is possible to observe such large biological objects as gray whales. The level of sounding signals should be no more than the level of sounds made by the whale itself, and sufficient for echo-finding at sufficiently large distances. Keywords: autonomous hydroacoustic complex; echolocation; noise direction finding; radiation pattern; signal-tonoise ratio. DOI: 10.25791/esip.11.2021.1263 Pp. 038-043.