Материалы по применению аэровизуальных методов в рыбохозяйственных исследованиях в северо-западной части Охотского моря

• Main Author: Пастырев, В.
• Format: Text
• Language: unknown
• Published: Федеральное государственное унитарное предприятие «Тихоокеанский научно-исследовательский рыбохозяйственный центр» 2007
• Subjects: Okhotsk; Pacific; okhotsk sea
• Online Access: http://cyberleninka.ru/article/n/materialy-po-primeneniyu-aerovizualnyh-metodov-v-rybohozyaystvennyh-issledovaniyah-v-severo-zapadnoy-chasti-ohotskogo-morya; http://cyberleninka.ru/article_covers/11169628.png

Даны рекомендации по планированию и проведению авиационных учетных работ по нерестовой сельди, мойве и лососям в период их анадромных миграций применительно к условиям северо-западной части Охотского моря. Подробно описаны особенности визуальной идентификации преднерестовых и нерестовых скоплений этих промысловых видов. Recommendations on planning and conducting of airborne visual surveillance (AVS) for spawning herring, pacific capelin, and pacific salmon during their alongshore migrations in the northwestern Okhotsk Sea and in rivers of the Okhotsk Sea basin are given. Features of visual identification of prespawning and spawning schools of these species are described in detail. Several abundant fish species create a basis for fishery in the northwestern part of the Okhotsk Sea: the herring, pacific capelin, and chum and pink salmons. They have vast spawning areas that make difficulties for their stocks estimation. Revealing of spawning grounds, migrating schools, timing of spawning migrations is necessary for direct account of fish stocks. However, it was almost impossible until the middle of 1960s, when the AVS started that gave an opportunity to investigate the spawning areas more completely. Despite of expensiveness of this method, the expenses are completely justified by high accuracy of estimation of the stocks of these valuable species. Until 1990, the Ilyushin IL-14 plane was used for AVS that had abilities for long routes, so the area of survey covered the vast area from the Taui Bay to Litke Cape. Since 1991, the AVS is based aboard the smaller Antonov AN-2 plane that has worse technical abilities (no navigational facilities, time of nonstop flight 6 hours, flight speed 150 km/h). As a result, the survey is shrunken to the area from Ayan to Lisyansky Peninsula. Highly important problem of AVS is identification of observable objects following to their characteristic signs. The fish species can be defined by form of their schools, by specific reaction to noise of plane's motors or to plane shadow, or by other signs that are discussed. Skilful pilot-observer can easily distinguish fish schools from spots of algae, reefs, shadows of clouds, trees, etc. and define species of fish in schools. Even single fish is well recognized from the plane. The count technique for salmons has some specific features for each river because of different hydrological mode, relief, and some other reasons. However, the main features of spawning salmons behavior are practically equal in any river: form of schools and distance between individuals are rather stable and definitely conditioned by water dynamics and magnetic field. The main foundations of count technique for salmons in rivers are described.