Влияние миног и некоторых других животных на утилизацию вещества морского происхождения в лососевых реках

• Main Authors: Кучерявый, Александр, Пельгунова, Любовь, Савваитова, Ксения, Павлов, Дмитрий
• Format: Text
• Language: unknown
• Published: Федеральное государственное унитарное предприятие «Тихоокеанский научно-исследовательский рыбохозяйственный центр» 2010
• Subjects: ЭЛЕМЕНТНЫЙ СОСТАВ; МОРСКОЙ СИГНАЛ; ТИХООКЕАНСКАЯ МИНОГА; ТИХООКЕАНСКИЕ ЛОСОСИ; ДЕСТРУКЦИЯ; ПИТАНИЕ; УТИЛИЗАЦИЯ МОРСКОГО ВЕЩЕСТВА; Arctic; Pacific; Utkholok; Kamchatka; КАМЧАТК*
• Online Access: http://cyberleninka.ru/article/n/vliyanie-minog-i-nekotoryh-drugih-zhivotnyh-na-utilizatsiyu-veschestva-morskogo-proishozhdeniya-v-lososevyh-rekah; http://cyberleninka.ru/article_covers/12601543.png

Во время массовой посленерестовой гибели тихоокеанских лососей рода Oncorhynchus в р. Утхолок (западная Камчатка) исследовано распределение трупов лососей в разных биотопах. Определено количество морской органики (масса сырого белка и фосфора) и энергии, привносимых ими в реки. В соответствии с разработанной авторами системой оценки степени разложения тихоокеанских лососей изучена их колонизация разными макродеструкторами. Пескоройки тихоокеанской миноги появляются на трупах лососей только после превращения внутренних органов и мышц в кашицеобразную массу, когда они становятся доступным для них кормом. На основании анализа элементного состава исследованы степень выраженности "морского сигнала" (специфического соотношения химических элементов) в трупах лососей и личинках миноги. Установлено, что в организмах пескороек, извлеченных из трупов лососей, этот "сигнал" присутствует. When Pacific salmons (Oncorhynchus) migrate to spawning grounds, they bring thousands tons of organic matter into ecosystems of salmon rivers. Decaying corpses of the fish which die after the spawning are an important source of productivity. This matter of marine origin makes significant effect on freshwater ecosystems, their structure and biological diversity. Mechanisms of the processes that determine this effect are still poorly understood. In particular, the role of lampreys is unknown yet, and an idea on ammocoetes as consumers of the lowest level which feed exclusively on low-calorie detritus prevails. There is found from the research of the Arctic lamprey (Lethenteron camtschaticum) population in the Utkholok River (West Kamchatka) that both adults and larvae of this species can consume animal food: the larvae of lamprey actively feed on decaying corpses of salmons. Role of the lamprey larvae destructors in recycling of organic matter, macroand micronutrients brought into the river by chum and pink salmons is estimated using two approaches: 1) analysis of decomposition degree and number of scavengers for randomly selected dead corpses of salmon; 2) studying of decomposition and settlements of scavengers in trap catches. "Marine signal" (specific ratio of chemical elements in dry muscle tissue) was detected both in carcasses of salmons and bodies of lamprey larvae by means of the X-ray fluorescence spectrometer Roentek Picotax (Germany). Daily incomes of organic matter and microelements of marine origin were calculated from the number of dead salmon corpses per square meter. Influence of the processes of marine organic matter utilization on population structure of Arctic lamprey is studied, as well. Values of the matter of marine origin in different parts of the river are different and its distribution is mosaic. Most of dead salmon corpses decay on gravel shoals and in pools with slow flow. Numbers of scavengers inside and on salmon corpses were evaluated. Ammocoetes were found within the carcasses, in all parts of the river. They belonged to different age groups (from 0+ to 4+, except metamorphic ones). The lamprey larvae appeared in the carcasses of medium decomposition (20-60 %), when the half-decayed fish tissues became available to provide the ammocoetes with fats and proteins that increased their energy status. The tissues of lamprey larvae found within dead salmon corpses had a distinctive "marine signal", while it was absent or very weak for the larvae collected in the river before mass mortality of salmons. The lamprey smolts migrating for foraging to the sea had a weak "marine signal" and their gonads were less developed in compare with the individuals remained in the river who had the highest "marine signal". These patterns indicate that the ammocoetes, transformed to resident lamprey, feed mostly on animal food of marine origin, i.e. decaying corpses of salmon. The tissues of lamprey smolts and resident juvenile lampreys also differ on such crucial indicators as phosphorus content (measure of energy reserve) and sulfur content (indirect indicator of protein): the resident lampreys have higher content of these elements, close to their content in the tissues of lamprey larvae within corpses of dead salmon. There is assumed that consumption of organic matter of marine origin influences significantly on the lamprey development and formation of strategy for future life history of this species.