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Динамика популяционных показателей щуки Esox lucius L. (Esocidae) Р. Анадырь за период 1971-2010 гг.

Динамика популяционных показателей щуки Esox lucius L. (Esocidae) Р. Анадырь за период 1971-2010 гг.

Abstract

Samples of pike were collected by Lab. of Ichthyology, IBPN FEB RAS in the middle stream of the Anadyr River at Markovo in June-September of 1971-2010 and processed by standard methods; in total 2410 specimens were analyzed. The pike population changed significantly during the period of observation: the fish in catches became smaller and younger, growth rate decreased, and absolute and relative fecundity increased, mainly under impact of fishery, including industrial one that intensified in 1970-1980s. As the result, the pike abundance decreased in 1980s, and the first-spawning females and males became to prevail in its catches. Further decreasing of the abundance was able to promote a reduction of competition in the population. The population could be restored only after considerable decrease of fishing pressure, or banning of the species fishery, that would improve the feeding conditions. Recent lowering of the fishing pressure due to low stock causes partial recovery of the population accompanied by heightening of elder fish portion. Now the fish spawned several times prevail in the catches. However, the growth rate and females fecundity still differ from the values typical for the 1970s. Partial recovery of the pike population should be accounted in estimations of its predatory on other fishes in the Anadyr River, including commercial species.

Обобщены данные по возрастной и размерной структуре, линейному и весовому росту, а также плодовитости обыкновенной щуки Esox lucius L., собранные в р. Анадырь (район Марковской поймы) в период 1971-2010 гг. Интенсивность промысла влияет на изменение структуры популяции щуки. При сильной промысловой нагрузке наблюдалось значительное омоложение облавливаемого стада, снижался темп роста особей, отмечалось увеличение плодовитости самок. В условиях снижения или полного прекращения промысла щуки нами отмечено медленное восстановление ее популяции и возвращение к состоянию, сходному с таковым в 70-е гг. прошлого столетия. С другой стороны, ослабление промысла приводит к увеличению численности щуки и, соответственно, усилению ее пресса (как облигатного хищника) на окружающее сообщество рыб.

Keywords

ОБЫКНОВЕННАЯ ЩУКА, Р. АНАДЫРЬ, РАЗМЕРНО-ВОЗРАСТНАЯ СТРУКТУРА, ЛИНЕЙНЫЙ И ВЕСОВОЙ РОСТ, УРАВНЕНИЕ БЕРТАЛАНФИ, ПЛОДОВИТОСТЬ, ПРОМЫСЕЛ

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selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
0
Average
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