Migration and Homing Behavior of Chum Salmon Tagged in the Okhotsk Sea, Eastern Hokkaido

Dependence of chum salmon Oncorhynchus keta recruitment (number of mature adults) in Okhotsky district located on the Okhotsk Sea coast on a number of spawners is analyzed for the spawning years of 1983–2014. During this period, the progeny abundance increased, then stabilized on a high level, then decreased. Generally, the number of recruits depended poorly on the number of spawners because of clear environmental impact. Indeed, the recruitment variation could be simulated on the base of Ricker curve with addition of a variable responsible for environmental trend. Number of the year of spawning was used as such variable. So, the chum recruitment R is modeled as R = a. P. exp(–(P/b + ((X – c)/d)2 )) for the period of increasing and R = a. P. exp(–(P/b – ((X – c)/с)2 )) for the period of decreasing, where P — number of parents, X — year of spawning, and a, b, c, d — empirical coefficients. This model explains > 80 % of the recruitment deviation. The environmental impact was weak in the period of stable recruitment, so the direct dependence of progeny abundance on spawners number (Ricker curve) can be used for these years, with similar determination (r2 > 0.8). This approach is proposed as a possible compromise between hypotheses on climate-driven and autoregulating mechanisms of the salmons abundance variability.

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Migrations of juvenile chum salmon in the Okhotsk Sea; comparative analysis of efficiency for fish hatchery complexes in Far East of Russia and in Japan

Izvestiya TINRO ◽

10.26428/1606-9919-2017-191-79-96 ◽

2017 ◽

Vol 191 ◽

pp. 79-96

Author(s):

Eugene A. Shevlyakov ◽

Alexandra I. Chistyakova

Keyword(s):

Comparative Analysis ◽

Chum Salmon ◽

Far East ◽

Far East Of Russia ◽

Okhotsk Sea ◽

Fish Hatchery ◽

Juvenile Chum Salmon

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Feeding and food supply of salmons in the Okhotsk Sea in autumn of 2018-2019

Izvestiya TINRO ◽

10.26428/1606-9919-2021-201-177-190 ◽

2021 ◽

Vol 201 (1) ◽

pp. 177-190

Author(s):

N. A. Kuznetsova ◽

O. I. Pushchina ◽

M. A. Shebanova

Keyword(s):

Chum Salmon ◽

Pink Salmon ◽

Species Abundance ◽

Zooplankton Biomass ◽

Okhotsk Sea ◽

Daily Consumption ◽

Daily Production ◽

Taxonomic Groups ◽

Favorable Conditions ◽

Total Zooplankton Biomass

In the autumn months of 2018-2019, food spectra of salmons were quite diverse in the Okhotsk Sea. Amphipods prevailed in the diet of juvenile pink and chum salmon that corresponded to these zooplankton species abundance in the southern part of the sea; other significant portions of their diet were presented by euphausiids, copepods, arrowworms, pteropods, and oikopleura. Decapods, fish and squids were in the diet of masu, coho and chinook salmon. Portion of zooplankton was about 100 % in the diet of pink salmon fingerlings, but only 98 % in the diet of chum salmon fingerlings with 2 % portion of squids. Grazing by salmons was insignificant: 0.2-0.3 % of the total zooplankton biomass within the periods of observation (18 days in 2018 and 13 days in 2019), or 0.04-2.0 % for certain taxonomic groups, except of pteropods and oikopleura with the consumed portions of 4-7 % and 7-12 %, respectively. However, the daily consumption by salmons relative to daily production of some groups was significant in October, 2018 and reached 97 % for amphipods and > 200 % for euphausiids in the northeastern Okhotsk Sea (biostatistical areas 6-8) and 48 and 27 %, respectively, in the entire surveyed area. This ratio was twice lower in October, 2019, as 24 % for amphipods and 12 % for euphausiids. Daily consumption of copepods and arrowworms never exceeded 2 % of their daily production. The most favorable conditions for nekton feeding in fall of both years were observed in the northwestern Okhotsk Sea, and the worst conditions — in its northeastern part, with moderate conditions without deficit of prey in the central part (biostatistical area 9) and southern part (biostatistical areas 12, 13), where the biomass of forage plankton exceeded the biomass of nekton in 30-97 times in 2018 and in 56-76 times in 2019.

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Expression of GnRH genes is elevated in discrete brain loci of chum salmon before initiation of homing behavior and during spawning migration

General and Comparative Endocrinology ◽

10.1016/j.ygcen.2010.05.001 ◽

2010 ◽

Vol 168 (3) ◽

pp. 356-368 ◽

Cited By ~ 9

Author(s):

Takeshi A. Onuma ◽

Keita Makino ◽

Hironori Ando ◽

Masatoshi Ban ◽

Masa-aki Fukuwaka ◽

...

Keyword(s):

Chum Salmon ◽

Spawning Migration ◽

Homing Behavior

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Juveniles of pink and chum salmon in the Iska River (Sakhalin Bay, Okhotsk Sea) in the fresh-water period

Izvestiya TINRO ◽

10.26428/1606-9919-2015-182-55-68 ◽

2015 ◽

Vol 182 (3) ◽

pp. 55-68

Author(s):

Albina N. Kanzeparova ◽

Sergey F. Zolotukhin ◽

Valery A. Balushkin

Keyword(s):

Fresh Water ◽

Chum Salmon ◽

Okhotsk Sea

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Juveniles of pink and chum salmon in the southern Okhotsk Sea in their late marine stage (August-October 2012). Distribution, feeding, patterns of growth

Izvestiya TINRO ◽

10.26428/1606-9919-2014-176-51-61 ◽

2014 ◽

Vol 176 (1) ◽

pp. 51-61

Author(s):

Artem Е. Lazhentsev ◽

Olga А. Maznikova

Keyword(s):

Growth Rate ◽

Chum Salmon ◽

Feeding Activity ◽

Pink Salmon ◽

Partial Replacement ◽

Linear Growth Rate ◽

Caloric Content ◽

Okhotsk Sea ◽

Water Cooling ◽

Feeding Intensity

Ontogeny of one generation of pink and chum salmons is described for the period after their juveniles redistribution from coastal waters to deep-water areas in the central and southern Okhotsk Sea in August-November, 2012. The juveniles fed very intensively in August when their diet had about 85 % of proteins and 15 % of lipids due to prevalence of hyperiids and oikopleuras with low fat content. Their growth rate was high at this stage, and energy expenditure on growth took about a half of the ration (56-63 % for pink salmon and 40 % for chum salmon). The feeding intensity became lower in October, but caloric content of the food increased because of partial replacement of its protein fraction by lipids, which content exeeded 75 %. Linear growth rate decreased in October in 3.8 times for pink salmon and in 1.8 times for chum salmon, it took 21-27 % of food energy for the pink and almost the same portion as in August for the chum. Both feeding activity, growth rate, and fat deposit depended on temperature. Temperature in August was more favorable for feeding and metabolic processes, in particular for pink salmon that was able to consume daily up to 1/10 of its body weight and spend > 50 % of the energy for the growth, but water cooling in October caused lesser feeding, lower metabolism, and slower growth.

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CHEMICAL COMPOSITION AND ENERGY CONTENT OF PACIFIC SALMONS IN THE OKHOTSK SEA

Izvestiya TINRO ◽

10.26428/1606-9919-2019-197-152-165 ◽

2019 ◽

Vol 197 ◽

pp. 152-165

Author(s):

K. M. Gorbatenko ◽

I. V. Melnikov ◽

E. E. Ovsyannikov ◽

S. L. Ovsyannikova

Keyword(s):

Total Energy ◽

Chum Salmon ◽

Energy Content ◽

Minimum Energy ◽

Pink Salmon ◽

Maximum Energy ◽

Okhotsk Sea ◽

The North ◽

Juvenile Chum Salmon ◽

The North Pacific

The main bioenergetic parameters of pacific salmons are presented on the data obtained in marine expeditions in 2003–2015. Among the examined species, the minimum energy content is registered in the muscle tissue of chum salmon and pink salmon, and the maximum energy content — in the muscles of king salmon. Total amount of the energy accumulated by juvenile pink salmon during its life within the Okhotsk Sea is estimated as 532 kcal or 27 % of the total energy accumulated in the whole marine period of its life, for juvenile chum salmon this amount is 492 kcal (11 %). The rest is accumulated by adults during their feeding in the ocean: pink salmon, without ranking by age and sex, gains in the North Pacific on average 1 442 kcal or 73 % of the total energy accumulated in the marine period of life, chum salmon — 4 071 kcal (89 %).

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