TEMPERATURE CONDITIONS IN THE COASTAL WATERS OF EASTERN SAKHALIN AND ITURUP ISLAND DURING THE APPROACH OF PINK SALMON AND CHUM SALMON FOR SPAWNING IN 2001–2017 YEARS (ODD YEARS)

Author(s):  
V.A. Tsareva ◽  
◽  
G.P. Vanyushin ◽  
M.Y. Kruzhalov ◽  
E.V. Sapunova ◽  
...  
1992 ◽  
Vol 58 (8) ◽  
pp. 1393-1397 ◽  
Author(s):  
Yasuhiro Ueno ◽  
Jiro Seki ◽  
Ikutaro Shimizu ◽  
Alexey P. Shershnev

1965 ◽  
Vol 22 (6) ◽  
pp. 1477-1489 ◽  
Author(s):  
H. T. Bilton ◽  
W. E. Ricker

Among 159 central British Columbia pink salmon that had been marked by removal of two fins as fry and had been recovered in commercial fisheries after one winter in the sea, the scales of about one-third showed a supplementary or "false" check near the centre of the scale, in addition to the single clear-cut annulus. This evidence from fish of known age confirms the prevailing opinion that such extra checks do not represent annuli, hence that the fish bearing them are in their second year of life rather than their third. Unmarked pink salmon from the same area, and some from southern British Columbia, had a generally similar incidence of supplementary checks. In both marked and unmarked fish the supplementary checks varied in distinctness from faint to quite clear. In a sample of scales of 14 double-fin marked chum salmon which were known to be in their 4th year, all fish had the expected 3 annuli, and 12 fish had a supplementary check inside the first annulus.


Trudy VNIRO ◽  
2020 ◽  
Vol 179 ◽  
pp. 90-102
Author(s):  
M. N. Gorokhov ◽  
V. V. Volobuev ◽  
I. S. Golovanov

There are two main areas of pacific salmon fishing in the Magadan region: Shelikhova Gulf and Tauiskaya Bay. The main fishing species is pink salmon in the region. Its share of total salmon catch by odd-year returns reaches 85 %. Data on the dynamics of escapement to the spawning grounds of pink salmon of the Shelikhova Gulf and Tauiskaya Bay are presented. The displacement of the level of spawning returns of pink salmon into the Shelihova Gulf with the simultaneous reduction of its returns to the Tauiskaya Bay is shown. Data on the dynamics of the fishing indicators of pink salmon for the two main fishing areas are provided. The Tauiskaya Bay as the main pink salmon fishery area loses its importance is shown. Graphical data on the escapement of producers pink salmon to the spawning grounds are presented and the optimal values of spawning escapements are estimated. Chum salmon is the second largest and most fishing species. Information on the dynamics of the number of returns, catch and escapement to the spawning grounds of chum salmon is given. The indicators of escapement to the spawning areas and their compliance with the optimal passes of salmon producers are analyzed. The issues of the dynamics of returns number, catch and the escapement to the spawning grounds of coho salmon producers are considered. The level of the escapement to the spawning areas is shown and the ratio of actual to optimal values of passes is estimated. The role of coho salmon as an object of industrial fishing and amateur fishing is shown. The extent of fishing press on individual groups of salmon populations is discussed. It is concluded that it is necessary to remove the main salmon fishery from the Tauiskaya Bay to the Shelikhova Gulf.


2019 ◽  
Vol 196 ◽  
pp. 182-192 ◽  
Author(s):  
V. P. Pogodin ◽  
S. I. Borzov ◽  
M. S. Myakishev ◽  
I. A. Varaksin ◽  
O. V. Zelennikov

Results of cherry salmon juveniles rearing at Reidovo fish farm on Iturup Island during two annual cycles of cultivation are analyzed. Different variants of the breeders selection, feeding, preventive treatment, and release were tested. The breeders were caught in the river mouth and near the fish farm. Mass mortality of young fish in the first and second years was avoided by decreasing of their density and other preventive measures. Minced fish was used as a food for them that is less expensive in compare with a combined fodder. The best diet for the second year of rearing was the minced pink salmon with the daily ration of 2 % of the juveniles body weight; it provided a significant decrease of mortality and enhanced their growth. After 2-year rearing, percentage of females, anadromous males, and dwarf males was 42.1, 36.3, and 21.6 %, respectively. Their weights were similar, though a group of fast-growing males was found among the dwarfs. The mass of ovaries varied from 13 to 46 mg in close dependence on females’ body weight (r = 0.81). Before the release, the ovaries of all females contained oocytes of similar size (varied in 2–4 times) at the final stage of previtellogenesis. Number of the oocytes per transverse section varied from 4.7 to 32.3, on average for 5 cuts and their diameter varied from 164.3 to 279.2 mm and did not correlate with the females body weight. The mass of dwarf males’ testes varied from 14 to 488 mg in dependence on their body weight (r = 0.78). The elder oocytes of females would mature in a year, and majority of dwarf males would reach the maturity in autumn of the current year.


1978 ◽  
Vol 56 (10) ◽  
pp. 2235-2238 ◽  
Author(s):  
J. C. Pearson ◽  
L. Margolis ◽  
N. P. Boyce

The metacercaria of Galactosomum phalacrocoracis (Trematoda: Heterophyidae), collected from Oncorhynchus gorbuscha (Walbaum) from coastal waters of British Columbia, is described.


1984 ◽  
Vol 41 (10) ◽  
pp. 1446-1453 ◽  
Author(s):  
William W. Smoker

Different stock dynamics result from genetic and nongenetic mechanisms of determination of maturation age of chum salmon (Oncorhynchus keta) in a model of interacting pink (O. gorbuscha) and chum salmon stocks. When the model is disturbed from equilibrium by low survival in one pink salmon line, the genetic mechanism (high heritability of maturation age) leads to biennial cycles of numbers of even-aged chums and of numbers of pinks, similar to observed cycles. The nongenetic mechanism (zero heritability of maturation age) results in a new equlibrium at which neither stock cycles. When one pink salmon line is completely removed the genetic mechanism leads to biennial cycles of abundance of even-aged chums; the nongenetic mechanism does not lead to such cycles. These effects persist at intermediate values of heritability of maturation age and in spite of stochastic variability. The model is an adaptation of the Ricker curve to two interacting stocks, the recruitment for each depending on the density of both.


1957 ◽  
Vol 14 (6) ◽  
pp. 815-830 ◽  
Author(s):  
W. S. Hoar ◽  
M. H. A. Keenleyside ◽  
R. G. Goodall

When given a choice between light and dark areas, schools of chum or pink salmon fry remain in the light, sockeye fry prefer the dark and coho fry show no marked preference for either. Newly emerged sockeye fry are the most strongly photonegative, remaining mostly under stones. Older sockeye fry move more into the light. Sockeye and coho smolts stay in the dark more than sockeye and coho underyearlings. Territorial and "escape" behaviour by fish in the experimental apparatus may obscure these reactions to light. Soon after emerging from the gravel, pink fry swim near the surface under low light intensity and retreat to deeper water in brighter light. Older pink fry seem indifferent to changing light. Recently emerged chum salmon fry do not respond in this way to changing illumination, although older fry tend to swim closer to the surface. This difference between pink and chum salmon fry may be related to differences in schooling behaviour and alarm responses of the two species.


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