Possible Causes and Effects of Shifts in Trends of Abundance in Pink Salmon of Southern Sakhalin and Iturup Islands
نویسندگان
چکیده
Data on the abundance of spawning pink salmon (Oncorhynchus gorbuscha) are presented for rivers of southern Sakhalin Island and Iturup Island. Fluctuations in abundance are more dependent on marine survival than on the abundance of fry migrating downstream. This is explained by the favorable spawning conditions in small rivers with dense aggregations on the spawning grounds. We found stable long-term trends in changes in abundance, fish length and the seasonal dynamics of spawning migrations. These trends suggest an important role for climatic-oceanological cyclical processes in pink salmon stock dynamics. All correspondence should be addressed to A. Kaev. e-mail: [email protected] Possible Causes and Effects of Shifts in Trends of Abundance in Pink Salmon of Southern Sakhalin and Iturup Islands Alexander M. Kaev, Alexander A. Antonov, Vladimir M. Chupakhin, and Vyacheslav A. Rudnev Sakhalin Research Institute of Fisheries and Oceanography (SakhNIRO), 196 Komsomolskaya Street, Yuzhno-Sakhalinsk 693016, Russia
منابع مشابه
Changing trends in the abundance and biomass of cyanobacteria in the southern part of the Caspian Sea in 2009 (The stretch between Tonekabon and Amirabad)
Changes in abundance and biomass of cyanobacteria have been studied in the southern part of the Caspian Sea (the stretch between Tonekabon and Amirabad) in four seasons (spring, summer, autumn, winter) in which samples were taken from five depths of 5, 10, 20, 50 and 100 meters in the stations of Tonekabon, Noushahr, Babolsar and Amirabad. Samples were fixed in formalin (2-2.5%) before transfer...
متن کاملChanging trends in the abundance and biomass of cyanobacteria in the southern part of the Caspian Sea in 2009 (The stretch between Tonekabon and Amirabad)
Changes in abundance and biomass of cyanobacteria have been studied in the southern part of the Caspian Sea (the stretch between Tonekabon and Amirabad) in four seasons (spring, summer, autumn, winter) in which samples were taken from five depths of 5, 10, 20, 50 and 100 meters in the stations of Tonekabon, Noushahr, Babolsar and Amirabad. Samples were fixed in formalin (2-2.5%) before transfer...
متن کاملClimate, Growth and Population Dynamics of Yukon River Chinook Salmon
Harvests of Yukon Chinook salmon increased in the mid-1970s, then declined during 1998 to 2007 in response to fewer returning salmon. We examined annual growth of age-1.3 and age-1.4 Yukon Chinook salmon scales, 1965–2004, and tested the hypothesis that shifts in Chinook salmon abundance were related to annual growth at sea. Annual scale growth trends were not significantly correlated with salm...
متن کاملAbundance Dynamics of Pink Salmon, Oncorhynchus gorbuscha, as a Structured Process Determined by Many Factors
Despite the fact that pink salmon is a fish species with a short-cycle life span, its stock abundance dynamics exhibit features typical of common pelagic fish species with an average life-cycle duration. Interchanging periods of high and low pink salmon abundance levels relate to positive and negative stock abundance trends inherent for major regional groups, Asian and American parts of aggrega...
متن کاملRegional-Scale Declines in Productivity of Pink and Chum Salmon Stocks in Western North America
Sockeye salmon (Oncorhynchus nerka) stocks throughout the southern part of their North American range have experienced declines in productivity over the past two decades. In this study, we tested the hypothesis that pink (O. gorbuscha) and chum (O. keta) salmon stocks have also experienced recent declines in productivity by investigating temporal and spatial trends in productivity of 99 wild No...
متن کامل