Hundreds Of Millions Of Salmon Feared Dead On US West Coast due to Fukushima nuclear

derwoodii

Senior Member.
Hundreds of millions of Pacific salmon are missing, presumed dead, along the US west coast amid fears that ocean life are dying in “stunning numbers” following the Fukushima disaster in Japan. According to The California Department of Fish and Wildlife, preliminary data from the Sacramento River indicates that salmon runs have dropped to record low levels.
http://yournewswire.com/millions-salmon-dead-west-coast/
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The claim is 100's of millions salmon feared dead due to Fukushima. The picture provided is from Adams river British Columbia 2012 & the picture source is 2010 after salmon run upstream they spawn & die.. and the numbers a bit inflated as likely 10 to 100.000 thousand not millions.

http://www.amusingplanet.com/2012/05/adams-river-salmon-run.html

dead-salmon-west-coast-678x381.jpg

i thought this be easy debunk,, well the picture part was but its get tricky drawing in complex cause and effect upon salmon population. It seems that the fish numbers have been dropping over past 30 years & 2016 is bad season but no claim is made by authority that cause is Fukushima fall out & thats its most likely warming oceans climate change over fishing or other ocean environmental impact..



Browse: Home / 2017 / March / Overview of the 2016 Salmon Season & Outlook for 2017
Overview of the 2016 Salmon Season & Outlook for 2017

This entry was posted in Watershed Watch Activities and tagged 2016 Salmon Re-cap; fisheries. Filed In: Fisheries Management. Posted byTrish Hall on March 3, 2017

prepared by Greg Taylor, Fisheries Advisor

Summary:

  • Warm ocean conditions and variable freshwater conditions led to reduced salmon returns coastwide
  • Reports by DFO’s Conservation and Protection Branch indicate high levels of non-compliance in several important fisheries
  • The level of core stock assessment funding for salmon reached an all-time low in 2016, leaving critical gaps in the monitoring of our salmon runs
  • Recent environmental conditions that are detrimental to salmon production will likely reverberate through 2017 – 2019, suggesting returns will continue to be both highly variable and unpredictable
.....
Scientists first detected what became popularly known as “the blob”1 in 2013. This vast area of abnormally warm water grew to around nine million square kilometers. It slowly dissipated during 2015, but was followed by a powerful El Niño event lasting from 2015 through much of 2016.

As a result of the abnormal ocean conditions present from 2014 through 2016, warm waters dominated the North Pacific ecosystem, ushering in new predators and unusual zooplankton. Many salmon entering the marine environment in 2014 did not fare well, with some—like some interior Fraser sockeye and stream-type Fraser chinook runs—returning in very low numbers.
https://www.watershed-watch.org/2017/03/recap-of-2016-bc-salmon-fisheries/
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Once again, testing finds Alaska seafood free of Fukushima radiation
  • Published January 10
For the third consecutive year, tests have found no radioactivity in Alaska seafood stemming from the 2011 tsunami and nuclear disaster in Fukushima, Japan, state officials announced Monday.

The Alaska Department of Environmental Conservation said in a statement that seafood samples from Alaska waters in 2016 tested negative for three Fukushima-related radioactive isotopes: iodine-131, cesium-134 and cesium-137. The findings for the tested species — including king, chum, sockeye and pink salmon, as well as halibut, pollock, sablefish, herring and Pacific cod — matched those from 2014 and 2015.

....
Although the FDA already analyzes foreign and domestic foods in the U.S. for radioactive isotopes, Brewer said the state has received "a lot of concern from the community" seeking data for seafood in Alaska waters.

https://www.adn.com/alaska-news/sci...s-alaska-seafood-free-of-fukushima-radiation/
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Declining Salmon numbers is a worldwide phenomena. Here's a 2012 report from The Scottish Salmon and Trout Conservation body...
http://www.salmon-troutscotland.org/salmon_population_trends.asp
The trend has been almost inexorably downwards since the early 1970s with the ICES data indicating a severe fall from the late 1980s. The decline in fish numbers reflects a long-term and substantial reduction in the marine survival of juvenile salmon – before they return as adults (after one or more years at sea) to their rivers of origin. The Scottish Government's Fisheries Research Services has closely monitored the marine survival of Scottish salmon since 1964. In the 1960s 25 % to 30 % (sometimes more, for example on the River North Esk, where it could be as high as 40 % to 50 %) of outgoing juvenile fish (smolts) would survive. Since then the trend has been downwards and now 10 % or less survive. The decrease in marine survival is almost certainly related to climate change. Todd et al (2008) detail how "1992–2006 has seen widespread sea surface temperature warming of the NE Atlantic, including the foraging areas exploited by salmon of southern European origin". During this period sea surface temperatures in the North Atlantic rose by an average of 0.5 to 1.5oC per decade, affecting the availability and abundance of the prey species which maturing salmon feed on; Todd et al note a consensus that "large–scale, climate-driven biogeographic shifts in the epipelagic ecosystem are likely to have exerted substantial bottom-up impacts on generalist predators high in the food web (e.g. Richardson & Schoeman, 2004; Frederiksen et al, 2006), including Atlantic salmon" and "given that Atlantic salmon spend most of their time in surface waters .... and that the preferred oceanic habitat of post–smolts in the subpolar gyre lies only within a narrow temperature range (Friedland et al, 1993; Friedland, 1998; Jonsson & Jonsson, 2004), such rates of ocean surface warming are very likely to have marked and possibly detrimental consequences for growth and/or survivorship of salmon at sea". Further research into the reasons for the decline in marine survival is currently a major international priority through NASCO's £4.5M SALSEA-Merge project. There is no doubt however that decreasing marine survival is simply a matter of fact and that it is now by far the most critical factor affecting Atlantic salmon fisheries.
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Similar declines are noted for Salmon in the Baltic...
https://www.google.co.uk/url?sa=t&r...f95rxh8pA&sig2=mEHMEAIuEtgzdbCi4g4MEA&cad=rja
In the Baltic today fewer than 10 percent of the young salmon fry are the
offspring of “wild” salmon, while 90 percent of the offspring are produced in
hatcheries (International Baltic Sea Fisheries Commission (IBSFC), 2000). The
percentage of “wild” offspring dropped from more than 30 percent in 1979
to below 20 percent in 1985.
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[Broken External Image]:http://b-i.forbesimg.com/monteburke/files/2013/06/pfa-chart-with-notes-dfo-2.jpeg
Graph of Atlantic Salmon population since 1970

So its not just the Pacific salmon that is in decline, the same trend is happening in populations such as the Baltic and North Atlantic stocks which are not connected and unrelated to the Pacific stocks.

There are a number of factors which are claimed as causes for this including the spread of sea lice and other parasites and diseases from farmed populations to wild population...
http://rspb.royalsocietypublishing.org/content/276/1672/3385.short
Floating sea cages (or net pens) allow free movement of pathogens between farmed and wild finfish. Modern mollusc culture similarly exposes farm stock to natural pathogens, but is at similar densities as found in nature, for example, in mussel and oyster beds. However, even at low farm stocking densities, sea-cage culture holds fishes for months in the same location at high host densities; a situation that does not occur in nature for such long time periods (Bergh 2007). These conditions facilitate disease and parasite transmission within the farm (Murray & Peeler 2005). Thus, should pathogens from wild hosts infest a farm, their population may grow exponentially and release the pathogens back into the same environment (Murray 2008). Depending on how the pathogen finds new hosts, the behaviour and ecology of the wild hosts and local hydrographic conditions, this may or may not have a significant impact on the wild fish populations. The sea lice interaction between aquaculture and wild fish stocks has important implications for the management and viability of both resources (Rosenberg 2008).

The best-studied example of this interaction has been the epidemiology of sea lice, namely, the ectoparasitic copepod crustaceans Lepeophtheirus salmonis (Krøyer) and several species of the genus Caligus; recently reviewed by Costello (2006). Their life cycle consists of non-feeding planktonic larvae (nauplii), an infective planktonic copepodite,1 immature ‘chalimus’ embedded on the host skin and mobile pre-adults and adults that move freely over the host skin. Sea lice are the most pathogenic parasite in salmon farming and may cost the industry €300 million (US$480 million) a year and 6 per cent of product value (Costello 2009). The planktonic larvae and mobile adults infest farmed fishes from natural populations and adjacent farms, but their progeny are then released from the net pens into the surrounding environment where they may infect wild hosts.
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Accidental or deliberate introduction of 'alien' species into the ecosystem resulting in predation or competition for resources...
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2664.2000.00538.x/full

The impact of water course management in rivers and salmon streams...
http://www.snh.org.uk/publications/on-line/advisorynotes/20/20.htm
Farmers should consult SEPA prior to abstracting water for irrigation, since an abstraction licence may be needed. Farmers should also be encouraged to abstract as little water as possible during low flow conditions, thus allowing an adequate 'hands off discharge. This is particularly true for salmon spawning rivers where an adequate intragravel flow is necessary to supply eggs and fry with oxygenated water and to remove metabolites
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Over fishing...
http://www.pnas.org/content/106/Supplement_1/9987.short
Human harvest of phenotypically desirable animals from wild populations imposes selection that can reduce the frequencies of those desirable phenotypes. Hunting and fishing contrast with agricultural and aquacultural practices in which the most desirable animals are typically bred with the specific goal of increasing the frequency of desirable phenotypes. We consider the potential effects of harvest on the genetics and sustainability of wild populations. We also consider how harvesting could affect the mating system and thereby modify sexual selection in a way that might affect recruitment. Determining whether phenotypic changes in harvested populations are due to evolution, rather than phenotypic plasticity or environmental variation, has been problematic. Nevertheless, it is likely that some undesirable changes observed over time in exploited populations (e.g., reduced body size, earlier sexual maturity, reduced antler size, etc.) are due to selection against desirable phenotypes—a process we call “unnatural” selection. Evolution brought about by human harvest might greatly increase the time required for over-harvested populations to recover once harvest is curtailed because harvesting often creates strong selection differentials, whereas curtailing harvest will often result in less intense selection in the opposing direction.
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...and rising sea temperatures effecting the whole food chain and eco-system...
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2419.1998.00047.x/full
The survival of two Atlantic salmon stocks that inhabit rivers confluent with the North Sea was examined in respect to historical distributions of sea surface water temperatures. The rivers Figgjo and North Esk are relatively small salmon rivers in southern Norway and eastern Scotland, respectively. Wild salmon smolts have been tagged in these rivers since 1965. Tag returns were used to evaluate the survival of salmon in the North Sea. Survival rates of one-sea-winter (1SW) and 2SW fish were correlated within stocks, as well as between stocks. Survival rates were compared with the areal extent of thermal habitat in the north-eastern Atlantic Ocean. A positive correlation was found between the area of 8–10°C water in May and the survival of salmon. A reciprocal negative correlation was also found between survival and 5–7°C water in the same month. An analysis of sea surface temperature distributions for periods of good vs. poor salmon survival showed that when cool surface waters dominate the Norwegian coast and North Sea during May, salmon survival has been poor. Conversely, when the 8°C isotherm has extended northward along the Norwegian coast during May, survival has been good. The effect of water temperature distributions on the growth of postsmolts and other survival factors are discussed.
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All of which are impacting the population of Salmon worldwide, and thus shows that Fukushima is not a significant factor, if it is a factor at all.
 
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