Hatchery salmon may need to be capped

[Derby]

Nations around the Pacific Ocean may have to cap the number of hatchery salmon they release if sockeye salmon runs are to return to sustainable levels, according to a new study.
http://www.vancouversun.com/More+news+wild+sockeye/10938957/story.html

 

[Cuba Libre]

That stands to reason if you look at the production of pinks, chums and to a lesser extent coho and chinook being produced by Japan, Russia , Alaska, BC and the rest of the PNW. The ocean can only support so many mouths-- but we dont know what that level is.

 

[agentaqua]

The other issue to deal with - in addition to just looking at numbers overall - is species-specific numbers - and how a bump in one species is to either the benefit or detriment to another.

Looks like pinks and sockeye are competitors for each other wrt pumping out juvies and negative species-specific density-dependent interactions. looks like juvie pinks often feed the larger coho juvies - as an example of a so-called "positive" species-specific density interaction (positive for the coho, at least).

Also - not every hatchery has either good water quality; or close, adjacent outplanting environment for every species - and numbers of available broodstock are often also an issue. Length of time reared and fed can have also quite an impact on the success of hatcheries and outplanting.

Just pumping out juvies and hoping for the best is - at the least - and ineffective strategy as to understanding what success a hatchery may or may not have had. The only real way to do that is to tag (e.g. PIT tags, etc.) and have at least a couple of strategies wrt feeding and time of release - then do the science.

The unfortunate reality is that most hatcheries are severely underfunded, and the volunteers are overworked. So very few do this kind of strategic planning and benchmarking of effectiveness. Almost no hatcheries are co-ordinated in a larger strategy of ocean-wide stock assistance. It's long overdue. Thanks for posting this Derby.

 

[OldBlackDog]

[h=1]More bad news for B.C.’s wild sockeye[/h]

Nations around the Pacific Ocean may have to cap the number of hatchery salmon they release if sockeye salmon runs are to return to sustainable levels, according to a new study.
Record high numbers of pink salmon in the North Pacific coincided with the disastrously small 2009 Fraser River sockeye return, while the unexpectedly large 2010 sockeye return interacted with 40-per-cent fewer pinks, said Brendan Connors, co-author of the article published by the Canadian Journal of Fisheries and Aquatic Sciences.
The findings have implications for fisheries management and hatchery programs in Russia and Alaska that produce most of the five billion hatchery fish released into the Pacific each year.
“ ... Even though overall abundance of wild pink salmon has been exceptionally high during the past 30 years, hatchery operators have proposed substantial increases in hatchery pink salmon in Prince William Sound, Kodiak, Yakutat, Southeast Alaska, and Russia,” the authors write.
But there has been little cooperation between nations about the release of hatchery salmon, even in the face of evidence that large-scale hatchery programs can have far-reaching effects, according to fisheries scientist Randall Peterman, a professor emeritus at SFU.
“Getting an international agreement on who should get how much of the ocean’s carrying capacity for salmon is a major policy stumbling block, despite what is clear in the scientific realm,” he said.
According to the new research, food competition between pinks and sockeye has led to slower growth, delayed maturation and spawning, and lower survival rates for B.C.’s iconic fish.
Sockeye that mature later may return to freshwater and spawn successfully, but spending an extra year at sea means they have a better chance of being eaten by predators, said Connors, an ecologist and adjunct professor at Simon Fraser University.
“We also find that the sockeye are smaller when they are in competition and that reduces the number of eggs produced by females,” he said.
Observed increases in the number of pinks were predicted to reduce Fraser sockeye abundance by 67 per cent, Connors said.
The four leading hypotheses presented to the Cohen Commission convened to explain the decline of the Fraser River sockeye were: climate-related changes to ocean conditions, allowing too many fish onto spawning grounds, salmon aquaculture and interactions with pink salmon.
“When we looked at all four of these things together around the time of the commission, the one that had the strongest support was the competition with pink salmon,” he said. “And in years when sockeye salmon migrated past a large number of salmon farms that negative relationship was even stronger.”
Peak pink abundance — fuelled in part by the annual release of up to 1.4 billion hatchery pinks — is linked to the decline of 36 of 38 sockeye populations from Washington State to Alaska, according to Connors. Pink salmon eat many of the same foods as sockeye, especially squid and plankton, and are known to be more flexible and opportunistic about their diet than sockeye. By switching prey, the pinks may be changing the entire food web and reducing the abundance of the sockeye’s favourite foods.
Because populations of pink salmon peak every second year — in odd years on the south coast — the effect of their abundance on other fish and other sea creatures is relatively easy to observe, said Connors, who penned the study with Seattle-based fishery scientist Greg Ruggerone.
Past research has linked pink abundance to declines in Bristol Bay sockeye, chinook salmon released in Puget Sound and even seabirds such as kittiwakes and puffins in Alaska.
“We are at a point when it makes sense to have a conversation about hatchery programs while conditions in the Pacific Ocean are fairly favourable, especially in the north,” Connors said. “If that changes we could suddenly have a whole lot of fish competing for even fewer resources.”
rshore@vancouversun.com
© Copyright (c) The Vancouver Sun

 

[fogged in]

I'm all for no Pink Salmon Hatcheries!
I find them to be nothing but a nuisance...only come in my boat if I need some halibut bait...and I know many like them, both for the sport and eating...each to his own.
Not sure now Pinks impact Sockeye though, as Pinks do not eat Plankton?
Perhaps I am missing something here.

 

[searun]

Starting to be some evidence to support releasing fewer numbers of Chinook smolts, but better quality. There are large differences in outcomes between Conuma and Robertson. Clearly Robertson puts out 2/3 more smolts and gets about 2/3 as many returning adults....PROBLEM. More isn't always better....or put another way quality over quantity in this current ocean regime may be the better strategy.

 

[Aces]

You still need a good number of all species of salmon that spawn at different times to die in the rivers to keep the nutrient level up.

 

[searun]

You still need a good number of all species of salmon that spawn at different times to die in the rivers to keep the nutrient level up.

Absolutely, that's why I didn't understand the comment about pinks. All salmon have a purpose in the river, and bring something to the table. Its all about striking a natural balance that nature can support.

 

[steelmadness]

Pink and sockeye life cycles and spawning habits are so very different. Hard to see them competing.

 

[Stoisy]

Competition for food has nothing to with timing of spawning - the ocean has a maximum capacity of salmon that it can support and loading it with an unnaturally high number of "artificial" salmon will reduce the resources for other species. With Pinks having more adaptability in their diet they will prey on the food that Sockeye consume when their natural food source is low.

Checkout DamNation on Netflix for some good info on the effects of hatcheries. The science supports that hatcheries are bad for wild populations, yes it reduces some angling pressure, but the negatives far outweigh that.

 

[agentaqua]

Some other threads on this forum about this topic that may be of interest:

http://www.sportfishingbc.com/forum...tat-Restoration-Compared-T&highlight=hatchery
http://www.sportfishingbc.com/forum...fectiveness-Of-Habitat-Restoration-Compared-T
http://www.sportfishingbc.com/forum...-impact-research-in-Alaska&highlight=hatchery

 

[OldBlackDog]

This is the real problem.
5 Billion fish.


The findings have implications for fisheries management and hatchery programs in Russia and Alaska that produce most of the five billion hatchery fish released into the Pacific each year.
“ ... Even though overall abundance of wild pink salmon has been exceptionally high during the past 30 years, hatchery operators have proposed substantial increases in hatchery pink salmon in Prince William Sound, Kodiak, Yakutat, Southeast Alaska, and Russia,” the authors write.
But there has been little cooperation between nations about the release of hatchery salmon, even in the face of evidence that large-scale hatchery programs can have far-reaching effects, according to fisheries scientist Randall Peterman, a professor emeritus at SFU.
“Getting an international agreement on who should get how much of the ocean’s carrying capacity for salmon is a major policy stumbling block, despite what is clear in the scientific realm,” he said.

It is an international problem and needs to be delt with by governments.

B.C. Has been cutting back production for years.
At the rate they are cutting back on coho and no longer clipping, it will not be long until you will not be able to retain them.

 

[steelmadness]

Competition for food has nothing to with timing of spawning - the ocean has a maximum capacity of salmon that it can support and loading it with an unnaturally high number of "artificial" salmon will reduce the resources for other species. With Pinks having more adaptability in their diet they will prey on the food that Sockeye consume when their natural food source is low.

Checkout DamNation on Netflix for some good info on the effects of hatcheries. The science supports that hatcheries are bad for wild populations, yes it reduces some angling pressure, but the negatives far outweigh that.

The differences between the two species are so much more than simple run timing. I didn't think I'd have to elaborate......

 

[agentaqua]

Ya - the competition isn't really in the FW - for spawning competition. It's in the marine environment - particularly between juvies/sub-adults:

http://www.richardbeamish.com/uploads/1/6/0/0/16007202/1284canada.pdf
http://www.nrcresearchpress.com/doi/abs/10.1139/cjfas-2014-0134#.VTEW8dh0x7g
http://www.bioone.org/doi/pdf/10.1080/19425120.2013.831002
https://www.pices.int/publications/presentations/PICES_13/PICES_13_S2/Nielsen_S2.pdf
http://www.sfu.ca/grow/science/resources/1273768738.pdf

More bad news for B.C.’s wild sockeye
Pink salmon populations augmented by hatchery programs hurt sockeye returns, study finds
By Randy Shore, Vancouver Sun April 1, 2015

Food competition between pinks and sockeye has led to slower growth, delayed maturation and spawning, and lower survival rates for B.C.’s iconic fish, a new study finds.

Photograph by: JONATHAN HAYWARD , THE CANADIAN PRESS


Nations around the Pacific Ocean may have to cap the number of hatchery salmon they release if sockeye salmon runs are to return to sustainable levels, according to a new study.

Record high numbers of pink salmon in the North Pacific coincided with the disastrously small 2009 Fraser River sockeye return, while the unexpectedly large 2010 sockeye return interacted with 40-per-cent fewer pinks, said Brendan Connors, co-author of the article published by the Canadian Journal of Fisheries and Aquatic Sciences.

The findings have implications for fisheries management and hatchery programs in Russia and Alaska that produce most of the five billion hatchery fish released into the Pacific each year.

“ ... Even though overall abundance of wild pink salmon has been exceptionally high during the past 30 years, hatchery operators have proposed substantial increases in hatchery pink salmon in Prince William Sound, Kodiak, Yakutat, Southeast Alaska, and Russia,” the authors write.

But there has been little cooperation between nations about the release of hatchery salmon, even in the face of evidence that large-scale hatchery programs can have far-reaching effects, according to fisheries scientist Randall Peterman, a professor emeritus at SFU.

“Getting an international agreement on who should get how much of the ocean’s carrying capacity for salmon is a major policy stumbling block, despite what is clear in the scientific realm,” he said.

According to the new research, food competition between pinks and sockeye has led to slower growth, delayed maturation and spawning, and lower survival rates for B.C.’s iconic fish.

Sockeye that mature later may return to freshwater and spawn successfully, but spending an extra year at sea means they have a better chance of being eaten by predators, said Connors, an ecologist and adjunct professor at Simon Fraser University.

“We also find that the sockeye are smaller when they are in competition and that reduces the number of eggs produced by females,” he said.

Observed increases in the number of pinks were predicted to reduce Fraser sockeye abundance by 67 per cent, Connors said.

The four leading hypotheses presented to the Cohen Commission convened to explain the decline of the Fraser River sockeye were: climate-related changes to ocean conditions, allowing too many fish onto spawning grounds, salmon aquaculture and interactions with pink salmon.

“When we looked at all four of these things together around the time of the commission, the one that had the strongest support was the competition with pink salmon,” he said. “And in years when sockeye salmon migrated past a large number of salmon farms that negative relationship was even stronger.”

Peak pink abundance — fuelled in part by the annual release of up to 1.4 billion hatchery pinks — is linked to the decline of 36 of 38 sockeye populations from Washington State to Alaska, according to Connors. Pink salmon eat many of the same foods as sockeye, especially squid and plankton, and are known to be more flexible and opportunistic about their diet than sockeye. By switching prey, the pinks may be changing the entire food web and reducing the abundance of the sockeye’s favourite foods.

Because populations of pink salmon peak every second year — in odd years on the south coast — the effect of their abundance on other fish and other sea creatures is relatively easy to observe, said Connors, who penned the study with Seattle-based fishery scientist Greg Ruggerone.

Past research has linked pink abundance to declines in Bristol Bay sockeye, chinook salmon released in Puget Sound and even seabirds such as kittiwakes and puffins in Alaska.

“We are at a point when it makes sense to have a conversation about hatchery programs while conditions in the Pacific Ocean are fairly favourable, especially in the north,” Connors said. “If that changes we could suddenly have a whole lot of fish competing for even fewer resources.”

rshore@vancouversun.com

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