New study on steelhead genes - "...up to 40% come from wild trout..."

cabezon

Sculpin Enterprises
#16
Curt's concern about the impact of bait fishing on preserving resident rainbows is likely to prove to be a sticking point for some. After all, salmon and steelhead eggs are a central part of the arsenal of many gear fishers, especially when fishing for hatchery salmon and steelhead. Expect to hear loud cries if a wide-spread ban on bait fishing is proposed; imagine if bait were outlawed on the Cowlitz.... [Actually, I can; I think that it would become a fabulous trout river - lots of bugs and productivity.]

Steve
 

Leroy Laviolet

Aint no nookie like chinookie
#19
“The genetic influences of hatchery fish on wild steelhead populations are still a concern,” Blouin said. “But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead.”

Could this mean that everyone may have to re-think there adamant hatred for hatchery programs and hatchery fish and dams ? Wouldn't that be a bitch if every yuppy blog had to drop that mantra ?????????????
 
#20
“The genetic influences of hatchery fish on wild steelhead populations are still a concern,” Blouin said. “But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead.”

Could this mean that everyone may have to re-think there adamant hatred for hatchery programs and hatchery fish ? Wouldn't that be a bitch if every yuppy blog had to drop that mantra ?????????????
That's one study from one river, most of the evidence points to hatchery fish having a negative impact on wild fish, there are other impacts aside from loss of fitness. I'm not saying that hatcheries don't have a place, but as they are run now they are not the answer.
 

Charles Sullivan

ignoring Rob Allen and Generic
#21
“The genetic influences of hatchery fish on wild steelhead populations are still a concern,” Blouin said. “But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead.”

Could this mean that everyone may have to re-think there adamant hatred for hatchery programs and hatchery fish and dams ? Wouldn't that be a bitch if every yuppy blog had to drop that mantra ?????????????
What would be a bitch is if someone actually asked the question whether our hatcheries actually resulted in more total fish, or if they actually had to answer the questions as to how much they cost and whether they are worth it.

Yuppie blogs?

Go Sox,
cds
 
#22
Excellent article and follow-ups ladies and gents..

Now if we could just get our policymakers to make positive change with these issues instead of the "we need more research data" repeat. :beathead:
 

yuhina

Tropical member
#23
I just glimpse through the original paper. below is my quick thoughts.


1) Hatchery fish is BAD.
This study was carried out in the Hood River, Oregon. Same research group found the hatchery fish decrease the wild run's fitness (life reproductive success) by more than 50% (Science paper, 2007?). Same river, same population. so what is the message? Gene exchange with hatchery fish is low (it depends on the hatchery program in the future), BUT gene exchange with hatchery fish still will cause the damage of 50% fitness loss on those hatchery offspring and also other unseen competition issues with the wild offspring.

2) 40% gene exchange (gene flow) with wild rainbow trout is the natural phenomenon of evolutionary consequence and processing. This is nothing new to biologists as Curt mentioned it earlier. The neat thing about this study is that they are the first time to quantify how many fish are doing it. Because of the location in the Hood river,they can capture every returning fish (below the dam) and do the grandparents pedigree analysis, that mean they can pin point their parents ID, grandparents ID by using the genetic markers (every individual has different genetic profile - just like fingerprints), and also this technique allow them to assign the unknown resources to the rainbow population (which they don't need to capture those fish).

3) 40% gene exchange with another residential trout could provide another buffer mechanism for steelhead, compare to other salmonoids (king salmon), those other species don't have this kind of luxury "buffering mechanism". This is the authors want to indicate, if everything being equal, Chinook and Coho will have more trouble than Steelhead, because they don't have residential population like those rainbows. So if some thing bad happen in their genetic property, steelhead "should" have better resistance because of those wild rainbows genes. What is a message? We got to take care of those rainbows too, they are a whole package deal.

4) For the genetic integrity point of view, I am not that worry about angling pressure on the residential trout. Instead, I will be more concern about how the hatchery program practice, and if there are any stocking rainbow/ cutthorat trout issues in this river.

Mark
 

Smalma

Active Member
#24
Richard -
]I agree that it would great to see more management changes/regulations responding to the importance of the resident trout.

However it may well be the largest obstacle to those changes continue to the apathy of the users - us. Over the last several decades there have several attempts to put in place regulations to accomplish more holistic management and in every case those attempts have been met with either yawns or opposition from the anglers of this State. While a few anglers are willing to lobby for spedific changes those efforts are typically limited to only those changes that directly effect their passionate interests - CnR of wild steelhead is about the only example.

I see no evidence that apathy is going to change. The only changes we are likely to see will probably be piece meal and will come from the efforts of a very small handful of individuals or the State (without much encouragement from the users).

Tight lines
Curt
 

Leroy Laviolet

Aint no nookie like chinookie
#25
That's one study from one river, most of the evidence points to hatchery fish having a negative impact on wild fish, there are other impacts aside from loss of fitness. I'm not saying that hatcheries don't have a place, but as they are run now they are not the answer.
I would agree they are not the answer, I also have my doubts they are half the problem many say they are- I love seeing the same guys who constantly jeer hatchery fish and hatchery programs, plaster the pictures with themselves and those same fish all over the web boards, Grip and grin,
"look at me and what i did , I hate these fish" should be the captions ... go figure -:rofl:

1) Hatchery fish is BAD.
This study was carried out in the Hood River, Oregon. Same research group found the hatchery fish decrease the wild run's fitness (life reproductive success) by more than 50%. Same river, same population. so what is the message here? Mark
Do you have the source of this? different study correct, could you post it?
 

yuhina

Tropical member
#26
Dramatic drops in the reproduction rates of released hatchery fish were previously reported in a 2007 issue of the journal Science. The study noted the effects could be explained by a natural selection that favors characteristics useful in a sheltered, predator-free artificial environment over those necessary in the more hostile natural world. Of the large numbers of eggs laid by the released mothers during spawning, only a small fraction ever reached adulthood—the few that were best suited for survival in wild conditions.

An article talk about those series of research: LINK

http://www.scientificamerican.com/article.cfm?id=fish-hatchery-silverhead-salmon-genetics

Araki and his colleagues looked at the Hood River steelhead supplementation program in Oregon and found that trout fry raised by two hatchery-reared parents had just 37 percent of the reproductive success of those with two wild-born parents, even though both sets of offspring were born in wild waters.

Science abstract: http://www.sciencemag.org/content/318/5847/100.abstract
 

TomB

Active Member
#28
“The genetic influences of hatchery fish on wild steelhead populations are still a concern,” Blouin said. “But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead.”

Could this mean that everyone may have to re-think there adamant hatred for hatchery programs and hatchery fish and dams ? Wouldn't that be a bitch if every yuppy blog had to drop that mantra ?????????????


Leroy- The study's authors say in their discussion section that the contribution of genetic material by wild resident fish to steelhead populations may dilute the negative effects of anadromous hatchery fish spawning in the wild (i.e. if there are anadromous wild and hatchery fish, and you add more wild resident fish, the total % of wild goes up)...their results DO NOT say anything about hatchery fish being more fit than previously thought at reproducing in the wild. In fact, the same group used the same dataset to analyze the fitness of hatchery fish and their descendants spawning in the wild, and found that they have much lower fitness than wild fish...see this link

http://www.sciencemag.org/content/318/5847/100.full

I have no idea where or how you arrived at the conclusions you did above, but they are way off base. The article says nothing about dams, and their research program reinforces what we already know about the poor fitness of hatchery fish spawning in the wild. You might be well-served by actually reading such articles before deciding what their conclusions and implications are. Either that or risk sounding misinformed or biased.
 
#30
" The contribution of genetic material by wild resident fish to wild steelhead populations MAY dilute the negative effects of anadromous hatchery fish spawing in the wild"

"MAY" being the definative word in that sentence.