what-to-do-with-fish-when-the-river-runs-dry
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UkeeDreamin
Well-Known Member
Very slippery slope to intervene in natural ecosystems unless you know for a fact productivity is being affected. Many “stranded” or “isolated“ pools are actually fully connected to the groundwater and hyporheic (subsurface stream) flow - which maintain acceptable DO and temp. The natural processes that kill a high percentage of salmonids is also part of the critical natural selection that ensures the strongest individuals and those best adapted to their specific stream. In the PNW, our salmon and trout spp have evolved to live in river and stream ecosystems that have extremities of flows - from the most severe floods to extended periods of drought. Making beneficial use of isolated pools and, at times, even burrowing down into the substrate itself, are strategies salmonids have evolved.
Other issues that are rarely, if ever, considered include competition, crowding and displacement impacts to the population already utilizing the ”relocation habitat” as well as timing/life-history issues (eg moving fish in fall after their migration period to overwintering habitats). The old saying “out of the frying pan but into the fire” comes to mind.
I get this issue tugs at peoples heart strings but, just like a predator taking down its prey, nature is brutal but it works when things are in balance. If there is data showing a population is at risk AND stranding has been ID’d as a significant source of unnatural mortality would be exceptions to my opinions above.
Cheers!
Ukee
Other issues that are rarely, if ever, considered include competition, crowding and displacement impacts to the population already utilizing the ”relocation habitat” as well as timing/life-history issues (eg moving fish in fall after their migration period to overwintering habitats). The old saying “out of the frying pan but into the fire” comes to mind.
I get this issue tugs at peoples heart strings but, just like a predator taking down its prey, nature is brutal but it works when things are in balance. If there is data showing a population is at risk AND stranding has been ID’d as a significant source of unnatural mortality would be exceptions to my opinions above.
Cheers!
Ukee
I agree Ukee, often best to leave them alone. I have been involved in a few of these "rescues" and imo, the fish being transferred were under far greater stress from the intervention. Another issue is often the water temperatures are considerably different from where the fish are stranded to where the are transported, resulting in mortalities.
UkeeDreamin
Well-Known Member
Thanks Agentaqua, an important issue as salmon conservation is top of mind for many in PNW and thus folks want to do their part. No shortage of impacts these days but I’ve always felt the ones that result from honest, good intentions are the most discouraging.
Cheers!
Ukee
Cheers!
Ukee
The reality is that the world that salmon evolved in has changed to the point at where they sometimes could use a hand finding appropriate conditions. Droughts and poor conditions have always existed however the landscape is now so altered that it no longer functions as it did 100 years ago. Every watershed has had its water flow and habitat degraded to where there is no longer a slow release of water into streams and the forest that once protected and shaded these areas is gone. The idea that we shouldn't help wild fish when their habitat has been altered by us seems crazy when so many people think hatcheries are a solution to the problem. Leaving fish to die in a stream that is full of gravels from erosion is not natural and the reality is most every stream is altered by erosion from logging. It isn't hurting evolution by allowing the weak to survive because in a low water high temp situation the weak most likely have already perished. Water flows fluctuate so fast now that stranding's happen so quickly that I have seen them happen within in a day. I will continue to help them when I see a need for it. If you don't agree with helping out at adolescent stage then why help at adult stage. A pinniped taking out adults at a choke point caused by low water is no different than the easy picking of any other predator in a human caused tiny pool in some crick. Easy to sit on a computer and judge some one else's efforts but those buckets saved more fish then any letter getting dusty at dfo's office.
Bryan Allen
Well-Known Member
As someone that has 20 years experience being involved in fry salvage and fry rescue on the Mainland and Vancouver Island I find the article overly simplistic. Is there a place for salvage and rescue ???? Absolutely ! If humans were removed from the picture and the habitat conditions were stable , then maybe we could walk away from that part of the salmon's life cycle. But we ARE involved. Take a look a the effects of logging on small and large stream flows. Urbanization too. Flows are diverted away from the natural steam corridors reducing volumes and introducing toxins that destroy water quality. Agriculture ????? Yes-- irrigation water pumped from the ground or diverted to broccoli beds can be lethal to fish in very short order. And the list goes on. There is one volunteer society on Vancouver Island , Fanny Bay Enhancement Society, that has rescued approx. 1/2 million salmon and trout fry over the years from streams in the Baynes Sound area of the east coast of the Island. Because of the problems listed above, plus poor engineering on parts of Highway 19 , large sections of some of the stream beds go dry in the summer. When that happens, out comes the gumboots and fry nets. The fish are taken back to the FBES holding facility and reared until the streams recharges. This program is only one of many others that assist the fish that our treatment of BC streams has screwed up. And for the comment that fish can survive out of water by burrowing into the gravel-- dont count on it. Anyone who has done enhancement on dried stream beds will tell you that at times the smell of rotting fish can very powerful. Is there a wrong way to do fry salvage ? Sure. In the video the lady is chasing fry with a pole net where there is prime habitat under root wads and well vegetated stream banks. The groups I worked with would not try to remove fish from that habitat. But the section was most probably just part of the photo op for the story. While scrutiny of human efforts that alter the natural regime or affect the natural inhabitants is always a good idea, I don't feel this article presented a balance picture. (BTW-- if you want to see how some fry can survive being buried for short periods, Google "The Man Who Digs For Fish" )
IronNoggin
Well-Known Member
BINGO!
Been watching this thread a bit, and was somewhat surprised by the comments from the armchair biologists.
I ran the Salmon Fry Salvage Program in the Alberni Valley for a series of overly hot summers.
Stranded coho, steelhead and chinook fry were captured bu a series of seines sweeps, followed by a final sweep with a backpack electroshocker in most cases. That process also allowed a regression analysis at the same time to help us understand the level of each species use of varied flowing waters. Extreme care was taken with the handling of the fish, from oxygenated water in the transport tanks, to exacting temperature regimes in the same as well as habituating slowly to recipient waters.
We are talking hundreds of thousands of fry here.
And in the subsequent years, when those little creeks and rivers once again teemed with adult returners, we all felt a sense of pride in what we had done to help insure that result.
In this day and age of increasingly depressed salmon populations, they need all the help they can get.
That being said, the process should be conducted professionally by those with hands on experience IMO.
It did, and it can make a hell of a difference.
Reality.
Nog
Exactly this.
It seems a few have very black and white perspectives on this topic. For me it is a yet another grey area, and the numerous points to consider have already been raised by a few both "pro" and "con" posters, along with a few previously mentioned in the article. I really don't think that by raising these important points one needs to label, dismiss & invalidate dissenting opinions as "armchair biologists" since they differ from one's own opinions. I think this is an important issue and all these issues need to be considered before reacting using preconceived assumptions about the survivability of the trapped fry. It is irresponsible to me to react w/o thinking about these things, and I think both sides have valid points to offer. And I think we all care about the fish at the core of this debate, as well.
UkeeDreamin
Well-Known Member
So sad some folks become bitter, spiteful old men ... tit for tat on the laughing emojis, so mature!
Anyway, as I approach my 35th year as a professional fisheries biologist, the past 25+ solely on the conservation and protection of freshwater salmonid habitat and populations, I am no armchair bio and would wager I’ve spent more days on stream specifically studying, monitoring and interacting with these species and their ecosystems in the last decade alone, than the majority would in multiple lifetimes. I’ve conducted, monitored, observed and even investigated the harmful results of countless fish salvages. I could count on my hands the number of salvages and relocations that addressed all of the issues raised in these pro and con posts, the referenced article or countless other studies and operational guidelines rev salvage/handlin/relocation.
In the simplest of terms, unless you know what’s going on in the system wrt those issues, either the fish are fine because temp and DO are being maintained by ground/hypothetical flow (and thus the fish should be left), or DO and temps are significant issues, in which case the elevated stress hormones from handling under such conditions, the DO and temp issues w/ bucketing relocation, disease, parasite and fungus issues with handling at elevated temp and the shock of temp change at the (presumably) “better” (ie colder, higher DO saturation) receiving location. Again, the post focussed on the general public bucket brigade intending to help and pointed out, validly, the intended result is at best unknown and often detrimental.
I’ll add that some jurisdictions in BC are starting to clamp down on all fish salvages/relocations, not just bucket brigades (East Koots and Westslope Cutt populations as an example - as a result of a committee of very well respected and experienced gum boot biologists.)
Looking forward to my laughing emojis, think I’ve earned them!
Cheers!
Ukee
Anyway, as I approach my 35th year as a professional fisheries biologist, the past 25+ solely on the conservation and protection of freshwater salmonid habitat and populations, I am no armchair bio and would wager I’ve spent more days on stream specifically studying, monitoring and interacting with these species and their ecosystems in the last decade alone, than the majority would in multiple lifetimes. I’ve conducted, monitored, observed and even investigated the harmful results of countless fish salvages. I could count on my hands the number of salvages and relocations that addressed all of the issues raised in these pro and con posts, the referenced article or countless other studies and operational guidelines rev salvage/handlin/relocation.
In the simplest of terms, unless you know what’s going on in the system wrt those issues, either the fish are fine because temp and DO are being maintained by ground/hypothetical flow (and thus the fish should be left), or DO and temps are significant issues, in which case the elevated stress hormones from handling under such conditions, the DO and temp issues w/ bucketing relocation, disease, parasite and fungus issues with handling at elevated temp and the shock of temp change at the (presumably) “better” (ie colder, higher DO saturation) receiving location. Again, the post focussed on the general public bucket brigade intending to help and pointed out, validly, the intended result is at best unknown and often detrimental.
I’ll add that some jurisdictions in BC are starting to clamp down on all fish salvages/relocations, not just bucket brigades (East Koots and Westslope Cutt populations as an example - as a result of a committee of very well respected and experienced gum boot biologists.)
Looking forward to my laughing emojis, think I’ve earned them!
Cheers!
Ukee
Reel Time
Well-Known Member
I may be the armchair biologist, although I grew up with my mom who worked for the DFO late70's to mid 80's. Lots of knowledge passed on. As well, myself witnessing plenty of stranded pondings of coho while working forestry. People should question why are these fish swimming up stream to stranded streams, why do they live? why are they healthy? I remember the first time seeing this while working. Forest engineers and RP Bio's assured this is very normal for coho. Most may bury under rocks all day, never exposing themselves to predators. I question the human involvement for Coho salmon. They are freaking resilient.
IronNoggin
Well-Known Member
UkeeDreamin
Well-Known Member
UkeeDreamin
Well-Known Member
Very common for Westslope cutts (which I find share quite a few life history strategies with coho at the rearing stage). Thompson mainstem Chinook and steelhead also utilize intrastitial spaces in the substrate for overwintering, burrowing exceptionally deep. Going subsurface during summer drought, when juvies should be consuming as many calories as possible, is less than ideal but it is well documented in the scientific literature and Ive witnessed it many times in BC on the coast, in the Interior, north and south.
Cheers!
Ukee
Thanks again for your participation on this forum, Ukee - and specifically on this thread. It was readily obvious to me from your post that you had considerable experience and pertinent insights to offer (and you too, Dave). It's too bad that some posters with less experience aren't open to expanding their sometimes limited understanding of some issues and instead wish to label people with inaccurate and demeaning labels and keep the dialogue instead acrimonious and juvenile rather than complementary. Thanks for taking the high road! 
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