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[jim]

I saw about 400 fry stranded in a small pool this morning. Is there anyone doing fry rescue here on the Vedder river?

[clarki]

Not having seen the small pool you are referring to, I wonder if the fry need rescue at this point in the year. Perhaps there is enough water in the pool, or enough oxygenated groundwater flowing through the gravel, to sustain them until the freshet begins?

[RalphH]

A couple of points.

As Clarki indicates water is flowing through the gravel and will fresh the pool.

However if the weather stays warm and dry the water in the pool may heat to a point it is lethal to the fry.

Often salmon spawn during high water and in lower water the gravel spawning bed is out of the water

Check the weather report. Rain is expected tomorrow and may be sufficient to raise the water level and flush the fry out.

I am not aware of any fry rescue squads. Not sure what the legalities are (intention is always everything) but in the past I have used a hat to scoop fry and move to the main current. You could go pro and get an aquarium net.

[jim]

thanx for the advice guys.
i will keep an eye on this mini pool, and the small fry living there.
yes, i can see the fresh water coming thru the gravel.

[clarki]

If considering a fry salvage operation on your own, this article has some best practices  https://www.pskf.ca/publications/salvage.html
 

[RalphH]

Good link!

I just wanted to mention that fry stranded in pools is common. I have also seen fry emerge from gravel that is out of the water - literally between my feet. They did flip flop to the water which was just a few inches away.

You can try to get them out if you can but it can be difficult, if not impossible, depending on the size of the pool and structure (rocks, wood debris) in the pool. I'd note that the link Clarki provided mentioned use of electroshock tools which certainly casual rescuers don't have access to.

[Dave]

Another thing to remember .. often the water in the pond the fry are in is considerably warmer than the main water body you are moving the fry to, which could result in mortalities from thermal shock.

[SuperBobby]

Except for the most extreme of circumstances, let mother nature do her job. Why does man always have to interfere?
It's like the old lady who brings a crow into the vet to fix a broken wing. Why?
It's like the woke tourist on an African safari that tells the conductor to stop the lion from eating the zebra.

The wild has been around longer than any of us, and it did just fine without us. And when I say help in only the most 'extreme' circumstances, I'm referring to a situation where man has severely caused an indifference of environment.

[RalphH]

Another thing to remember .. often the water in the pond the fry are in is considerably warmer than the main water body you are moving the fry to, which could result in mortalities from thermal shock.

When I had an aquarium for tropical fish this was something to watch for but easy to deal with. Typical case was buying fish at the pet store. They would be put in a plastic bag with water from the aquarium. At home I'd float the bag - water and fish, the aquarium for 15 or 20 minutes then open it up and let the water from the tank move into the bag. Just let the fish move out on their own. A bag or bucket could be used for them same purpose as a secondary holding receptacle for the fry. Put it in the river and let the water in the bag or bucket drop to the same level as the river. Then slowly release the fry. A temperature difference of a degree or 2 should make little difference to the fish.

[clarki]

Another thing to remember .. often the water in the pond the fry are in is considerably warmer than the main water body you are moving the fry to, which could result in mortalities from thermal shock.

I’ve participated in a couple of mid-summer fry salvage activities on the Little Campbell River. DFO SEP has a PDF that they circulated to organizations and a couple of the guidelines support your comment, Dave.

Fry salvages should occur when temperatures are below 16°C; at higher temperatures it is encouraged that you postpone salvage activities. If this is not possible, minimize handling to reduce stress.

Avoid temperature shock when moving fry; differences in temperature should not exceed 4°C (2°C per hour ).

[Dave]

Thanks Clarki. As Bob says, sometimes it's just best to leave things alone.

[RalphH]

River I was on Thursday was 8 to 9C  around 2pm. IME that river is usually warmer than the chilli V/C. Not much chance of it hitting 16C the past few days IMO.

[jim]

the river has come up and flow thru the gravel has increased. I was there this morning and i think the fry went downstream with the water flow.

[RalphH]

the river has come up and flow thru the gravel has increased. I was there this morning and i think the fry went downstream with the water flow.

that's good news! Thanks for keeping us up to date.