Electroshock surveys

Acristickid

Acristickid

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What is the typical mortality rate?

Is it very detrimental?

What are other alternatives?
 
What is the typical mortality rate?

Is it very detrimental?

What are other alternatives?

I think it’s advertised as very low mortality, and very safe. Not sure I’ve actually seen that validated anywhere, but, FWIW. Probably the conditions it’s done in matters more than the actual electrofishing.

Alternatives? I’ve heard spincasting for Trout is almost as good as electrofishing?
 
The surveys I’ve participated in were eye-opening. Didn’t see much impact on the larger trout but many smaller trout and secondary species were lost. Just my observations, no scientific basis. Not sure of the relationship of “voltage” used versus effectiveness and/or mortality.
 
Thanks for the info.

I got the gist of the articles- it depends. Hah, same answer from UT fish and WA fish.

Question- I apologize if this was somewhere in the literature, after 10 or 15 minutes of reading that science stuff , my eyes start to glaze over my ADD has me looking out the window.

Does the limestone water increase the conductivity ?
 
Thanks for the info.

I got the gist of the articles- it depends. Hah, same answer from UT fish and WA fish.

Question- I apologize if this was somewhere in the literature, after 10 or 15 minutes of reading that science stuff , my eyes start to glaze over my ADD has me looking out the window.

Does the limestone water increase the conductivity ?
Yes, with no influence from anything other than natural geology, limestone waters have much higher conductivity than freestone waters, allowing crews, when having both types of equipment, to most effectively use DC electricity rather than the more potentially damaging AC. AC has in the past been preferable in low conductivity water because of its larger electrical field and greater effectiveness in that situation.
 
I remember many years ago they shocked the Letort in the C and R section. There were plenty of fish so it was a success for that part. However I was talking to Charlie a few evenings later and he said all the trout that he watched for a long period of time was no where to be found. Many of them had constant holding areas that he observed for many days. About 20 plus years ago years the water cress disappeared in many sections and so did the fish. Currently the stream bottom is all mud with almost no cress in town.
The last time I saw them shock Big Springs they came up with large numbers of trout. Many were of trophy size and or over 15 - 16 inches. A few weeks later I could not find many of those fish. I understand they can and do migrate but I observed and fished about mile of water several times. Also I noticed that the cress bugs all but disappeared.
 
I remember many years ago they shocked the Letort in the C and R section. There were plenty of fish so it was a success for that part. However I was talking to Charlie a few evenings later and he said all the trout that he watched for a long period of time was no where to be found. Many of them had constant holding areas that he observed for many days. About 20 plus years ago years the water cress disappeared in many sections and so did the fish. Currently the stream bottom is all mud with almost no cress in town.
The last time I saw them shock Big Springs they came up with large numbers of trout. Many were of trophy size and or over 15 - 16 inches. A few weeks later I could not find many of those fish. I understand they can and do migrate but I observed and fished about mile of water several times. Also I noticed that the cress bugs all but disappeared.

I'm not a biologist, but have tagged along on quite a few electroshock surveys over the years, including multiple times on a stream that I live close to and fish routinely. I've not found dead trout after the surveys nor have I seen or believed that fishing was harder a week later than before the survey. Anecdotal information for sure, but I can't believe that they could routinely do surveys on the same stream and not have the quality of the fishing tank if it was really detrimental.
 
Many of us who talked to Charlie know that he wasn't a big fan of electrofishing surveys.

I've tagged along on many of these, especially Big Spring in recent years, and I have never had reason to suspect any significant mortality.
 
I participated in electrofishing and telemetry tagging of fish. No fatalities from the electroshocking and handling to insert the tags. The fish revived and returned to the log jams where they were first caught. Technician tracked them the rest of the season and eventually had a couple get taken by herons.
 
I echo posts 8, 9, and 10. When I tagged along, there were nearly no mortalities. Then, fishing some of these spots a couple of weeks later, I caught and released the numbers and sizes of trout that I typically did. I would think the mortality rate is quite low.
 
Assuming you guys are talking about Charlie Fox here?

Having read both of George Harvey’s books, he also thought that electrofishing hurt the fish
 
Is it possible that most folks with a strong opposition to electroshocking are anglers using low catch rates to assume fish populations that are later humiliated when electroshocking reveals the opposite? ;)
 
Assuming you guys are talking about Charlie Fox here?

Having read both of George Harvey’s books, he also thought that electrofishing hurt the fish
Technology for electrofishing has come along way since Harvey's time.
 
I recall reading what Mr. Harvey wrote, as noted in DFG's Post #12. But, I never saw disastrous results after places were shocked. And, what Lyco stated in Post #14 would seem to be true, too.
 
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