DNR shock sampling thread

wwfoste · Sep 4, 2024

I'm starting to help DNR with sampling of our wild rivers when I get a chance. Was going to use this thread to share some of it.

Went today to a river I like to fish when water temps allow. It's a fairly infertile stream but has wild browns and rainbows. I was prepared to be humbled and wasn't disappointed. We found 108 trout in 200 yards, about 5 browns in the 12" range. They said the last time they sampled here 6 years ago they pulled a 20" one out.

It involves a line of shocker packs with netters and buckets following. Along the way the bucket contents are dropped into live well mesh boxes and then we collect the fish on the way back. 3 runs are done in the same section so they can develop a work down curve. Then the fish are all separated into species and the non trout ones are weighed and released while the trout are measured and weighed individually. A total of 4 non-trout species were present, which is pretty sparse. We had jump rock suckers, long nose daces, horny head chubs, and redhorses.

Then they kept a selection of them to send off for whirling disease testing, as a just in case, not due to any evidence.

They even let me run one of the shocker packs on the last run. I'll post more as I do some of the others.

WorknPlay · Sep 4, 2024

It is great, you are working with the DNR to do some conservation work. I want to say that in the one picture of all of the workers in the stream, it reminded me of the movie (Ghostbusters). Where they are all wearing their proton packs on their backs to fight the ghosts.

Ard · Sep 5, 2024

This is going to be a great thread and I'm going to make it a sticky so it stays on top of General Discussions. Be sure to update as often as you can.

ARTSCH · Jan 19, 2026

Why do you remove the suckers from the river? What impact do they have on the trout?

Angler J · Sep 10, 2024

This was an incredibly interesting post! Did you just reach out to the DNR to participate- or was there some kind of selection process? About how long did the session take?

wwfoste · Sep 10, 2024

I took part in one last year. They'd asked TU for volunteers for sampling the big river here. I'd been talking with our fisheries biologist anyways about our brook trout streams and other wild streams. I send him information on where I went and what I found for each one. I told him I would like to help out for any samplings they do, so he sent me a list where they would need help. They're doing some other tiny streams they didn't need help with. I'm planning on doing at least 3 more and there are a few more I won't be able to help out on.

This one took about 5 hours because we didn't have enough people to do the gathering and the counting at the same time. So we had to do all 3 runs, then do the counting/weighing.

wwfoste · Sep 10, 2024

It's also always fun to know I could and have fished through this section and may get a couple strikes. And there were potentially over 100 trout there.

TwoThumbsUp · Sep 10, 2024

I did a couple when I lived in East TN and all I could think about was "what am I doing wrong". I couldn't believe the numbers and size of fish that were in some of the streams.

wwfoste · Sep 25, 2024

Had the second shocking day today on our main river that I helped with last year, but this time much closer to public access. Felt like we had less trout than last year but waiting for the fisheries biologist to send me the totals and the list of all the species found. We did find several good sized browns. My second one for this week is going to get rained out.

clouserguyky · Oct 5, 2024

Very cool! Good work. I studied wildlife management and fisheries biology in college and I got to do some shocking here in KY. I remember as a junior, I was netting fish behind my buddy Jimmy who was running the shocker on a small river. Lots of diversity, and also lots of average size smallmouth.

Then at one point, a 20” smallie came floating up, and in a moment of stupidity, my angling instinct took over and instead of just netting the fish, I reached in with my left hand to lip the fish as fast as I could, and in so doing I got to see what those shockers really do!

plecain · Oct 5, 2024

I participated in a census on a small non-stocked brook in NH. It was the first time I'd done that.

I was completely amazed at the number of brook trout in that small stream. It was at least 10 times what I expected.

View attachment DSCN1428.JPG

I had fished that brook earlier in the season. One of the inhabitants.

View attachment DSCN1430.JPG

wwfoste · Oct 5, 2024

plecain said:
I participated in a census on a small non-stocked brook in NH. It was the first time I'd done that.

I was completely amazed at the number of brook trout in that small stream. It was at least 10 times what I expected.

View attachment 163919

I had fished that brook earlier in the season. One of the inhabitants.

View attachment 163921

Humbling isn't it?

dudemanspecial · Oct 5, 2024

What state?

wwfoste · Oct 5, 2024

I'm in SC. Looks like plecain was in NH.

wwfoste · Nov 5, 2024

@Ard You can unpin this one. Helene impacts cancelled all other shockings. I'll pick it back up next year.

Ard · Nov 5, 2024

I'll leave it here for a while.

L-2 · Nov 5, 2024

So, after handling all these trout out of the water and capturing data for the benefit of the fish… 👍

What’s your opinion on holding a fish ( a reasonable time) for a picture?

Lastly this can be a hot topic if you don’t want to answer.

I’ll delete my post.
Thanks!

wwfoste · Nov 6, 2024

L-2 said:
So, after handling all these trout out of the water and capturing data for the benefit of the fish… 👍

What’s your opinion on holding a fish ( a reasonable time) for a picture?

I think in general it's fine, but as with anything it depends. What's the water temp? What's the air temp? How long did the fight last? Are your hands wet? How many times are you taking the fish out of the water for a pic?

With the sampling, there is some mortality from the shocking or handling. Those get sent for whirling disease check.

The process for the fish in this is they get shocked, caught with a net and put into a bucket filled with water. Every so often they get put into a live well (a mesh box in the water). Then we collect them together and then separate them by species into different live wells. The non trout are quickly weighed by species and released. The trout are pulled out of a live well or bucket, quickly measured, weighed and put back in a live well until released. Probably less time than your typical pic on a drift boat.

L-2 · Nov 6, 2024

All good points…
I guess an important data point would be how many times does a fish get caught in a week?
You could also argue the fish you surveyed have been caught all week. 🤷🏻‍♂️

Otherwise best bet taking pictures or not is we should think about resting a stream. It could be off one week and on another?

So fish have time to recuperate on heavily targeted waters.

Anywho, not trying to argue against surveys thanks for helping out.

Just think there is no harm to a responsible fish picture.

wwfoste · Nov 6, 2024

As anyone can tell from my posts, I take plenty of pictures of fish. I'm sure some would say I'm doing undue harm to them. I'm not opposed to fish pics. I try and mitigate impacts by avoiding fishing at marginal water temps. My pictures take less then 10 seconds from net to water.

As far as the fish from the surveys being caught before and after, possibly. Those would be better fishermen than me. Last year I went back to around the site of a survey (a few weeks later) where we found over 80 wild browns in less than 100 yards. I had 2 strikes.

wwfoste · Dec 20, 2024

I put together a video of the two sampling days to share with my dad. Here it is for any that have never been involved with one.

wwfoste · Jun 26, 2025

Went and helped DNR sample the last brook trout restoration stream. The main goal was to make sure they were reproducing. In this stream, an upstream pond had been purchased, drained, and demolished. Some fine sediment has made it into the stream, but they're still finding room to reproduce. Found over 20 young of year and 8 adults in the sampling section. Hopefully future tropical storms/hurricanes will help blow it out some.

Cacti · Jul 10, 2025

wwfoste said:

Are these Brooks? Never seem then with only orange spots.

Ard · Jun 26, 2025

his is extremely interesting WW. thanks for updating things.

Cacti · Jul 10, 2025

You guys look like Ghostbusters with those packs.

wwfoste · Jul 10, 2025

Cacti said:
Are these Brooks? Never seem then with only orange spots.

Yes

wwfoste · Sep 5, 2025

Went and helped DNR shock a brook trout stream today to make sure the population can support being used to provide the transplants for the brook trout restoration project we've started. For the upper site it was a 30 minute bushwack through rhododendron and downed trees before we started shocking. Found good populations though. Then worked our way back and worked a lower site.

Also took a few minutes after to fish a different section of the stream

Kinni David · Sep 5, 2025

I look forward to every update in this thread.

wwfoste · Sep 10, 2025

Went and helped on a feeder stream today. Only found about 30 trout, but tons of other fish. 3 passes, each pass counted separately.

Going to miss tomorrow where there are good chances of them getting ones over 20".

The jumble of everything collected

Separating out the various species for counting and weighing.

Sculpin

????

Striped Jumprock

Stoneroller

Rosyside Dace

Warpaint Shiner

Redbreast Sunfish

Yellowfin Shiner

Bluehead Chub

Mirror shiner

Longnose Dace

knotjoe · Sep 10, 2025

wwfoste said:
Hog sucker

These are some of the hardest fish to identify at hand size or smaller so don’t take this the wrong way. It’s only speculation on my part, but I don’t think either are Hogsuckers. First one is ambiguous and could be a number of species (White sucker, Notchlip RH, etc) at that size. Second one looks like a Striped Jumprock or something along those lines.

Loving the dorsal colors on the (Mottled?) Sculpins, it really pops! I’m used to the Banded Sculpins up here in Indiana which aren’t quite so colorful. We have both, but the Banded are far more common in my streams.

Great pics and write-ups, it’s hard to get those shots even with a photo tank.

thom · Sep 10, 2025

These are always interesting reports. In your experience what is considered to be an effective vertical barrier in order to isolate a population?

That Warpaint Shiner is looking good.

wwfoste · Sep 10, 2025

I wouldn't say I have the educated experience, but from what I've seen, it needs to be on the order of 15-20 ft.

timoteo · Sep 10, 2025

Interesting. Thanks for sharing.
Do those turtles eat fish? Are those newts? Isn’t the presence of newts an indicator of a healthy stream?

wwfoste · Sep 10, 2025

I'm sure that snapping turtle eats the fish. DNR would have removed it if we had the means then.

And the orange ones are newts. Not sure on what they indicate about the stream.

Ard · Sep 10, 2025

Nice ww!

wwfoste · Sep 10, 2025

Couldn't go today, but they shocked this one up today.

wwfoste · Sep 12, 2025

Went and helped shock a small brook trout stream that I've fished before. Found a bunch of young of year, so they're still hanging in there.

DNR shock sampling thread

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