How many trout die "doing" pictures

[Don Andersen]

Research has shown <> 50% of trout die after 30 seconds and 100% of trout die if kept out of the water for 60 seconds.
Fishermen don't kill fish, cameras do.

Don

[Flieguy]

that's very different than statistics I have heard for trout C&R mortality.

I got this from a Trout Unlimited head biologist:

single, unbaited hook-7% mortality

treble hook, unbaited-10% mortality

baited hook-25% mortality

Trout also recover more quickly than walleye, which release a hormone that causes great stress and does not leave their system for quite a while. If a trout will die, it is usually within a couple hours of being caught, whereas walleye may die 24 hours later.

this is as best as I can remember from the conversation with the Bio.

other factors affect it such as how the fish was handled, water and air temp, size of hook and where it was hooked, etc.

I think that due to the great number of variables, it would be difficult to accurately measure mortality rates, results vary quite a lot from study to study

[Taco]

What did Brian say about factoring in grin and grips and summertime water temps?

[BobLoblaw]

Well, Don, that's good enough for me.
From now on, when I post a trip report, I will simply describe the fish i caught or draw a sketch from memory.

[CanuckShooter]

The fish I catch suffer a 99% mortality rate because we eat them, the only fish released are big lake trout. People shouldn't be allowed to catch and release any thing beyond their daily limit in my opinion.

[Redfrog]

This raises a few questions.

So catch and release doen't work very well after all?

How many fishermen have caught the same fish more than once?

Do catfish have 9 lives or do they die in 30 seconds as well?

Ever bring a bunch of perch home from ice fishing and have them spring back to life in the sink?

Wonder what the bucket brigade uses to keep their fish alive while transporting in the bucket?

[tight line]

I don't believe those stats at all. I agree taking pics if done unorganized can be hard on fish, but those stats are pretty drastic. Where is the source Don? I have been in hatcheries and seen Brood bows being milked, and alot of the time out of the water for close to a minute, and these fish get handled repeatedly, and have been surviving for years. I have caught the same fish repeatedly(Cutt) that i have photo'd and been out of the water for at least 30 secs. Must be a lucky fish defying the odds... Lol.

[jts1]

Questioning the validity of them stats also. Handling and time out of the water are critical when releasing fish. And the fragility will differ from one species to another. But this 60 seconds and 100% morality rate for Trout seems a little off.

[Speckle55]

Just do this then release.. but I still get some mortality

David

[pikergolf]

I don't believe blanket stats like that for a second. In the heat of summer I think the time frame is generous and in prime trout I think they can stand it. I think the time it takes to get a fish landed is the biggest variable. Light lines and long fights are not a fishes friend, trout or otherwise. We owe it to fish we are going to release to use the heaviest line that we can get away with.

I am not a fan of taking a picture of every fish a guy lands, but if a person is ready and knows what they are doing it's a very short process. A rule I read about when I was a kid, back with the dinosaurs, went like this. When you remove the fish from water catch your breath, hold it till the fish is back in the water. I did this for many years, it helps build empathy for the fish and surprises you at how quickly the time passes. A minute is a long time when you can't breath, for both man and beast.

[Don Andersen]

Physiological Effects of Brief Air Exposure in Exhaustively Exercised Rainbow Trout (Oncorhynchus mykiss): Implications for "Catch and Release" Fisheries

R. A. Ferguson, B. L. Tufts

Published on the web 11 April 2011.

Abstract

Rainbow trout (Oncorhynchus mykiss) which were air exposed for 60 s after exhaustive exercise initially had a much larger extracellular acidosis than trout which were only exercised. In both groups, however, plasma pH returned to normal by 4 h. Blood lactate concentrations were also greater in the air-exposed fish and continued to increase throughout the experiment. During air exposure, there was retention of carbon dioxide in the blood, and oxygen tension (Po2) and hemoglobinxygen carriage (Hb:O2) both fell by over 80%. After 30 min of recovery, however, blood gases resembled those in fish which were only exercised. Finally, survival after 12 h was 10% in control fish and 88% in the exercised fish but fell to 62 and 28% in fish which were air exposed for 30 and 60 s, respectively, after exercise. These results indicate that the brief period of air exposure which occurs in many "catch and release" fisheries is a significant additional stress which may ultimately influence whether a released fish survives.


I should never rely totally on memory. Only 70% die after one minute & 38% after 30 seconds.

And for those long winter nights, there is a pile of good reading here.
http://www.nrcresearchpress.com/journal/cjfas


And as far as egg stripping, those fish are slowed with an anesthetic reducing handling stress.

[J D]

Call BS on that study but I do agree time out of water should be limited.

I work with trout for a living and if these stats were correct I would be bankrupt.

[commieboy]

Originally Posted by Don Andersen

Fishermen don't kill fish, cameras do.

Don

Who holds the camera while it kills the fish? Or are the cameras running around and killing fish at random? Are we talking about self aware technology?! Holy crap! Rise of the machines!!!!!!

But seriously, I believe this. Still, I think if you are a responsible, experienced fisherperson, a picture doesn't much harm.

Keep the fish in the net until you're ready to take the shot.

Have the camera person pre focus on a part of your body which will more or less have the same distance from the lens to the fish so there is minimal refocussing.

If the first pic doesn't work out, get the fish back in the net for recovery time before trying again or give up and snap a pic in the net.

I have learned through much experience that studies are skewed to show the results that they want to show.

[rycoma]

You mean everything in main stream media and on the internet isn't always true? Oh god I'm gonna go and hide!

[Norman]

Those numbers seem quite high to me, so high in fact that I believe every species of trout would be on the protected list if it were true. I have no doubt that trout or any fish for that matter should not be out of the water for long and some do perish due to mishandling. It's good to bring up now and again to get people thinking about how they handle fish, so it's never a bad topic to discuss. I always use a net and try to do my part to keep the fish in the water but if I have someone with me I will at times get a quick photo if the person I'm with is ready with the camera.

[catnthehat]

Originally Posted by Speckle55

Just do this then release.. but I still get some mortality

David

This is how most of mine get taken
I normally just unhook them at the boat these days unless I am keeping them
Cat

[RavYak]

Originally Posted by Don Andersen

I should never rely totally on memory. Only 70% die after one minute & 38% after 30 seconds.

You missed the most important part of that journal... The fish were fully exhausted by chasing them for 10 minutes until they refused to swim away... 12% of the fish that were never removed from the water died from this test just due to the exhaustion... This experiment was also done with fish that had recently undergone major surgery and that were handled multiple times during their recovery period... In short this is a worst case scenario and far from the average catch and release rates.

For example the 12% mortality of fish with no air time is three times that of the following test which actually included manual hooking and then playing a fish to a point where it could be handled. With triple the mortality rate it is clear how important it is to not overplay fish.

http://digitalcommons.unl.edu/cgi/vi...xt=ncfwrustaff

What I would like to see is a test done the way this experiment did it(actually hooking the fish then playing enough to handle) but with 30 and 60 second times out of water after catching. I don't doubt that there would be increased mortality but I highly doubt it would be close to your posted experiment. If it is the same 1/3 as the base result then that would mean around 87% of fish would survive at 30 seconds and 76% of fish out for 60 seconds which are numbers that to me could be realistic.

Last but not least, if you can't figure out a way to get a picture of a fish without having to have it out of the water for even 30 seconds then you are doing something wrong...

Good to know you have never taken a picture of any fish you have caught though...

[RavYak]

Originally Posted by commieboy

I have learned through much experience that studies are skewed to show the results that they want to show.

That isn't really the case with this one, it is a decent experiment and they clearly state the following.

"The purpose of the present experiments was not to predict actual percentages of mortality in the wild when exhausted fish are briefly exposed to air."

It was an experiment for them to view the affect of exhaustion and air deprivation on the fish's physiological state(blood lactate etc). The catch and release implications were included as a side note because similarities can be drawn.

Don is the one that skewed the study(by misreporting it) to show the results he wanted(and yet he was still off by a factor of over 30% to his original claim)...

[Don Andersen]

As Norman says : minimize exposure to the air. Take a quick shot.

Watched a guy spend 20 minutes landing a 5 lb. trout one day. Then netted it & while it flopped around on the bottom of his boat he looked for something. Then he finally found the something and played with some fish some more. Got out his camera and took shot after shot. Then carefully lowered the fish into the water and say's to one and all. "It's dead".

What a surprise.

I frankly don't much care whether or not you believe what a published scientist has proved true. The reality is - time out of water kills fish with "grip and grin" camera shot being a major contributor.

If you want fish to fish for, take care of them.

And yes, I do take pictures of fish.

[grinr]

Originally Posted by Speckle55

Just do this then release.. but I still get some mortality.
David

How do you know that you get some/any/none mortality??
I know for certain that I see 100% mortality with fish that I release into my cooler.The rest generally swim away never to be seen again.

[Don Andersen]

Originally Posted by RavYak

That isn't really the case with this one, it is a decent experiment and they clearly state the following.

"The purpose of the present experiments was not to predict actual percentages of mortality in the wild when exhausted fish are briefly exposed to air."

It was an experiment for them to view the affect of exhaustion and air deprivation on the fish's physiological state(blood lactate etc). The catch and release implications were included as a side note because similarities can be drawn.

Don is the one that skewed the study(by misreporting it) to show the results he wanted(and yet he was still off by a factor of over 30% to his original claim)...

Rav...

As I pointed out and apologized for is relying on memory. It had been several years since I read the study.
I was wrong and corrected the error.
OK!


Don

[commieboy]

Originally Posted by RavYak

That isn't really the case with this one, it is a decent experiment and they clearly state the following.

No that I dispute the findings, but many experiments are set up this way and worded specifically to make them seem impartial or unbiased. Semantics plays a large part in published studies.

I can almost guarantee that another study exist which will at least partially contradict the findings of this study.

Don't put too much stock in the words of scientists. Funding will almost always skew results, even in the case of seemingly impartial studies.

Still, don't bug the fishes more than you already have!!! Get them into the water quickly.

[RavYak]

Originally Posted by Don Andersen

And yes, I do take pictures of fish.

Nice brown, I need to catch one of those. I can't believe you let your camera kill it though...

Your thread is a good reminder but you should have used a little more tact

[chimpac]

Fish mortality percentage caused by catch and release can be debated but the fact is there is mortality.

Is the entertainment provided to people who do catch and release worth any mortality.

[BeeGuy]

Originally Posted by Don Andersen

Research has shown <> 50% of trout die after 30 seconds and 100% of trout die if kept out of the water for 60 seconds.
Fishermen don't kill fish, cameras do.

Don

Ummmmm

Which research is that?

[Don Andersen]

Originally Posted by BeeGuy

Ummmmm

Which research is that?

Read the thread.

Abstract is there.

Don

[Don Andersen]

Originally Posted by RavYak

Nice brown, I need to catch one of those. I can't believe you let your camera kill it though...

Your thread is a good reminder but you should have used a little more tact

Rav...

Gave on tact.
Don't work.

Don

[CanuckShooter]

Originally Posted by Don Andersen

Physiological Effects of Brief Air Exposure in Exhaustively Exercised Rainbow Trout (Oncorhynchus mykiss): Implications for "Catch and Release" Fisheries

R. A. Ferguson, B. L. Tufts

Published on the web 11 April 2011.

Abstract

Rainbow trout (Oncorhynchus mykiss) which were air exposed for 60 s after exhaustive exercise initially had a much larger extracellular acidosis than trout which were only exercised. In both groups, however, plasma pH returned to normal by 4 h. Blood lactate concentrations were also greater in the air-exposed fish and continued to increase throughout the experiment. During air exposure, there was retention of carbon dioxide in the blood, and oxygen tension (Po2) and hemoglobinxygen carriage (Hb:O2) both fell by over 80%. After 30 min of recovery, however, blood gases resembled those in fish which were only exercised. Finally, survival after 12 h was 10% in control fish and 88% in the exercised fish but fell to 62 and 28% in fish which were air exposed for 30 and 60 s, respectively, after exercise. These results indicate that the brief period of air exposure which occurs in many "catch and release" fisheries is a significant additional stress which may ultimately influence whether a released fish survives.


I should never rely totally on memory. Only 70% die after one minute & 38% after 30 seconds.

And for those long winter nights, there is a pile of good reading here.
http://www.nrcresearchpress.com/journal/cjfas


And as far as egg stripping, those fish are slowed with an anesthetic reducing handling stress.

Further evidence that catch and release fishing should be banned. Let the science tell you what your doing by hooking, playing and releasing several dozen fish a day....

[Bushrat]

Originally Posted by CanuckShooter

Further evidence that catch and release fishing should be banned. Let the science tell you what your doing by hooking, playing and releasing several dozen fish a day....

Fish are tough, sure some die but the majority are not dragged out of the water for pics and handling, most simply released without leaving the water no pics taken, usually no worse for wear. Our fish populations have come back since the old meat fishing days so there is merit in catch and release. They have a far better chance of survival after release than they do in a creel.

[grinr]

These were fish as stated that were chased(played) to exhaustion,in a controlled environment,to the point that they were captured by hand prior to being deprived of water for 30-60s....apples to oranges compared to real world angling conditions.
Fish that are played quickly,landed swiftly,handled properly with minimum amount of removal from water do just fine.....being C&Rd is nothing more then a slight inconvenience and disruption to their daily routine.This is a big part of why I advocate the use of fish friendly landing nets vs. no net. Generally speaking,I can land and handle fish much more quickly and efficiently with a net vs. no net where one often has to excessively tire the fish out to handle it.
As mentioned,the science is often skewed(in any field of study) to show the desired results.For every "CnR is bad" study such as this,I can show you 3 more that show mortality rates between 1-5%, or others with 99-100% survival rates when fish are handled properly by experienced anglers.