A tale of two streams...

afishinado

afishinado

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The twin valleys are split by Crystal Clear Mountain. In the valley to the west, Catch’em Creek flows cold and clear. To the east is a twin stream called Releas’em Run.

Catch’em has open harvest regulations, while Releas’em is catch & release only.

According to a shocking survey done at the end of March, both streams have an estimated population of 2000 catchable sized wild trout going into the early April trout season, with 600 trout of legal, harvestable size including 200 fish 12” or greater.

The flows and weather were great in April, and anglers flocked to both streams to try their luck. Because of these good conditions, angler usage was very high on both streams.

At the end of April on Catch’em Creek, 300 legal sized fish were harvested by anglers (that’s an average of 10/day) of which 100 trout 12” or greater were removed.

Releas’em Run had close to the same population of trout at the end of April as in the beginning of the month.

At the end of May, on Catch’em, a total of 400 legal sized fish were harvested with 150 of that total being 12” or greater (that’s an average of just over 3 fish per day being harvested in May). Leaving 200 legal sized fish including 50 fish being 12” or greater left in the stream.

On Releas’em Run, less than 100 fish have perished, leaving well over 500 decent fish including close to 200 over 12” still roaming the riffs and runs.

The summer was rainy with moderate temperatures. Catch’em Creek saw little angler usage over the summer in to the early fall.

To the east, Releas’em Run had a steady amount of angler usage, mostly during early mornings and evenings right through the early fall. It fished well throughout the entire season.

The trout carried well on both streams with the favorable conditions going into the spawn. As the season turned to fall, the rigors of spawning took its toll on the fish, along with predators and lastly a long, hard winter with anchor ice forming in the shallows.

Winter slowly gave way to spring, and the stream levels were favorable at the end of March for a shocking survey, which was done on both streams during the same week as the year before.

The survey results were in, and terms like mortality rate, recruitment rate, harvestable surplus, compensatory mortality, additive mortality were all considered and calculated by the fisheries biologists. Finally, all data was plugged into a formula which might go something like N1 = N0 + B - D + I - E.

The findings…the twin streams, a year later both have the same biomass of wild trout with an estimated 2000 catchable sized fish including 600 legal sized trout with 200 fish 12” or greater.

According to the fisheries biologists, harvest has little or no effect on the wild trout populations.

I guess they’re right………right?

 
...as Danny patiently waits for the un-divuldged information about to be offered...
 
No more info, Dan. A tale. Like Rumpelstiltskin, Cinderella or Jack and the Beanstalk........
 
I seem to remember a study in Idaho that had a similar conclusion. Wild and stockers can co-exist.
 
This dream is to mike as the sweedish bikini team dream is to me.

Only difference in streams is catchem crik has poor fall and winter fishing from a size stand point.
I wonder what the size distribution of the fish over 12" is between the two criks the next spring?
 
All of the old timers say that Release Em Run doesn't fish like it used to back in the day.
 
Were they stocked? Did the streams rely on wild trout only? Were the water temps comparable? Do trout migrate to colder water on either creek? Is poaching a problem?

I am a believer in c/r regulations. I believe that some streams I know of are much better now than they were when I started fishing because almost all guys who fish them release the fish they catch, even without official c/r regulations.

One suffered from overharvest during the year of the locust (what most people like to call by the e------- name cicada), and only this year has it fished as it did before the slaughter during the locust year ( 3 or 4 years ago). This year there is a nice population of various ages of trout. For a couple years, all you could catch were mostly the little guys the locust guys didn't kill.

Anyhow, there are lots of questions about the two cricks you wrote about.
 
jebus, afish, and you say my poasts are confusing.
 
teedee wrote:
I seem to remember a study in Idaho that had a similar conclusion. Wild and stockers can co-exist.

Got a link?
 
It was the best of times, it was the worst of times.
 
I dunno. I might fish UNT to Catch'em, so narrow it would not be stocked by the pfbc. Or fished very often. Heck, I fished two streams like that yesterday in NEPA, one class A on public land. Would have been shocked to see another fisherman, even more so one keeping small brook trout.

So I am hardly a trophy trout hunter. But I somehow doubt that biologists are reporting annual spring biomass comparisons without reporting a huge harvest effect on summer/fall size structure. pfbc reports often give both biomass and size. first one I pulled below:

"Site #1 - Downstream of SR 0534 (Site length 352 yards)
Total number caught on first pass = 144 Number of brown trout 7 to 12 inches = 34 Number of brown trout 13 inches = 2 Estimated wild brown trout biomass was 46.4 lbs per acre"



 
Alright......feeble fable, maybe.

Some random thoughts:

I constantly read that creel limits and harvest have no or little effect on wild fish (trout) populations. I believe this is true in the long term, like a season or seasons.

But in these two streams, from an anglers perspective, fishing both streams on June 1st many of the fish (and mostly larger ones) are cropped out of Catch'em in the 8 previous weeks of harvest while many/most still remain in Releas'em. Pick a number: 5 stringers, 55 stringers, 155 stringers of fish were taken out. Which stream would fish better on June 1st? Or in the early fall?

True, that in the course of a year, the natural mortality rate will tend equal out the total biomass, while the age structure of the fish is up for debate on both streams (as Mo pointed out).

Is a fish "wasted" if it dies of natural causes like disease, a predator, flood, drought rather than being harvested and eaten?

(From another active thread on here) Does cropping out wild fish help or hurt a stream and/or increase the average size of the fish? I am not near smart enough to know if harvesting fish from any stream is hurting or helping the wild fish population.....so I turn them all back.

In PA, we are lucky to have many hundreds of quality wild trout streams to fish. Make as little impact as possible. Return the fish... share with others.

Wild trout streams are self-sustaining if we take care of the stream and release the fish we catch.

 
I personally don't fish for stockies, fish w/o barbs, and have never kept a trout. But I see an irony here... people sometimes want science based trout management... until they don't like what the science says :)

there are so many miles of low pressure unstocked trout water in PA that I think the state deserves credit for current mgt practices.

 
k-bob wrote:
I personally don't fish for stockies, fish w/o barbs, and have never kept a trout. But I see an irony here... people sometimes want science based trout management... until they don't like what the science says :)

there are so many miles of low pressure unstocked trout water in PA that I think the state deserves credit for current mgt practices.

True above. Many give back, or at least put back, and do not take...like you. Is it a bad thing to try to get the word out and teach others to do the same?

I talk to dozens of anglers on the stream every season that have no clue that the trout they catch, or sometimes have on their stringer are wild, streamborn trout. Don't underestimate the amount of anglers that believe all trout they catch come in big white trucks.



 
Regarding your scenario.

Is the PFBC actually asserting what you say they are asserting in regard to that sort of situation?

I don't think they are.

The PFBC often proudly talks about their success on streams like Saucon Creek, Spring Creek, Penns Creek, Little Juniata, Fishing Creek, Slate Run, Cedar Run, etc.

These streams were previously stocked and had state-wide harvest regs. The PFBC made changes to reduce harvest, and the populations responded.

They are proud of these successes, as they should be.

In the case of brook trout, I don't think many PFBC people would deny that stocking over brook trout hurts brookie populations. The evidence from electrofishing is completely overwhelming on this. The cropping is severe and the data shows it indisputably.

They have taken many brookie streams off the stocking list for this reason. And tried to take a lot more off, but got beaten back by local sportsmens groups that went to their local legislators, and those legislators said essentially: stock our streams or else we'll get rid of you, and maybe your agency as well.


 
TB: "In the case of brook trout, I don't think many PFBC people would deny that stocking over brook trout hurts brookie populations. The evidence from electrofishing is completely overwhelming on this. The cropping is severe and the data shows it indisputably."

actually the research says that stocking typically does not hurt wild trout populations, see below page 8:

"Rarely has any study shown negative impacts to wild trout at the population level due to catchable stocking."

https://collaboration.idfg.idaho.gov/FisheriesTechnicalReports/res10-13Meyer2010%20Wild%20Trout.pdf

moreover, where stocking effects on wild trout populations are seen, they probably result from increased fishing pressure attracted after stocking, not from clueless, short lived stockies themselves (see above article). page 8 "we believe that increased angler effort is the most common cause of decline in wild trout abundance associated with hatchery stocking, when such a decline occurs."

btw, would stockies cause cropping?: if anything wouldn't the stockies take out the smaller wild fish, not the bigger ones?

So if anything affects PA brookie populations after stocking, it is probably the added fishermen more than the added fish. PA has a great amount of unstocked wild brookie water - literally hundreds of streams - so I can live with the impact of stockie fishermen on some of them.





 
I agree that the main effect from stocking is increased harvest, rather than from competition. I've said that all along.

But that effect is what actually occurs, and what suppresses the trout population.

On many streams hatchery trout are stocked over wild trout and the limit is 5 fish per day. The stocking attracts large numbers of harvest oriented anglers, who harvest the wild trout as well as the stockies.

Which greatly suppresses the trout population. The PFBC knows this.

Which is why on many streams they have changed that situation, from about 1980 up til today. And often talk about their successes in this regard.

In many cases they have achieved excellent increases in trout populations by doing so.


 
the literature doesn't suggest that the main effect from stocking is through harvest, it suggests the only effect of stocking is through harvest. article linked above.

my casual guess-estimate is that at least for NE PA, of all of about 10% of wild brook trout streams are stocked. that includes every little jump-across stream of course. glass much more than half full :)
 
k-bob wrote:
the literature doesn't suggest that the main effect from stocking is through harvest, it suggests the only effect of stocking is through harvest. article linked above.

Whether the harm is done via harvest or competition or some combination of the two, what is most relevant is that the harm is done.

In PA, where trout are stocked over wild trout, the regs on the vast majority of these are the general regs, i.e. 5 fish per day, 7 inch minimum. So, yes, the great majority of the harm is coming from harvest, not competition. The stockies are quickly removed.

In the far fewer cases where hatchery trout are stocked over wild trout, and special regs prevent the harvest of the stockies, does competition have an effect?

You'll have to talk to Mike about that. He says yes, in regard to Donegal Creek, at least.
 
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