catch and release vs catch and keep regulation

[CRB]

Found this in Fly Fisherman; February 2004,
"The logic of limits", by Paul B. Downing, PHD


"
Table 1: Sustainable fishing pressure on hypothetical Stream X
Regulation................................................hours per day per mile
catch-and-keep......................................................5.2

catch-and-release
bait...................................................................15.8
bait, barbless......................................................62.5
flies, and lures....................................................110.1
flies and lures, barbless.......................................203.3

"

I saw this in the article today thought it would be good to bring up.
Thoughts?

 

[BrookieChaser]

There are 24 hours in a day.

 

[SteveG]

Every stream would be different due to water flow/volume, quality, and habitat, but it seems to be headed in the right direction.

 

[KeithS]

Hours of WHAT per day per mile/? Is there some text to expand on this thought? I don't get it.

 

[Mike]

CRB,

If that is a general stocked trout stream(ATW) and we are only seeing 5.2 hours per mile per day of fishing pressure from general anglers, it is not likely to stay on the stocking list very long. The average fishing trip length on a general stocked trout stream is 3 to 3.2 hrs, so that mile of stream is only receiving about 1.7 trips per day.

 

[pcray1231]

And there are streams where that's all it could handle. Though the assumptions for that lowest number are:

1. All anglers are 100% catch and keep.
2. Average catch rate consistent.
3. Has that level of pressure EVERY day.

So, for instance, if there are days where there are fewer or shorter trips than average, that then allows days where there are more or longer trips.

If, out of those trips, half the anglers release their catch, then that 1.7 goes up considerably.

Even among the catch and keep types, this assumes they keep 100% of their catch. It's pretty common for "keepers" to only keep on occasion. Such as only on some outings. Or be happy with 2 or 3 and release the rest. Or catch 4, release a bunch, and then keep one to quit on. All of these would increase the amount of "trips".

And you use the term "general angling population". But your 1.7 number is based on ONLY the most damaging group. The reality is that group (catch & keep 100% of the time) is a small minority of the general angling population.

And of course, something like the above would be a snapshot of 1 stream. Different streams are going to be very different.

I won't vouch for the numbers, I think it's used as an example. I have my doubts if barbless bait is 4 times as good as just bait, or that barbless flies are almost twice as good as flies. And those measures too are going to vary. The differentials will be different for 7 inch brookies vs. 24 inch steelhead. In terms of bait, there's a big difference between powerbait suspended from bottom on a rod sitting on a forked stick vs., say, actively working a live minnow.

But nonetheless, it is a logical approach to the way things should be looked at. And highlights that ALL angling methods have impact, but some have significantly more impact.

 

[troutbert]

I read the OP and don't what it's supposed to mean. It needs some explanation.

 

[pcray1231]

It's a comparative impact measure of different types of fishing pressure.

 

[BrookieChaser]

Mike wrote:
CRB,

If that is a general stocked trout stream(ATW) and we are only seeing 5.2 hours per mile per day of fishing pressure from general anglers, it is not likely to stay on the stocking list very long. The average fishing trip length on a general stocked trout stream is 3 to 3.2 hrs, so that mile of stream is only receiving about 1.7 trips per day.

This is what information is needed, taken out of context (just provided the figure) one is left to assume the length of trip and/or number of anglers.

 

[troutbert]

The OP post uses this phrase: "Sustainable fishing pressure"

But there is no explanation of what that is supposed to mean.

 

[geebee]

no i get it.

what the Phd is saying, that stream x can tolerate 5.2hrs per mile of catch and keep fishing OR one of the other options like 203 hrs of C&R with barbless flies.

he's basically saying that 1.7 guys fishing every day can clean a mile of stream out - which we already know...

but that 67 FFO C&R guys per mile would also clean out the stream through the average mortality rate for C&R Trout.

its basically saying what fishing effort stream x can support.

i get it, but not sure what use it is....


we know already that put and take fish are short lived and C&R fish die out eventually.

which i'm going to guess the PFBC also know, which is why they stock larger numbers of fish in ATW stretches than FFO on the same river.

 

[pcray1231]

The OP post uses this phrase: "Sustainable fishing pressure".

Yeah, there's no definition there. As in where do you draw the line and say this much is ok, but this is too much?

Nonetheless, I think the intent is not to define a line, but rather, to draw a comparative measure, and consider using some sort of similar comparative measure into regulation.

The part I took exception to was Mike's response:

If that is a general stocked trout stream(ATW) and we are only seeing 5.2 hours per mile per day of fishing pressure from general anglers.

NO!

It would fit if every single angler on that stream were catch & keep all the time.

But the general angling public includes some mix of all of them, does it not? As well as many "tweener" categories not addressed. Like "keep occasionally, but primarily C&R".

I've seen stats from the PFBC that it's a very small % of anglers who keep everything. So if you were to take an overall average of the angling public to be the "general angler", that starting number Mike should use is well higher than 5.2. And really, it shouldn't be by the "average angler", it should be by the "average angler hour". i.e. if catch & keepers make up 25% of the angling public by number, but only 3% of the angler hours, then their contribution to this average should be only weighted 3%. Likewise, if C&R fly fishermen make up 3% of the anglers, but 25% of the angling hours, their contribution should be weighted 25% towards that average.

And even that is just a snapshot, and not necessarily accurate for any particular stream. Most streams may be able to handle much more, or less. I think they're shooting for "concept" here.

What I think could come out of this is, for instance, different priced licenses for various impact levels. i.e. you could have a harvest license and a C&R license separately. You could have an artificials license and a bait license.

In a perfect world, you could also have yearly harvest limits instead of daily ones. Or price according to hours used. But I don't know that something like that could be enforced. Considering that I'm 34 years old, have fished for trout regularly since I was 5 or so, and HAVE NEVER SEEN A WCO IN THE FIELD.

 

[PennKev]

These stats need context.

Where, when, how.

Was this a controlled environment? etc.

I agree with PC about the barbless thing. Personally I have been against barbless regs because I' don't believe they off a significant benefit to the fish in return for increased regulations, however if these stats were the norm and could be proven to be true across several studies I would be willing to change my opinion. All the other statistics I've seen have not shown a definitive benefit to barbless hooks (increased survival greater than a few percent).

Kev

 

[tomitrout]

I think this all means that cabin fever has reached its peak..

 

[pcray1231]

I agree with PC about the barbless thing. Personally I have been against barbless regs because I' don't believe they off a significant benefit to the fish in return for increased regulations.....All the other statistics I've seen have not shown a definitive benefit to barbless hooks (increased survival greater than a few percent).

These numbers can play tricks on your head, though.

Fly fishing = 110
Barbless fly fishing = 203

Barbless is nearly double as good, right? Well, yes. But put this into perspective.

Catch & keep is 100% mortality and is a 5.2. That means if you assume equal catch rates, you can divide the # by 5.2 and get the % mortality.

When fly fishing, according to this, about 1 in 21 fish die. Ok, I can accept that. But when barbless fly fishing, only 1 in 39 die.

Put another way, consider a group of barbed fly fishermen, barbless fly fishermen, and 100% catch and keep fisherment. Each group catches 100 fish.

Catch & keepers: Kill 100 fish.
Barbed fly fishermen: Kill 4.8 fish.
Barbless fly fishermen: 2.6 fish.

Likewise, to double their rating. Take the catch & keepers, convince them to release half their catch. From a 5.2 to a 10.4 on the scale.

Save 50 fish.

Convince barbed fly guys to go barbless. From a 110 to a 203 on the scale.

Save 2.2 fish.

Halfing a high number has a big impact. Halfing a low number, not so much....

 

[PennKev]

I get what you are saying but the the OP is too vague for it to be be easily understood what in the heck is being stated and how each number corresponds to the next.

This thread has hot mess potential so carry on all.

 

[CRB]

"
Table 1: Sustainable fishing pressure on hypothetical Stream X
Regulation................................................hours per day per mile
catch-and-keep......................................................5.2

catch-and-release
bait...................................................................15.8
bait, barbless......................................................62.5
flies, and lures....................................................110.1
flies and lures, barbless.......................................203.3

"
using this study:

" hypothetical stream x with 1000 catch-able trout per mile per mile at beginning of the fishing season. biologists use a general rule of thumb that 50% of those fish will die of natural causes over the next year. In some locations the mortality can be up to 85%.
if angling mortality approaches or exceeds natural mortality, the effect becomes additive and population declines. A switch to catch and release in this example will have no effect on the population unless angling mortality reaches 500 fish.
Assuming a fishing season of 270 days, and a compensatory mortality of 500 fish, 1.85 fish can be killed per mile with out seriously reducing the population(500/270=1.85).
Under catch and keep with a success rate .35 fish per hour, the steam could sustain about 5.25 hours of fishing per mile per day(5.25x.35=1.87) on average or about one angler keeping per mile. Catch and keep regulations could decimate stream x's population under fairly low pressure.""

"It would seam to be impossible to over fish stream x under catch and release, barbless hook, flies and lures only regulations. Assuming an eight hour fishing day, stream x could sustain over 25 fisherman per mile each day of a long 270 day season(203.3/8=25.4) That would be a crowded stream. Fishing with barbless artificial bait would allow 8 fisherman per mile per day,"

Something to think about.