DNR volunteer survey results

[BILL H]

Any data that comes out of a voluntary survey such as this one is less than useless. There is no way that it can provide any sort of statistically relevant snapshot of fishing pressure/fishing success. If any one attempts to regulate using this type of information they don't deserve their job.

Scientific info it ain't. It is tough enough to get a valid sample even using robust statistical approaches. But this "feel good" approach doesn't even pass the laugh (or smell) test.

[Bug Guy]

Bill H, I have to respectfully disagree - in my opinion, while the data is not very robust to say the least, it is data and it does have some use. It is biased and the low reporting limits the scope of inference (that is bad) - but some trends can be identified as long as the bias is understood and the conclusions made are limited. Those trends can be used not for decision making about regs, but for decisions about where to focus further studies and surveys. In otherwords, where to spend the limited money they have for more robust, focused studies since surveying the entire MD Chesapeake is out of the DNR's budget (and likely out of their ability).

While, it can easily be misinterpreted or misused on accident or on purpose, data is data, even if small and biased, it is still data. But I think everyone has a legitimate concern about how this data is being used...who knows.

[BILL H]

Bug Guy,
I guess we will have to disagree on this. I am a great believer in the principle of GIGO. And that is exactly what I see here. What we have is a set of data with absolutely no controls on it, and no real way to determine the direction of bias or whether there is bias. I have many problems with the data set, and size is not the only or the greatest one.

Whether you have no data or poor data, you are only at the level of a WAG, and don't even begin to approach even a SWAG. And even though a blind pig can sometimes find an acorn, I don't think we should base natural resource management on that philosophy.

[Bug Guy]

Originally Posted by BILL H

Bug Guy,
...What we have is a set of data with absolutely no controls on it, and no real way to determine the direction of bias or whether there is bias. I have many problems with the data set, and size is not the only or the greatest one....

No doubt nobody can make the kinds of conclusions that can from a replicated study with controls, experimental variables, dependent variables, etc. And making decisions about "effect" from this study would be wrong.

I guess from the data I see pattern. Really, it is a small and poorly done creel survey. This links to a page that I found on a quick google search that does a decent job describing a good survey: http://www.michigan.gov/dnr/0,1607,7...7829--,00.html

For example, the bias comes from the people polled - an unbiased survey would randomize where people fished, what days fished, etc. and take into account other things. In addition, the data would include skunks (as stated previously in this thread). So, this data should take into account these biases and limit any conclusions about pattern to the types of fisherman, location of fisherman, and other variables that describe the respondents. Conclusions on pattern should not be applied to the entire bay. No conclusions on effect to the fish should be made. But, properly done creel surveys (which is what I think the registry will do a better job of) has successfully helped to manage fisheries in other places.

But I will admit - I don't have the greatest confidence that this data is use in the limited form that it should be. So I'm not necessarily disagreeing with everyone here.

[BILL H]

Originally Posted by Bug Guy

No doubt nobody can make the kinds of conclusions that can from a replicated study with controls, experimental variables, dependent variables, etc. And making decisions about "effect" from this study would be wrong.

I guess from the data I see pattern. Really, it is a small and poorly done creel survey. This links to a page that I found on a quick google search that does a decent job describing a good survey: http://www.michigan.gov/dnr/0,1607,7...7829--,00.html

For example, the bias comes from the people polled - an unbiased survey would randomize where people fished, what days fished, etc. and take into account other things. In addition, the data would include skunks (as stated previously in this thread). So, this data should take into account these biases and limit any conclusions about pattern to the types of fisherman, location of fisherman, and other variables that describe the respondents. Conclusions on pattern should not be applied to the entire bay. No conclusions on effect to the fish should be made. But, properly done creel surveys (which is what I think the registry will do a better job of) has successfully helped to manage fisheries in other places.

But I will admit - I don't have the greatest confidence that this data is use in the limited form that it should be. So I'm not necessarily disagreeing with everyone here.

I think we are in agreement far more than any disagreement. I do think that the national registry can serve as an integral part of a pretty good system for estimating fishing effort/success if it is combined with a properly constructed creel survey (which I believe will be a separate "dockside" survey).

The missing randomization is my biggest problem with the voluntary survey. We just don't know whether the respondents fish more or less than the average angler or whether they have more or less success. And there is no way to relate their effort/success to the average effort/success.

I see the voluntary survey is a way for concerned anglers to feel good about providing information on their participation in the sport, but that the information is of extremely limited value beyond the "feel good" aspect.

I believe this cat is sufficiently flat, and I will not run over it again.

[Bug Guy]

Originally Posted by BILL H

I believe this cat is sufficiently flat, and I will not run over it again.

I can agree on that....

& one last thing - oh how nice it was to have a civil discussion without 100 A-holes chiming in to do nothing other than stir the pot and muddle the conversation. Thanks.

[BILL H]

Originally Posted by Bug Guy

I can agree on that....

& one last thing - oh how nice it was to have a civil discussion without 100 A-holes chiming in to do nothing other than stir the pot and muddle the conversation. Thanks.

Uh Oh, you may have opened the floodgates.

I agree, a civil discussion can be a rarity, nowadays.

Originally Posted by BILL H

Any data that comes out of a voluntary survey such as this one is less than useless. There is no way that it can provide any sort of statistically relevant snapshot of fishing pressure/fishing success. If any one attempts to regulate using this type of information they don't deserve their job.

Scientific info it ain't. It is tough enough to get a valid sample even using robust statistical approaches. But this "feel good" approach doesn't even pass the laugh (or smell) test.

Bill H, I agree with you..."less than useless" what kind of idiot would admit to keeping an 11 inch rockfish, let alone the other undersized rockfish claimed to have been kept in the data? This could easily be infiltrated by people looking to shut down the fishery and they could post inaccurate data, especially with such a small sample size that is not representative of 1/100th of a percent of yearly trips that occur on the bay