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Old 12-09-2016, 04:10 PM
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Duck Butter Duck Butter is offline
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Quote:
Originally Posted by MathGeek View Post
Yes, our data is a lot better.


Quote:
Originally Posted by MathGeek View Post
We have larger sample sizes, and more accurate weight and length measurements yielding much lower uncertainties.

We've had occasion to compare our original creel survey data with state agencies on a number of occasions. The trends are always similar, but our sample sizes, measurement care, and uniform sampling window yields higher accuracy.

Only an idiot would suggest the 20 redfish LDWF measured from Jan-June 2015 would yield a condition factor estimate as accurate as the 86 redfish we weighed and measured in a 3 week window in May 2015. Similarly, their 15 gram weight measurement accuracy does not compare with our 2 gram uncertainty in weight measurements.

The other challenge with a lot of the LDWF weight measurements for the sport species (specks, reds, etc.) is that they weigh groups of fish rather than individuals. Knowing that a group of ten specks they measured on May 6, 2015 weighed 185 ounces is not near as useful or accurate for assessing fish plumpness as having all 10 weights individually with an accuracy of 2 grams. LDWF measured 50 specks in May 2015, which yields an uncertainty in plumpness of over 3%. We weighed and measured 173 specks in May 2015 yielding an uncertainty in average plumpness of about 0.5%.
A creel survey is NOT in any way shape or form an accurate way to draw conclusions for the overall health of a fisheries or any species. It only shows what is being caught and does not show what is actually in the lake itself.

Only an idiot would suggest otherwise
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