"If non-catchability is an inheritable trait, then why did selected fish that did not prove vulnerable to angling (were not caught) have offspring that were in fact vulnerable to angling?"
The point is over time the catchability of the population of LMB became lower and lower. If the % of catchable LMB decreases from 60% to 20% you have a problem. It is insignificant that some few offspring are catchable. That is even a decreasing % over time as well.
YES. I agree. But we need to take all this in the proper context and present the facts around the paper in a way that the authors would approve. What we are dealing with are varying levels of vulnerability. Also, fishing pressure and learned avoidance also plays an important role and when sufficient will affect catch rates more than the vulnerability described in Philipp, et al. To really understand what is going on requires a great deal of information about a pond's cumulative fishing effort, the vulnerability (as described by Philipp, etal), and finally the population density. They will all affect catch rates. There are ways to double check our conclusions by error feedback. For example, if we have identified the catchable fish by artificial lure angling ... then we can follow with electro-fishing or by fishing with live bait. More knowledge improves understanding, and it may adjust original inferences of population density.
If we just inherently draw the conclusion that the LMB in the pond are uncatchable, what remains to be done? It's kind of the end of the story. What if the population density or biomass density is low? What if the forage proportion of its potential is too large? Please just consider this, if populations of LMB are always excessive, then why did the majority of ponds with LMB in the OK Paper on standing weights have F/Cs > 10 and E_LMBs less than 15%. Why were most imbalanced and forage heavy? They were total kill and these ratios cannot hide behind catchability. This is, of course, not always the path a pond takes ... but when a pond takes this path ... we need to be able to recognize that this has happened. Exaggerated ideas about "non-catchability" definitely gets in the way discovery of this condition. It can cause us to err on the wrong side and perform the wrong management actions.
