Here is one point I noted from the text:
"We acknowledge that our results have limitations (e.g., low sample sizes for crappie, smallmouth bass, and rock bass; northern pike observations from only two lakes; and a lack of information on prey fish community size structure available in the ecosystem) and, therefore, stress that these are “realized” prey lengths, not “preferred” prey lengths."
That is a big if to be missing on.
It could be that those systems were out of balance (which is common) and that there were not many big BG to eat.
This is certainly an unknown. For LMB samples, however, the size of BG that fit the gape are not that large. Almost all of the LMB predators were less than 16". One has to wonder why the 10" LMB weren't primarily feeding on 3" BG if the 15" LMB were consuming primarily ~3". If 3" LMB are abundant enough to feed 15" LMB, what explanation remains as to why they weren't also abundant for the 10" LMB? If we argue its merely a reflection of abundance (or lack of)... more complicated theories must be constructed to justify why the abundance of 1/4 to 1/3 length prey were not predominately consumed by the smaller predators. Even so, it is unknown and I do think it is far less about "preference" and much more about "opportunity".
