I'm convinced the only 100 percent way to sex any fish species is the presence of sex products such as milt or eggs during spawning season. I had a biologist, Bobby Glennon, that works for Malone and sons, tell me the same.
I have a pond now that was supposed to be all female yellow perch that now has yellow perch reproduction, that may have been due to sexing yellow perch off season, by their urogenital appearance -- even though I was extremely selective and planted only females -- that were textbook in appearance. However in all fairness, it may have also been due to a fish that jumped out of a cage when I was sorting! It only takes one male!
We already know there are bluegills known as "sneaker males" that disquise themselves as females to quickly make their way into a large male's spawning bed to fertilize eggs.
In the human species we have individual that could go either way as far as outward appearance. (Anybody remember Pat on Saturday Night Live?) Who's to say that doesn't happen in the animal kingdom?
Btw I will salvage all the female perch once again next spring and drain the pond down to virtually nothing and rotenone the puddles. Fortunately I have two small ponds I can hold the fish in until the pond refills! The bluegills won't be an issue as they are still all males.
I also have a well to fill the pond back up!
Last edited by Cecil Baird1; 03/27/16 10:54 AM.
