I'm often asked how to tell Male from Female in tautog/blackfish. Dedicated tog fishers suppose it's better to take males & leave females. Given what I know about tog, I believe that's true -- at least to a point. Probably best to release some big males too..
Because we sometimes find an inordinate amount of male tog over a structure/reef/wreck with very few females; and, as Big Sam Beauchamp, (the most dedicated tog fisherman I ever knew,) noted to me years ago; where there are very large male tog, there are never these inordinate numbers of smaller males with very few females: it appears, therefore, that male tog are territorial with a "bull & harem" spawning behavior.
Do the biggest bull tog run off the little rats? Seems so..
Some great science wiating to happen there.
Then too, because our region's tautog are shown to be virtually stationary/non-migratory - and have even stayed on new/different structure when I've tagged & moved them from another reef for the purpose of studying habitat fidelity: because of this extreme habitat fidelity tautog would make an excellent choice for put & take hatchery work with a university or state program. Anglers & ecosystems would benefit where the work was done & not hundreds or a few miles away.
If I'm correct about the fidelity I've observed from tag returns; a municipality, city, county, or state could 'stock' a jetty or other nearshore area and boost angler success with absolutely no harm to the natural population.
Back to sexing tautog.. Males have a greyish cast above and a fairly clean lateral line with white below. They'll often have a white 'dot' midway in the flank. Sometimes there are two or even three dots. And sometimes no such mark is evident. (see pic)
Male tog also have a squared-off chin. It can jut out further than the mouth in the largest bulls.
Females have a brownish mottled/camouflaged cast all over with no well-defined lateral line. Their chin is a slightly curved slope from the pelvic fins up to the lower lip..
Unlike most fisheries, what we take today will influence the fishery 15 & 20 years from now. By building lots of habitat & allowing as much spawning as possible, it's certainly conceivable our best tog fishing lies in the future
..but that's a mighty high hurdle.
Male tog with well-defined lateral line, square chin, & white dot amidship - See also male w/no dot.
Female tog brownish camo w/an undefined chin.
Pic of a male tog in boulder habitat 20 miles offshore. (note hard & soft coral, plus shrubby bryzoa. Substrate alone does not make a reef. Growth, be it coral, mussels, or any number of other stationary animals, is vital to a reef's fishery production & contribution to the marine food web.)