I'd only like to keep a few males this spring. What's the main difference in appearance between the 2 sexes?

Males generally have pronounced "white chins" and a more angular head. Since this is spring spawn time, most of the males will squirt all over the deck of your boat, and the females may be dribbling eggs all over as well.

Squirting, dribbling, tog, you're getting me excited:).

Set my green crab trap out Monday , checked it this pm,,, gone, some SOB stole it! Grrrrrr

That sucks, I had a few eel traps stolen back in the day, you would think there would be some respect among fellow fishermen.

I HAD THEM STOLEN LAST YEAR .BRAND NEW ..ONE OVER NIGHT .GONE ,., now where kill a few hours but work drop traps <><

hy green crabs in the spring >>>>>>> I,ll smoke ya without havin any >><.:uhuh:

Joe ya don,t f u ckin know what a female looks like by now ????????????????????? sorry to hear that ><><

I HAD THEM STOLEN LAST YEAR .BRAND NEW ..ONE OVER NIGHT .GONE ,., now where kill a few hours but work drop traps <><

hy green crabs in the spring >>>>>>> I,ll smoke ya without havin any >><.:uhuh:

Joe ya don,t f u ckin know what a female looks like by now ????????????????????? sorry to hear that ><><

No doubt! :-)

Squeeze em a couple times, the males start breathing hard

From our resident expert Dr Tautog:

In general, the female has a pointed profile where as the male lower jaw is square.