sexing jacks

[twillight75]

I've heard that make jacks have longer and more pointed dorsal and anal fins. I have 2 large jacks and 2 small ones in a 55 gal. They all get along just fine. I've been trying to get at least an indication which are males and which are females. I even turned up the temp to 81 F. the other day and hoping to see some change in behavior. If anyone has some jack pics of males and females would you please send them to me at twillight75@msn.com. I'd be intrested to see just what they are supposed to look like.

 

[Tiger15]

You can only reliably pick male and female when Jacks are about 3 inch size. One trick I learned to distinquish male and female is to look at the head region from the front. Female has green streaks on the lower part of the gill covers. Male has none. So if you pick male from more colorful head region, you will mistakenly pick the female. Overall, the male has more color, more spots and more pointed fins on the body. Do a search on Jack Dampsey and you'll will find tons of photos.