male or female??

Question

8 red bellied prinhas and how to understand which is male/female?thanks

Answer 1

SEXING AND REPRODUCTION:

The species is not sexually dimorphic. Breeders of piranhas in the home aquarium note visual differences between the sexes, but this scrutiny is limited to fish that are observed for a period of time, up to and including pre-spawning activity. Then some differences can be noted, but subtle due to such activity. References to body girth or coloration is limited to the female being full of roe and the male in pre-spawning colors. Other references to thickness of first ray of anal or body girth is inconsequential to visually attempt to determine sex when the fish are observed in the wild and in a large group. Therefore it is of no value in determining sexual morphs of the species. I have placed a few links to access breeding information being accomplished by hobbyists below.

P. nattereri seems to have a type of courtship display that involves swimming in circles. This results in ventral-to-ventral interactions among the male and female. Eggs are placed in the sediment, in bowl shaped nests. These nests are around 4-5 cm in depth and 15 cm in diameter. The eggs are in clusters and are attached to the bottom vegetation. There may also be a relationship between the times of the spawning and the time of the wet season. (Uetanabaro et al. 1993). The eggs of the piranhas are expelled during spawning and fertilized in the surrounding water. The adult males and females join in partial fertilization. The females are most fertile in the months of April and May. Their breeding habitat tends to be in main bodies of water, such as lagoons (Galvis et al. 1989). A rather large macrophyte population must be present for the young when they are born, so they can feed.

http://www.angelfire.com/biz/piranha038/nattereri.html


From the other info I read, you can only tell when you breed them or disect them ( =O)- though some say that the men are more slender - in the stomach then females due to eggs. This becomes more obvious as they mature and is less obvious - or not at all when young. Also - the males may have a darker color.

Would have to be unfed to look at stomachs or they would look the same.

http://www.aquariumsite.com/fish/red_piranha.php
http://www.piranha-fury.com/pfury/index.php?showtopic=9171

piranha do not have many external differences when it comes to sex, usually the female will be bigger as they mature. but you need a LARGE tank to breed them (250 - 500gal) also there are some sub straight reqs that need to be applied since they build nests (at least red bellies do)

http://www.auspet.com/forum/about8188.html

:o)

Answer 2

Male and female Red-Belly Piranhas are indistinguishable when they are young (length < 5 inches or 12 cm). With maturity, females develop significantly fatter bellies and males become darker, adopting an almost black color.

Answer 3

You better see if under one of its bellies you can see just a hole, that's a female fish. If it has a oblong shaped with a hole, that's the male one. I used to segregate the male "Tilapia" from the female ones when we had a fishpond. My late Dad taught me. May his soul rest in peace, Amen.

Answer 4

Turn on some porn, the ones that are glued to the TV are probably Male...

Answer 5

any slightest male or female resemblance could set the males apart from the females

Answer 6

The male fish has the brightest colors.

Answer 7

its hard to tell..but i think males are a bit smaller

Answer 8

i think it is a male.

Answer 9

the one with the penis is male

Answer 10

males stand up when they pee.