how to sex yellow labs

[bigbad-ratman]

well, how do you? the only thing i can find on a quick internet search, is that males have more black on their pelvic and anal fin. can anyone throw me clue here? it would be appreciated.

[Lab_Rat]

The black is more a sign of quality breeding than an indication of male or female anymore. The only reliable way to sex them is to vent them when they are large enough.

[kaybee]

Physically both of the genders are near identical. While males "may" have bolder black markings on their anal and pelvic fins, this is not always the case.

One way to figure out gender (with matured specimens) is to vent them. That involves netting and physically examining their openings. This is perhaps the surest means.

However there are other ways to make a good gender judgement without physically inspecting the lab.

One external gender characteristic: the pelvic fins of the males are proportionately larger than those of the females'. Color of the pelvic fins is irrelevent when using this characteristic as a gender indicator.

Note the length of the pelvic fins in relation to the size of this male yellow lab:

Male


Compared with propotionately smaller sized pelvic fins of this mouthbrooding female:

Female


Another method is the behavior to the labs among each other.

While male and female yellow labs may seem identical to the casual human observer, these fish KNOW which among them are males and which are females because they also utilize non-visual cues (pheromones, etc).

Matured male yellow labs will be motivated to challenge, display and even spar with each other. During these face-offs the males, at least the dominant one's, are cleary advertising their gender in attempts to dominate or intimidate rivals. So observation how they interact with other yellow labs can be very revealing. In this way the gender of one yellow can lead to determining the gender of the others.

Additionally, yellow lab interaction with other mbuna's will offer huge clues. For example, here's one of my male yellow labs attempting to assert dominance over an equivalently-sized younger sub-adult red zebra. Red zebras are fairly dominant and aggressive mbuna's; so this action alone tells me: This yellow lab is a male.