Guppy fish are prolific livebearers and can usually give birth to five to thirty fry. Guppies have a gestation period of 21-30 days although the actual number can vary depending on several factors.
Baby guppies are born curled up like small balls (see video at end of the article). This is the same position in which they matured in the female’s womb. Once exposed to water, they will uncurl and begin swimming.
A sign of a healthy batch of newborn guppies is that they swim upward while unhealthy, underdeveloped, or stillborn fry will sink. Fun fact, adult guppies also eat the fry so you may need to separate them.
How To Tell If Guppy Is Pregnant
Pregnant female guppies have expanded and blackened gravid spots near their anal vents. Just before birth, you can see the tiny eyes of the fry through the translucent skin in this area of the female’s body.
The gestation period usually lasts between 21 and 30 days. However, it varies considerably depending on the species of guppies. The good news is that they typically give birth several times throughout their lifespan.
Other things like the tank’s temperature, cleanliness, and the female’s overall health can influence a guppy’s gestation period. These factors along with feeding also influence the size of your guppies.
Taking into consideration the tank conditions, the gestation period for guppies is somewhere from 25 days up to 35. The water parameters, the female’s health and the food supply all influence the duration. On average, 22 to 26 days is the norm for most guppy fish.
Guppy Behavior Before Giving Birth
When a guppy is about to give birth, there are a few telltale signs of a guppy about to go into labor to help you decide when its time to separate her from the rest of the school.
- Female guppy may hide between grass or in the corners of the tank.
- The female guppy will seclude herself from the rest of the guppies.
- A few days before giving birth, the belly of the female will develop an angular shape.
- Change in eating habits, such as refusing to eat or spitting food out.
- Trembling or quivering motions during contractions.
Female guppies can store the sperm of a male guppy for up to 8 months. Hence, it’s possible for a guppy to breed without any males in a tank if it had recently mated.
As your baby guppies grow, be sure to feed them a mixture of vegetables, flakes, and larvae. Baby brine shrimp and vinegar eels are good starter food for newborns.