1. Dark Spot: Look for a dark gravid spot on the belly of the female guppy. It is located towards the rear end and close to the anal fin. As pregnancy advances, the spot becomes larger and changes from a light grey or yellow to a darker color, usually black or brown.
2. Increase in Size: Pregnant female guppies will typically become noticeably bigger as they carry their developing fry inside. The belly area tends to swell and appears round or boxy.
3. Behavioral Changes: Pregnant guppies often display behavioral changes. They may spend more time hiding in plants or around the edges of the tank, seeking cover and protection. You might also notice them resting more frequently on the bottom or the substrate.
4. Loss of Coloration: Some pregnant female guppies experience a temporary loss or dullness of their usual coloration. This can make them appear less vivid or pale compared to non-pregnant females.
5. Increased Appetite: In preparation for the energy demands of reproduction and nourishing their developing young, pregnant guppies often exhibit an increased appetite. They may eat more frequently or seem hungrier than usual.
6. Gestation Period: The gestation period for guppy fish varies but generally lasts around 21 to 28 days. As the due date approaches, all the signs of pregnancy mentioned above become more pronounced, with the gravid spot becoming especially dark and easily noticeable.
If you observe these signs in your female guppy, it is likely she is pregnant and getting close to giving birth. Providing a suitable birthing environment with hiding places and a clean water source will help ensure a healthy and successful birthing process.