1. Increased Appetite: Pregnant guppies tend to have an increased appetite as they require more nutrients for their developing fry. They may eat more frequently and actively seek out food.
2. Modified Swimming Behavior: As the pregnancy progresses and the belly swells, guppies may display altered swimming patterns. They might move more slowly, have a less streamlined body shape due to the protruding belly, and may spend more time resting near the bottom of the tank.
3. Darker Pigmentation: Some guppy species exhibit a temporary darkening of their coloration, especially around the gravid spot (a dark patch near the belly) as the pregnancy advances. This is not always observed, and the extent of darkening can vary among different guppy strains.
4. Increased Resting: As the pregnancy nears its end, guppies may spend a significant amount of time resting, particularly in sheltered areas of the tank, as they prepare for the birth process.
5. Hiding Behavior: Pregnant guppies might display hiding behavior, seeking shelter from potential predators or aggressive tank mates. They may prefer bushy plants, floating plants, or other hiding places to feel secure.
6. Chasing Males: During pregnancy, female guppies may exhibit what is known as "tail-chasing." They chase after males in an attempt to entice them to mate. This is a natural behavior aimed at ensuring the fertilization of the eggs within the female's body.
7. Gestation Period: The gestation period for guppies typically ranges between 21 to 30 days, depending on the water temperature and the guppy strain. As the pregnant female approaches the end of her gestation, the gravid spot becomes more prominent, indicating that the fry are fully developed and close to being born.
Remember that guppies are relatively peaceful and social fish, and their behavior during pregnancy is influenced by their overall environment, water quality, and tank mates. If you observe any significant deviations from these normal behaviors or signs of distress, it's essential to assess the tank conditions and consult with experienced aquarists or a veterinarian specializing in fish health.