Frogs have four distinct phases in their life cycle: egg, tadpole, tadpole with legs and adult. Each phase requires slightly different conditions for success. Eggs are reared either in a petri dish or in the aquarium that will house the future tadpoles and frogs. Maintain the same temperature of your environment for each phase and provide the appropriate food for the tadpoles and frogs as they grow and mature.
Frogs lay eggs in bunches, ranging from several to several hundred, depending on the species. Prepare your aquarium and habitat before collecting eggs. Fill the aquarium with water and let it sit in the sun for several days. Any chemicals from the tap water will settle out or evaporate. Place gravel, sticks and water plants in the aquarium. Let it develop a natural algae source for tadpole food. In the wild, female frogs lay eggs on leaves and sticks. Cut the leaf and transfer the eggs to your aquarium when ready or purchase eggs from a pet store. Drop the eggs in your aquarium and keep the water at 70 degrees Fahrenheit.
Within 3 weeks, the eggs will hatch into the tadpole phase of the frog's life cycle. Some eggs will hatch within a week of being laid. The tadpoles will eat the algae in your tank and slowly gain mass. Supplement with tadpole pellets from a pet food store or with shredded lettuce. Tadpoles have a large head that tapers to the tail and they resemble small fish without fins. After roughly one month, small legs will form and grow on the tadpole.
Tadpole with Legs
In the third stage of the life cycle, the tadpole develops front legs and shortly thereafter, back legs appear. This happens around the one-month mark in many species but water temperature and species variation affect the rate of development. Cold water slows development while warm water speeds development. A normal water temperature range for frogs is 70-degrees Fahrenheit. Some species transform in as little as one week with others taking months to develop. Monitor your tadpoles for leg development as an indication of the coming adult.
The final phase of the life cycle is the adult frog, which completes the metamorphosis from egg to adult. Provide rocks and dry land space in the aquarium for adult frogs to sit above the water. After their legs develop, frogs will emerge on land where they consume insects. Provide small crickets and mealworms as food for the adults. For a short period of time, frogs retain their tadpole tails while living on dry land. Eventually, the tail will naturally fall off. At this point, either keep the frogs in the existing habitat or release them back into the wild.
Only collect frogs from the wild with permission from your local fish and wildlife agency. Collecting frogs in areas of endangered species is illegal. Only release the adults into areas where the eggs were collected to prevent their spread to new areas where they might be an invasive species.
Among the numerous species of frogs around the world, some have special habits and characteristics. For example, the South American blue poison dart frog will care for the young. The male cares for the eggs until they hatch and then carries the tadpoles on his back and deposits them in a safe area. The mother deposits infertile eggs as a food source for tadpoles. This gives them an easy calorie source and encourages success in the wild. Although the female cares for tadpoles in the wild, she is not necessary for tadpole success in captivity.