American bullfrogs (Lithobates catesbeianus or Rana catesbeiana) are up to 8” long terrestrial amphibians native to the eastern United States. Within the last hundred years, they have also been introduced to the western United States as an invasive species. These frogs are green-brown, have pale bellies, and may or may not have a subtle darker pattern. Other colors/patterns, such as albino, have been produced in captivity.
Although they can be bitey and have a low tolerance for handling, American bullfrogs are considered to be a suitable pet for beginners.
American bullfrogs are large and capable of jumping a distance of several feet. For this reason, they require a large enclosure. A 40 gallon tank (36”x18”x16”) or equivalent sized plastic tub is the absolute minimum size for a single American Bullfrog; a larger enclosure is preferred. Although American Bullfrogs don’t climb, it’s important that the enclosure have a lid to keep other animals or curious children out.
American Bullfrogs may have a hard time in a standard aquarium due to the transparent walls and may injure themselves trying to escape. Covering three of the four walls with an opaque material like construction paper helps with this problem. It also helps to provide multiple places in the enclosure where the frog can hide.
In order to provide the high humidity needed, use a coconut fiber or soil-based substrate like Zoo Med Reptisoil. The substrate and cage should be kept moist rather than soaking wet through judicious misting 2x/day to maintain humidity levels between 60-80%.
The cage should also have a large aquatic area deep enough for the frog to completely submerge itself. The water should be replaced regularly or have a high quality filter to keep the water clean. Either way, the water in the aquatic area should be appropriately dechlorinated and kept clean of feces or other things that may foul it. Reptile/amphibian water conditioners can work well for making tap water safe for your frog. Do not use distilled water.
Heating and Lighting
American bullfrogs benefit from a low-intensity UVB lamp such as the Zoo Med T8 Reptisun 5.0, half the length of the enclosure and mounted on top of the lid. UVB bulbs decay over time, so make sure to replace the bulb every 6 months.
American Bullfrogs are most comfortable at a temperature range of 72-85F with a nighttime drop to the low to mid 70’s. Most of the year they can be maintained at room temperature without additional heat. In climates where additional heat is necessary, use a couple of low-wattage ceramic heat emitters to warm the air. You will need a thermostat to make sure they don’t get too hot. An aquarium heater should be used in the water as well to maintain temperatures in the mid to upper 70’s.
Food and Supplementation
American bullfrogs will eat anything they can fit in their mouths. They primarily eat a variety of bugs and worms, including but not limited to mealworms, crickets, silkworms, hornworms, superworms, dubia roaches, and other roaches. They may be fed small mice on occasion, although this should not be a frequent occurrence since they are high in calories and can lead to obesity. They can also eat fish that are released into the frog’s swimming area.
Young frogs can start with ¼” crickets or dubias, or small mealworms and progress to full-sized mealworms and crickets, and adult dubias. Provide as large of a variety of appropriately-sized insects as possible. Do not leave prey in the enclosure for long periods of time, as they may bite your frog (as is especially the case with crickets).
American bullfrogs require calcium to build strong bones, vitamin D3 to metabolize the calcium, and a variety of other vitamins and minerals for other body processes. Even if UVB lighting is provided, they will still need a good vitamin and mineral supplement. Dust their prey twice a week Repashy CalciumPlus LoD.
*This care sheet contains only very basic information. If you are new to American bullfrogs, please do additional research to obtain additional information from more detailed care sheets.