How does one satisfy a 9 pound amphibian!?”
Although African bullfrogs are among the most popular and long-lived (to 50 years) of amphibian pets, there remains some confusion as to their proper diet in captivity. Prompted by recent blog inquiries, I thought I’d set down a few thoughts on the subject.
Calcium Through Cannibalism
African bullfrogs, especially growing animals, seem to require a great deal of calcium. Perhaps this is due to their naturally fast growth rate – in their native southern Africa, breeding ponds dry quickly and tadpoles must transform quickly if they are to survive. The froglets then have but a short time to gorge upon enough food to sustain themselves through aestivation periods (dry weather dormancy) that may reach a year in length.
Often, the main source of food for the small metamorphs (transforming frogs) is other African bullfrogs. There is evidence that frogs will preferentially prey upon unrelated individuals, but in any case a diet so high in vertebrates is quite unusual for amphibians.
The Perils of a Rodent-Based Diet
Captive amphibians that are fed vertebrate-rich diets, usually in the form of mice, often develop eye (lipid deposits), kidney and liver problems. Although African bullfrogs do feed heavily upon other frogs in the wild, the practice of feeding captives largely upon mice, while a convenient way of sating these huge fellows, is not advisable.
Outside of the breeding season, the diet in the wild consists mainly of locusts, spiders, beetles, scorpions and other invertebrates…the vertebrates that are taken are more likely to be lizards, snakes and frogs than mammals. In some cases, rodent-based captive diets have not led to problems, but hair impactions and obesity-related health complications have resulted in others.
Providing a Healthful, Varied Diet
Fish and Crayfish
I prefer using goldfish, minnows and shiners for the vertebrate portion of African bullfrog diets, (the bones are an excellent calcium source), with only an occasional pink (un-furred mouse) being provided. Crayfishes, if available, are a fine food item and good calcium source. Neither of these food items is likely encountered by African bullfrogs in their native habitat – crayfish are not native to Africa, although 1 North American species is introduced, and the frogs tend to breed in fishless, temporary pools – but both have proven very useful in the long-term maintenance of this species.
Earthworms and Nightcrawlers
Earthworms, including nightcrawlers for adult frogs, are an excellent source of nutrition, and can comprise a majority of the food offered. The earthworm’s calcium: phosphorus ratio has been shown to generally hover around 2:1, which is ideal as regards frog diets. I believe that earthworms from different habitats may vary in this regard, but have none-the-less had very good results with earthworm-based diets over many years.
Commercially Available Insects
The balance of the diet can consist of crickets, roaches, super mealworms, waxworms, tomato hornworms and other commercially available insects. Large roaches (as well as nightcrawlers) present an excellent means of keeping your frog sated without resorting to rodents. For information on keeping and breeding the orange-spotted roach, please see my article “The Orange (or Guyana) Spotted Roach, Blaptica dubia.
Read Feeding Pet African Bullfrogs Pyxicephalus adspersus – Part 2
Can shrimp and salmon be an occasional meal for an African bullfrogs.
I’ve used shrimp…uncleaned when possible -on occasion; marine fish are best avoided (no direct evidence of problems, but some anecdotal) and small, whole fishes rather than pieces of larger fish should be used. best regards, frank
Thank you. Should I do anything to the shrimp before I feed them to my frog.
My pleasure; nothing to do in the way of preparation. But stay with small whole fishes, earthworms and a variety of insects as staple. Zoo Med Horned Frog diet is also worth a try. Happy, healthy holidays. Frank
Ok, I’ve just been looking for other varieties to feed. I guess as an occasional treat.
I normally do dubai roaches, since we have our own colony. I also do crickets, earthworms and super worms regularly.
I wouldn’t bother as a treat…your diet is good as a basis; no info on long term use of marine species. Be sure to offer whole minnows, oc. pink, crayfish if available, as their CA needs are high. Limit super mealworms; earthworms, roaches very good. Can order silkworms, hornworms. Some other ideas below, let me know if you need anything, best, Frank
Should I limit intake of fish, shrimp or crayfish. I ask just because I’m asking about the African bullfrog specifically.
Thank you for answering all the questions. I really trust this site. So I like to get raw info from you when I can.
Thx for the kind words. Limit shrimp; minnows, shiners and crayfish fine as reg part of diet; goldfish implicated in health probs in some turtles, best to use sparingly just in case, best, Frank
Hey Frank, I’m back a year later with more questions. I hope you have been well and have a moment to help me out.
So my African bullfrog has been growing and overall doing well. But recently in the last month or so he’s buried all the time.
I recently moved, on Jan 1st, and I have not seen him above ground once since I moved. I check on him weekly now just to make sure he is alright.
He has done this before but never this long. He did it for a few weeks last winter also and I just left him alone and fed him the second I seen him out.
I got him out when I moved and he ate some Dubai roaches but that was the last time he was out. He was also buried a while before I moved. I just try to leave crickets and roaches available just in case he’s coming out and I do not see him. Any advice? Am I overreacting?
Temp 80-90 maybe 95. Humidity 50-70 always has water available and his substrate is a mossy blend on top of aquarium rocks.