Table of Contents
What Do Frogs Eat?
Different Frogs - Same Diet?
It’s common sense that different species of amphibians will have different nutritional requirements. There will even be differences within species between individuals dictated by age, sex, past health conditions, etc. However, there are some commonalities in nutrition that provide a baseline from which to start best practices in the feeding regimen.
For instance, oils and fats are important in amphibian diets, and quantity and quality matter. An excess of lipids in the diet can lead to obesity (just like with people) and general imbalance in respect to protein or other nutrients. Many amphibians are strictly insectivorous and can only digest bugs. Insects range from less than 10% to more than 30% fats on a fresh weight basis and are relatively high in essential fatty acids. That is the good news, that a diet of insects alone will not deprive your pet of needed lipids. But with such a wide range, the conscientious owner needs to know the fat content of the feeder insects offered and to alternate those offerings by pet species to maintain optimum weight and metabolism.
Further, proteins and carbohydrates must be balanced as well. Many amphibian species will lose condition and become sickly at less than 16% dietary protein over time. Some species will thrive at around 25% dietary protein, while others may require as much as 45%, especially as juveniles. Even carbohydrates must be managed. We know that amphibians fed diets with excessive fiber may develop intestinal blockages that can lead to numerous problems, even death.
Minerals are extremely critical, and proper balance is the key. For example, frogs fed crickets raised on a commercial cricket diet then additionally dusted with mineral supplements developed hypercalcemia and tissue mineralization from too much of either dietary calcium or vitamin D3 (more on this below). Sometimes more is not better, and it behooves the careful keeper to pay attention to these details.
Frogs Need Diverse Diets!
Comprehensive research on amphibian nutritional needs in captivity has lagged far behind studies on other vertebrates. What is known is that monotonous diets can lead to early death and persistent (and expensive) illnesses. Reports of poor husbandry practices leading to nutritional deficiencies and toxicities include issues with anorexia, metabolic bone disease, “short tongue syndrome” (reduced ability to capture prey using tongue), neurological and musculoskeletal abnormalities, obesity, gastric overload, renal calculi, and corneal lipidosis.
Some of these issues stem from hypervitaminosis D3 (too much), improper amounts of calcium and phosphorus, hyper and hypovitaminosis A, various B vitamin deficiencies, overfeeding, and high levels of dietary cholesterol. There are many more problems attributable to faulty feeding. These conditions are seldom observed in wild populations due to dietary variability. Instead of ingesting 6 different food species, they may ingest many dozens, and in the tropics, hundreds.
This being established, the rest of this article will focus on the specific needs of several popular pet frog species.
What do Poison Dart Frogs Eat?
Small Crickets and Fruit Flies
Poison dart frogs are strictly insectivores, and will only eat small, live insects. A variety of insects are recommended as usual, but because of this creature’s small size, the two most common types of feeders are flightless fruit flies and very small crickets. The term for dietary habits of this sort is microphagus – a term that indicates that they specialize in eating foods, generally under 1/8″ in size. Because poison dart frogs eat such tiny food items, they need to eat lots of them. A young-adult poison dart frog is capable of eating 50 to 75 fruit flies in a day and should be fed this amount four or five days a week at least.
Note: Although many keepers leave their adult dart frogs with no food for a day or so now and then, some experts recommend daily feeding, due to the nature of this frog’s high activity level and size of food items. Belgian biologist Robert Browne (2009), recommends food items be offered ad libartem, meaning that food should be available to the frog all the time and not just during feeding sessions.
However and whenever you choose to feed your dart frogs, dust food items before every feeding with a high-quality calcium and vitamin supplement, such as Exo Terra’s Calcium Powder Reptile and Amphibian supplement. However, as mentioned above, when feeding tiny pinhead crickets, care must be taken with dusting if the food items are gut-loaded with high phosphorus, high D3 supplements.
Fruit flies are also an excellent staple. There are two kinds on the market.
Drosophila melanogaster measures about 1/16th of an inch long, making them ideal as the staple food for a variety of dart frogs and other animals that prefer smaller prey items. These flies lack wings, and so are flightless.
Drosophila hydei is another common feeder fly that is about twice the size of melanogaster (1/8”). They are ‘meatier’ and a nice item to offer dart frogs that prefer larger prey items. They are roughly similar in nutrition with one exception…they are twice as high in calcium. Dusting should be eliminated when feeding this species. Gut-loading should be maintained.
Many new keepers do not realize that the nutritional value of fruit flies can be enhanced by raising them on a nutritious, high protein gut load. Even though their life spans are extremely short, what they do eat before shuffling off their mortal coil can enhance your pet’s wellness.
Want to add a little pizazz to your dart frog’s daily routine? Then consider springtails. They are high in protein and are cheap and easy to culture. You can raise them on commercial springtail food, or 100% brewer’s yeast. Springtail food is around $3 an ounce, brewer’s yeast is a few pennies. You decide.
And of course, never overlook the value of feeding small pinhead crickets. Easy to keep, inexpensive, and full of nutritious vitamins and minerals when properly gut-loaded and dusted, these items should be a continual mainstay for all varieties of dart frogs.
What Do White’s Tree Frogs Eat?
They can become obese quickly
The type and amount of food your frog needs will vary somewhat, but keep in mind that White's tree frogs tend toward having obesity issues, so do not overfeed. Crickets should be their primary food item.
Gut Load Feeders
As usual, all insects fed to this species must first be gut-loaded with nutritious foods and prey items dusted with a calcium-vitamin supplement. Perform this dusting only once a week for mature frogs, two or three times a week for older juveniles, and daily for very young frogs. Repashy Calcium Plus, RepCal Calcium with D3, and RepCal Herptivite are all acceptable choices that are highly rated by experienced keepers.
Black Soldier Fly Larvae
Black Soldier Fly larvae are sold under a variety of trade names such as Phoenix worms, Repti-Worms, or Calciworms. Black Soldier Fly (BSF) larvae make healthy, nutritious feeders. They are high in calcium and low in phosphorus, and therefore should not be dusted with additional calcium powder, but should be gut loaded.
And Bonus!!! Black Solider Fly larvae also contain lauric acid, which can help kill parasites present in the digestive tract of your pets. However, they are low in fat-soluble vitamins (A, D3, and E). To make BSF larvae a more complete food item, fat-soluble vitamins should either be provided via gut-loading or with a multivitamin dusting supplement.
Researchers on this subject (Boykin and Mitchell, 2020) recommend a “vitamin A concentration of diet between 16,000 and 20,000 mcg retinol equivalents/kg, gut-loading time period of 24 h.” In English… a little goes a long way. Products high in this nutrient are Repashy Vitamin A Plus. This product contains preformed A in the form of retinol, which is safer and more available to the frog's body than beta carotene. Fun fact…when a keeper can find just the right amount of Vitamin A supplement for their gut-load, for either BSF larvae or crickets, the green hue of a White’s skin will get greener, as the body distributes the nutrient throughout the body for metabolic purposes, and then shunts the rest to the melanophores in the frog’s skin. This same principle is true for making your dart frogs oranger and redder as well.
What do Tomato Frogs Eat?
Tomato Frogs Love Variety!
Tomato frogs will only consume live food. They love variety. Crickets can be a mainstay, but frequent supplementation with other food items is highly recommended. They will snarf down small nightcrawlers with glee. Waxworms, mealworms, BSF larva, Reptiworms and fly maggots are all good. Offer these in a continuous rotation. Adults can even be fed pinkies, which will supply more protein and calcium than most insect offerings. They are fattening, however, so no more than once per week is advised. Improper lipids balance such as that leading to obesity and high blood cholesterol has health consequences.
Tomato frogs are particularly susceptible to corneal lipidosis. Whitish plaques, caused by the deposition of cholesterol deposits in the cornea, are characteristic of this disease. They make the frog look as though they have developed cataracts. High cholesterol levels in the blood, which are a result of diets high in fat, are generally believed to be the cause. Treatment is usually ineffective, but correction of the diet may prevent the condition from worsening. Prevention is the best course of action for this ailment.
Vitamin A is Important
As mentioned above, providing plenty of Vitamin A will help to prevent certain nutritional illnesses and make your frog brighter and redder. Researchers have found that adults and young of Dyscophus guineti benefit from beta carotene gut-loaded food items. They demonstrated that Vitamin A from feeder crickets supplemented with beta carotene enhanced soybean oil (measured as retinol) raised plasma retinol concentrations in the test subject tomato frogs. Excess beta carotene seemed to turn the frogs more yellow, so if you like a nice red frog, feed Vitamin A in the manner described for White’s Tree Frogs above.
In addition to aesthetic reasons for providing the correct amount of Vitamin A, low levels can create a condition called squamous metaplasia, which results in the animal’s inability to produce proper sticky mucus on the tongue. When a toad or frog tries to grasp prey, it doesn’t stick to the tongue when it is retracted into the mouth, and the prey gets away.
What do Pacman and Pixie Frogs Eat?
Big Prey for Big Frogs
Both of these species are voracious eaters. Unlike the species above, these guys actually prefer vertebrate food, such as rats, mice, lizards, and small snakes. They will, however, indulge in the common insect feeders, if that is all that is put before them.
Crickets are a good mainstay, but not as good as for the frog species discussed above. Pinkies and fuzzies will need to be offered on a regular basis. Some keepers swear by offering guppies, others say to avoid them.
Will they eat fish?
Feeding fish with tongs to your Pacman or Pixie can be very entertaining. There is no reason not to occasionally. They are not packed with sufficient nutrition to offer very often. But, for a Pacman or Pixie frog suffering from gout, they are a great way to keep them fed without exacerbating the problem. Gout is the deposition of uric acid crystals in various locations within an amphibian’s body. It can be caused by several factors, including diets high in purines, dehydration, infection, and kidney failure. The crystals can form in soft tissues, such as the liver and kidneys, but also form larger stones in the bladder. By the time it is diagnosed, it is often severe. Bladder stones are often successfully removed if the amphibian is in otherwise good condition. It is a very painful condition. Although gout is not extremely common in amphibians, highly carnivorous but sedentary predators that tend to be somewhat inactive much of the time are more prone to excess protein accumulation. The more obese the pet is, the more likely. Therefore, offer guppies every so often in place of high protein foods such as mice or crickets.
Feed only live guppies or mollies. Frozen fish items present a risk of hypovitaminosis B1. This can actually be caused by thiaminase in the prey item. Frozen fish contain this enzyme (National Research Council committee on animal nutrition (NRC), 1993). Fresh fish do not, as it is a result of the freezing process. This enzyme causes a decrease of available thiamine in the feed which may result in vitamin B1 deficiency. Vitamin B1 plays a role in neurological functioning and so deficiency can lead to paralysis, tremors, spindly leg syndrome, and scoliosis. Thiamine deficiency should be considered when fish-eating amphibians present neurological signs. A histology of peripheral nerves will reveal that demyelination of nerve sheaths has occurred. The good news is that if a veterinarian catches this condition early, then a B1 injection followed by feed supplementation and/or changing of the diet can reverse these symptoms and resolve the condition.
Clean their cages frequently
Speaking of protein, a high protein diet that might work well for a bearded dragon can be detrimental to these sorts of amphibians. Unlike most terrestrial organisms such as reptiles which secrete concentrated uric acid or other relatively nontoxic forms of ammonia, nearly all aquatic amphibians excrete nitrogenous waste as ammonia. This mode of waste excretion is energy efficient, however, the waste product is highly toxic and is dependent on a healthy external environment to ensure safe ammonia levels. Since the two species of frogs discussed in this section are only semi-aquatic, a high protein diet can result in a toxic environment for your pet very quickly. A solution to this is to clean frequently or lower the protein content for adult pets by feeding fish and superworms (32% protein) or BSF larva (35%) until any environmental or obesity problems subside. Remember, your amphibian friend absorbs lots of substances through their skin, you don’t want ammonia to be one of those.
Other than those unique considerations, nutritional management is similar to the species mentioned above.
Summary of Common Feeders
As mentioned, crickets are an integral part of the carnivorous frog’s diet. They are an excellent source of protein and other nutrients, as long as they are properly gut-loaded. A formula for making your own inexpensive gut-load that includes plenty of beta carotene can be found on this site. For Pacman frogs, fun smaller prey items can include dubia roaches.
Dubia roaches have softer bodies than crickets which can make it easier for the young big frog to digest. Most Pacman frog keepers and breeders prefer dubia roaches over crickets for these reasons.
Nightcrawlers and Red Wigglers are also popular with big frogs when vertebrate food is not available. Their non-chitinous bodies make them very easy to digest. Never collect these items from the wild, as they will be chock-full of parasites. Bait shops are a no-go as well. Only purchase worms that are specifically offered to the pet trade.
When feeding your frogs, all insects should be dusted with a quality supplemental powder, either a complete calcium, D3, and multivitamin mix such as Reptivite, or create your own supplement regime with calcium and D3 and a multivitamin about once or twice a week. Regular dusting is most important for young, fast-growing frogs - older animals that are closer to adult size need supplements less frequently.
Speaking of D3, Hypovitaminosis D3 (too little) could lead to a shortage of calcium. Hypocalcemia often leads to activation of the parathyroid gland and causes nutritional secondary hyperparathyroidism (NSHP). This is one of the main causes of metabolic bone disease (MBD). Some researchers have identified additional complications in amphibians fed supplemented diets yet still displayed MBD. They concluded this was due to a lack of UVB radiation. Therefore, in captive management one should take notice of both the diet and the environment in preventing MBD.
Care should be taken when supplementing the diet with vitamin D3. The oral requirements for amphibians are largely unknown, which may lead to under or over administration. With too little D3, MBD can develop, yet toxic adverse effects can be possible when too much vitamin D3 is ingested. Frogs suffering from hypervitaminosis D3 will be lethargic and weak, while also suffering from anorexia and edema/ascites (bloating with bodily fluids. In some cases, this can lead to mineralization of the heart and the kidneys, and urea-based kidney disease. Anytime hypervitaminosis is suspected a keeper should immediately alter the diet to prevent further damage. UVB lighting may remain in place, but all calcium supplements should be without D3 added. This advice is true for all of the species mentioned above. Multivitamins should be maintained at their usual weekly dosage, as long as they do not contain D3. It may be 6 months or longer before dietary D3 is advisable.
Don't Let Frogs become Obese
One last word of advice for all of the above species except dart frogs is the tendency to overfeed one’s frogs. Obese frogs are cute in their own way and feeding really voracious species like Pacman and Pixie is half the fun of owning them. Forums are full of keepers who brag about their fat amphibians and how adorable they are. They are putting those cute little pudgies at risk for all kinds of problems, the eye problems mentioned above being just one of those risks. For instance, high levels of fat in the diet can lead to secondary deficiencies. The higher concentration of fat reduces the relative concentration of other nutrients and can cause relative shortages so that in effect the animal is fat appearing but actually malnourished.
The kind of fat in the diet also matters. Saturated fats are as bad for frogs as they are for people, but unsaturated fatty acids are important for the growth and health of your pets. Examples of unsaturated fatty acids are omega-3 fatty acids and omega-6 fatty acids, with omega-3 being the most beneficial. These fatty acids perform a critical function in the transportation of vitamin A into cells. Adequate unsaturated fatty acids can therefore prevent pathologies arising from faulty transport, as critical for the nervous system as Vitamin B1.
If this seems complicated, well, you’re not wrong. It takes a thoughtful and educated approach to amphibian husbandry to know how to get the balances just right. An overarching rule of thumb that will help to prevent problems from arising is variety, variety, variety. This is true for the species mentioned above and many others as well.