Savannah Monitor Food Pyramid
The pyramid is a guide to feed your savannah monitor. You do not have to follow the schedule exactly (see special considerations). It is based off of research on the macronutrient and calcium requirements of various types of reptiles outlined in the Merck Veterinary Manual as well as individual scientific studies about wild savannah monitor diets. This pyramid is also based off of what extremely experienced savannah monitor keepers have found to work for their animals.
The savannah monitor food pyramid is designed to be a user-friendly guide. The diagram in the insect section shows how feeder insects should be properly gut loaded for a savannah monitor. These amounts are proportioned by weight. The key on the right side describes how many times to feed this food group per a week.
This guide is made to combat the incomplete knowledge of savannah monitor nutrition. Many new owners are confused about what to feed their pets while experienced owners are looking for the best diet possible.
There is no realistic way for the in-home keeper to match the wild diet of a savannah monitor. It is conventional wisdom that variety is the key to combat this, but that isn’t always the case. For example, the savannah monitor is adapted to eating an extremely low fat diet, while mice have a comparatively high fat content.
The most important thing in any animal’s diet is feeding appropriate foods in appropriate ratios in order to get the correct balance of protein fat and carbohydrates. It will also help you understand other nutrients how to get them too.
Key Food Groups:
Vertebrate prey is a source of protein for savannah monitors, but is consumed slightly less than insects in the wild. However, in captivity whole prey is the most important food group for savannah monitors. This is because whole prey items include organ meat and bones which as essential for providing vitamins and minerals.
Frogs are their exclusive source of vertebrate prey and consist of 40% of the wild savannah monitor diet by weight (Losos and Greene 1988). Other studies have indicated that frogs are the only vertebrate prey but only consist of 5% of prey items (Bennett 2000). It is important to note that these counts were by prey item not by weight. If 5% of prey items consumed were frogs, this would account for a much larger portion of the diet by weight. Ideally, this diet would be mimicked in captivity by feeding whole captive-raised frogs to the savannah monitor as an exclusive vertebrate source. However, this simply isn't a practical feeding solution for most keepers. It is also important to note that wild frogs can often be infected with parasites and should never be fed to reptiles.
Frogs are extremely lean compared to mammals. This indicates that the savannah monitor's liver is not adapted to handle a large portion of fat in the diet. Whole prey such as day-old chicks are recommended over mice and rats because of their lower fat content.
Whole, lean, freshwater fish are also a good food choice for savannah monitors. The carp, goldfish and minnow family should be excluded due to high thiaminase content, which unfortunately are the most common feeder fish available. Whole sunfish and perch are the most practical options to feed whole, lean, freshwater fish, but may need to be wild caught as they are difficult to find in stores. Rainbow trout are higher in fat content, but are often available as whole fish in grocery stores.
All of this information is not to say that mice and rats should never be fed to a savannah monitor. Many healthy animals have had these food items as a large portion of their diet. It is simply important to be aware of the limitations of these food items. If feeding a mice or rat heavy diet, balance it out with lean foods.
Lean White Meat:
Lean meat is crucial to balance out the inherent fat content of whole prey items. Even day-old chicks have 2-4x the fat content of a frog. In order to prevent fatty liver and obesity in the savannah monitor it is wise to add a lean meat source such as commercially raised frog legs, chicken breast, turkey breast (ground turkey is too high in fat content) or even walleye and pike. Lean white meat source should only be a small supplement to whole prey items and consist of less than 1/3 of vertebrate foods.
Insects are the main food source for savannah monitors. Most commercially raised insects are deficient in several nutrients, including calcium, thiamin (vitamin B1), vitamin A and vitamin E. It is necessary to feed the insects a high calcium and vitamin A diet before feeding to your savannah monitor. Gut loading is much more effective than dusting insects. The insects fed should also be low in fat content.
About 70% of the insects a savannah monitor eats in the wild are in the grasshopper/cricket family (Losos and Greene 1988). This was corroborated by Bennett (2000) who could that 85% of all prey items were in the grasshopper/cricket family. It is also interesting to note that juvenile savannah monitors share a burrow with the giant cricket and feed heavily on this species (Bennett "Observations" 2000).
Savannah monitors, however, do not need crickets/grasshoppers as an exclusive insect source, even in the wild. Studies of other savannah monitor populations have found that their primary prey items are in the beetle family (Cisse 1972). Scorpions, moths/butterflies and snails also are natural prey items for the savannah monitor (Losos and Green 1988 and Bennett 2000). This indicates that in captivity these animals are highly adaptable to any insect prey item.
Ideal insects include crickets, grasshoppers, roaches, hornworms and soldier fly larva (reptiworms). Insects that should be fed more sparingly due to their fat content include mealworms , superworms and waxworms.
Check out the nutritional analysis of some common feeder insects.
Insects' Diet- Gut Loading:
Gut loading insects is critical for all savannah monitors because so much of their diet comes from insects. The food for gut loading should be 20% calcium, 50% greens, 10% vitamin/mineral supplement and 20% vegetables, by weight.
-Calcium (20% of gut loading diet):
A calcium supplement should be purchased separately from a vitamin and mineral supplement. Almost all feeder insects are deficient in calcium and calcium is required more than any other mineral in reptiles. The calcium supplement fed to insects should include vitamin D3 to ensure that the insects can process the calcium.
The calcium recommendations for gut loading are based on the Finke (2003) study that recommends 3-9% elemental calcium in a gut loading diet, depending on the insect species. Calcium carbonate (the most common calcium supplement) is 40% elemental calcium, thus 20% calcium supplement is needed in the diet. This recommendation is also backed up by Finke et al. (2005), which showed that 15% calcium carbonate supplementation to the gut loading diet increased the calcium content of small crickets from 0.2% to 1.1% calcium. Considering that the 20% calcium supplement amount is by weight, it actually won't appear to be as much calcium as you would expect. It is highly recommended you weigh out the ingredients in your gut loading diet.
-Vitamin/Mineral Supplement (10% of gut loading diet):
A vitamin and mineral supplement is essential when feeding insects to ensure no nutrients are missing, however there is quite a variety of supplements on the market. When looking for a supplement for a healthy gut loading plan, as outlined here, there are a few key nutrients one should consider. Most insects are low in magnesium, iron, iodine and vitamin E. Make sure your supplement provides these nutrients as well as ample amounts of B vitamins. Often iodide is provided using kelp as an ingredient. Vitamin A is also a nutrient commonly lacking from commercially raised insects. A vitamin and mineral supplement can be used to help increase the vitamin A content of a gut loading diet, but if fed the correct vegetables in the gut loading diet, this is not required.
Greens (50% of gut loading diet):
Greens provide moisture, bulk and vitamins to a gut loading diet. Greens generally can be divided into three categories, staple, occasional rare and never foods. To make a green an every day green it must be rich in nutrients like calcium, low in phosphorus and low in anti-nutrients like oxalates and goitrogens. Occasional greens are rich in nutrients, but contain too high a level of oxalates or goitrogens to be feed every day. Rare greens have very high oxalates and goitrogens. They should be avoided. Never greens have high phosphorus, low calcium and sometimes have high oxalates.
Staple greens are escarole, endive, alfalfa and dandelion greens.
Occasional greens are bok choy, collard greens, mustard greens, turnip greens, watercress
Rare greens are kale, dark lettuces, parsley, swiss chard, spinach
Never greens are iceburg lettuce, cabbage
Vegetables (20% of gut loading diet):
Vegetables are critically important for gut loading as a source of beta-carotene, which is processed by the insects into retinol, a form of vitamin A that savannah monitors can use. Good vegetables are often bright in color and not too high in oxalates and phosphorus. Sometimes the healthiest foods are also the strangest, such as prickly pear leafs and hibiscus flowers.
Some of the best vegetables include acorn squash, butternut squash, bell peppers, prickly pear leafs, hibiscus, common button mushroom, okra, and pumpkin.
Other good vegetables include asparagus, broccoli, brussel sprouts, carrot, green beans, snap peas, tomato, yellow squash and cucumber.
Check out the nutritional analysis of vegetables.
Bennett, Daniel. Observations on Bosc's Monitor Lizard (Varanus exanthematicus) in the Wild. Bulletin of Chicago Herpetological Society. 35(8):177-180 (2000).
Bennett, Daniel. Preliminary Data on the Diet of Juvenile Varanus exanthematicus (Sauria: Varanidae) in the Costal Plain of Ghana. Herpetological Journal. 10 75-76 (2000).
Cisse, M. (1972). L' Alimentation des Varanies au Senegal. Bull. L'inst. Fondam. Afr. Noire. Ser. 39 503-513 (1972).
Finke, Mark D. Gut Loading to Enhance the Nutrient Content of Insets as Food for Reptiles: A Mathematical Approach. Zoo Biology. 22(2):147-162 (2003).
Finke, Mark D., Shari U, Dunham and Christabel A. Kwabi, Evaluation of Four Dry Commercial Gut Loading Products for Improving the Calcium Content of Crickets, Acheta domestics. Journal of Herpetological Medicine and Surgery. 15(1) 7-12 (2005).
Losos, Jonathan B., and Harry Greene, Ecological and Evolutionary Implication of Diet in Monitor Lizards. Biological Journal of the Linnean Society. 35: 379-407 (1988).
These dietary guidelines are designed for an average, healthy, savannah monitor. As with anything, if your reptiles are ill you need to consult a veterinarian for advice. That being said, there are some normal dietary considerations that apply to many savannah monitors. If your savannah monitor is sick, please check out our diagnostics page.
Many captive animals of all kinds suffer from obesity. Ensure that temperatures are warm enough in the enclosure to keep metabolism high. The best thing you can do for an obese savannah monitor is feed a larger proportion of lean insects and lean meats in the diet. It is also wise to slowly reduce the amount fed. Obesity is deadly. It can cause liver failure and many other issues. Supplementing with a very small amount of omega 3 fish oil is also wise to prevent liver disease in obese animals.
Juveniles and Breeding Females:
Young savannah monitors are growing fast and need more protein and calcium than older savannah monitors. These animals should be fed every day and as much as they want to eat. It is wise to increase the amount of whole prey offered to them. Fatty insects are also a good source of energy for young animals. Make sure all insects fed are gut loaded with calcium. This also applies to females developing eggs, known as gravid females.
Not eating is a common occurrence with many pet reptiles. Usually the issue is with the temperature of the enclosure, or another husbandry problem. Ensure that your tank is up to standards and visit a
veterinarian. In the mean time, remember that eating any food is better than eating no food. Even if all your savannah monitor will eat is pinky mice this is better than not eating anything at all. Work on getting them to eat healthy foods, but again, unhealthy food is better than no food. For tips and tricks to get your animal to eat see our "appetite stimulation" page.
There are many key nutrients in a savannah monitor's diet.
The key nutrients are listed in alphabetical order.
Definition-natural plant flavonoid pigments that appear blue or purple
Function-a weak antioxidant that enhances color
Foods-acai, blood orange, blackberry, raspberry, blueberry, purple grapes
Definition-a red-orange pigment in plants that can be converted by some animals to vitamin A
Function-A vitamin A supplement for omnivores and herbivores that cannot be overdosed as well as an antioxidant that enhances color
Foods-carrot, pumpkin, sweet potato, spinach
Definition-an abundant chemical element that essential for life
Function-building blocks for bones and teeth and an essential element for cell physiology
Foods-calcium carbonate supplement, mice, day-old chicks, soldier fly larva, greens.
Definition-a biological molecule made of chemically linked sugars. Carbohydrates include, sugars, starch and fiber
Function-simple energy source for animals
Foods-almost all foods, especially plants
Definition-a chemical element that is an essential mineral
Function-Copper has many functions, including collagen formation, enzyme cofactors, incorporating iron into red blood cells and generation of energy from carbohydrates. It is usually abundant in foods for crickets and inhibits zinc uptake, so copper in cricket gut loading needs to be limited.
Foods-spinach, turnip greens. asparagus, beans, nuts, kale, mushroom, pumpkin
Definition-a biological molecule that is found in plants and animals
Function- a dense energy source and an energy storage method
Foods-mice, day-old chicks, waxworms, superworms, mealworms,
Fiber - Click Here for More Information
Definition-a type of complex carbohydrate in plants that cannot be digested
Function-Fibers add bulk to the stool and give food for gut bacteria
Foods- all vegetables and fruit
Definition-substances that disrupt the production of thyroid hormones
Function-These anti-nutrients occur in plants should be avoided in excess in order to maintain thyroid health in crickets.
Foods-cassava, soy, peanuts, strawberries, spinach, bok choy, broccoli, cabbage, kale, turnip
Definition-a chemical element abundant in the ocean that is an essential mineral
Function-key component of hormones made by the thyroid
Foods-kelp, ocean fish, shrimp, spirulina, scallops, standard table salt
Definition- A category of nutrients that makes up the bulk of foods. It includes protein, fat(lipids), carbohydrates and water.
Function-each macronutrient has a different function, but protein, fat(lipids) and carbohydrates can all provide energy. The ratios of these nutrients in a diet is extremely important.
Definition-a chemical element that is required by living organisms other than carbon, hydrogen, nitrogen and oxygen
Function-builds bones, tissue, catalyzes biological reactions, transports oxygen and many more
Foods-all foods have some mineral content
Definition-a specific organic acid found in plants and animals
Function-binds with calcium and prevents calcium from being used in the body
Foods-soy, nuts, beans, spinach, swiss chard, beets, collard greens, okra, blueberries, grapes, raspberries
Definition-chemicals naturally produced by plants that are not of conventional nutritional value
Function-functions vary but they are usually antioxidants, anti-inflammatory and promote liver health
Foods-plants, especially ones rich in color
Protein - Click Here for More Information
Definition-a biological molecule made of chemically linked amino acids
Function-maintains the structure of the body and excess can be used as an energy source
Foods-all foods have some protein, with meat, whole prey, insects, crustaceans, mollusks and mice being especially high
Definition- an abundant chemical element that essential for life
Function-enables cell function and builds bones, but is easily consumed in excess in a cricket’s diet. Excess consumption impairs calcium absorption and can cause muscle disorders.
Foods-asparagus, beans, soy, seeds, cricket, mealworms, mushroom
Definition-A vital organic compound that an organism cannot synthesize on its own. They can be divided into fat soluble and water soluble.
Function-each vitamin has its own function in the body
Definition-a group of related fat-soluble nutrients (carotenoids and retinoids) that are essential for the body.
Function- Carotenoids come from plants and cannot be overdosed, so they are the safest form of vitamin A, however savannah monitors can't convert carotenoids to retinoids. Vitamin A is needed for immune responses, night vision and many other functions in
Foods-whole prey items, egg yolk, turkey liver
Definition-a fat soluble vitamin derived from UVB light or dietary sources
Function- needed to absorb calcium and other minerals from food
Foods-It is currently controversial if savannah monitors need UVB lighting. It is recommended to provide a source of UVB in order to err on the side of caution.
Definition-a fat soluble vitamin that acts as a powerful antioxidant
Function-protects against free radical damage, ageing and heart disease. It is especially crucial in a high fat diet. Most foods high in vitamin E are also high in fat, so a balance is difficult to achieve.
Foods-sunflower seeds, shrimp, greens. almonds, broccoli
Science Behind the Pyramid:
The proportions of the pyramid are based on macronutrient balancing. According to the Merck Veterinary Manual, omnivorous reptiles need a diet of 20-25% protein, 3-6% fat and 20-35% fiber on a dry matter basis. According to this manual carnivorous reptiles need 30-50% protein. To achieve these macronutrient ratios the pyramid recommends how often to feed a portion of insects, whole prey and lean meat. There is a total of 8 portions of these food groups fed each week.
5 insect portions/8 total portions=62.5% insects
1 lean meat portions/8 total portions=12.5 % lean meat
2 whole prey portions/8 total portions=25.0% whole prey
The most important macronutrient is protein. The diet aims to achieve a >30% dry matter protein content. Insects, lean meat and whole prey are typically , 50%, 70% and 60% protein, respectively. Multiplying the % of protein by the proportion of portions gives us:
.624x50% + .125x70% + .250x60% = 55.0% protein
Therefor this food pyramid provides an adequate amount of protein. Using this same method fat and fiber can also be calculated. Insects, lean meat and whole prey are typically 18%, 10% and 20% fat, respectively. They are typically 10%, 2% and 5% fiber, respectively.
.624x18% + .125x10% + .250x20% = 17.5% fat (goal 3%-6% omnivores, much greater for carnivores)
.624x10% + .125x2% + .250x5% = 7.7% fiber (goal 20%-35%, much lower for carnivores)