Blue Tongue Skink Food Pyramid
The pyramid is a guide to feed your blue tongue skink. 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 blue tongue skink diets. This pyramid is also based off of what experienced blue tongue skink breeders have found to work for their animals.
The blue tongue skink food pyramid is designed to be a user-friendly guide. The foods on the bottom are the most important, however all the food groups are necessary for a healthy blue tongue skink. The key on the right side describes how many times to feed this food group per a week. When the pyramid level is broken in half, you can choose either food group. The larger the section, the more important it is.
This guide is made to combat the incomplete knowledge of blue tongue skink nutrition. Many new owners are confused about what to feed their pets while experienced owners are looking for the best diet possible. Currently, many breeders recommend dog food supplemented with fresh vegetables. This is a simple and successful way to keep blue tongue skinks due to the complete vitamin and mineral profile, however it is not very natural or exciting for a blue tongue skink and may lead to obesity if not fed correctly. With this guide you should be able to make an informed decision on a dog food/vegetable diet or be able to feed a healthy home-made diet.
There is no such thing as a complete guide to blue tongue skink nutrition because there is no realistic way for the in-home keeper to formulate a total diet. It is conventional wisdom that variety is key to combat an incomplete diet, but that isn’t always the case. For example, almost all the foods a blue tongue skink is fed will be deficient in calcium and iodine. This is simply a product of commercial agriculture raising plants and insects so that they grow as cost effectively as possible.
This guide will get you as close as possible to a complete diet without expensive scientific testing. 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:
Greens should be feed every meal due to the fact that they are a great source of nutrition. The amount of vegetative matter that blue tongue skinks eat in the wild can vary greatly between seasons and individuals (Fenner et al. 2007 and Shea 2006), but it is important that they are offered frequently as it really is impossible for these animals to eat too much vegetative matter. 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
Insects are the major protein source for blue tongue skink nutrition. This is backed up by Shea (2006), who observed arthropods in 73% of blue tongue skink stomach samples, while vertebrates were only observed in 20% of samples. Tenner et al. (2007) also found that arthropods are the majority of the diet of the pygmy blue tongue skink.
Most commercially raised insects are deficient in several nutrients, including calcium, thiamin (vitamin B1), vitamin A and vitamin E. Since blue tongue skinks get a large amount of their nutrients from the plant portion of their diet it is less essential to dust or gut load insects than with a reptile that exclusively eats insects. However, it is a good idea to gut load rather than dust. This is because gut loading is much more effective. Gut loading for blue tongue skinks should focus on calcium, as they can get most of the other nutrients that insects lack from the plant portion of their diet. The insects fed should also be low in fat content.
Ideal insects include crickets, roaches, hornworms, earthworms and soldier fly larva (reptiworms).
Insects that should be fed more sparingly due to their fat content include mealworms , super worms and waxworms.
Check out the nutritional analysis of some common feeder insects.
Meat is another source of protein for blue tongue skinks, but is less common for them to consume in the wild, according to stomach content analysis by Shea (2006). If fed enough insect protein it is not an essential part of the diet, but premium canned cat food can be a good way to ensure vitamin and
mineral supplementation while providing a protein source. One should take care to only feed lean meats, as the high fat content of meat can be hard on the liver of a blue tongue skink.
Good lean meats include, premium canned cat food, cooked ground turkey, cooked chicken
Meats to feed occasionally include pinky mice, egg whites, cooked lean ground beef
This is the part of a blue tongue skink’s diet that will bring in a diversity of nutrients and a ton of beta-carotene. 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, 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.
Fruit is a less essential part of the blue tongue skink diet. Not only do they eat less fruit than vegetables in the wild, almost all fruit you can buy in the store is heavily domesticated and has little relation to the nutritional content of its wild relatives. Fruit should be used as a flavor enhancer more than a nutritional component of the food, but is great to feed in moderation.
Some healthy fruits include berries, cantelope, dates, figs, guava, kiwi, mango, oranges, papaya and pineapple.
Liberally sprinkle a vitamin supplement on the skink's food. A vitamin and mineral supplement is essential when feeding a home made diet to ensure no nutrients are missing, however there is quite a variety of supplements on the market. When looking for a supplement to a healthy blue tongue skink diet, as outlined here, there are a few key nutrients one should consider. Most greens, insects, fruits and vegetables are low in magnesium, iron and iodine. Make sure your supplement provides these nutrients as well as ample amounts of B vitamins. Often iodide is provided using kelp as an ingredient. Additionally, vitamin A should be provided in a retinol form because it is not know if these animals can synthesize vitamin A retinol from beta-carotene.
Gut load all insects with calcium and liberally dust on other foods. A calcium supplement should be purchased separately from a vitamin and mineral supplement. This is because calcium needs to be supplemented in a much higher level than any other mineral. Most foods for blue tongue skinks are deficient in calcium and calcium is required more than any other mineral in reptiles. Also be sure that you have proper UVB lighting. Without UVB, blue tongue skinks cannot have enough vitamin D in their system to process the calcium they are eating. Supplementing calcium is useless without UVB lights as dietary vitamin D is not absorbed by most reptiles.
Fenner, Aaron L., Michael C. Bull and Mark Hutchinson. Omnivorous diet of the endangered Pygmy Bluetongue Lizard, Tiliqua adelaidensis. Amphibia-Reptilia. 28(4):560-565 (2007).
Shea, Glenn, M. Diet of two species of blue tongue skink, Tiliqua multifasciata and Tiliqua occipitalis (Squamata Scincidae). Australian Zoologist. 33:359-368 (2006).
These dietary guidelines are designed for an average, healthy, blue tongue skink. 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 blue tongue skinks. If your blue tongue skink is sick please check out our diagnostics page.
Similar to hibernation, many reptiles go through a dormant cycle in the wintertime. Assuming your husbandry is correct, this is perfectly normal. Their appetites will decrease so they many not need to be fed as much or as often. The most important thing is to ensure that they remain hydrated during this time. Blue tongue skinks get most of their water from their food and may not drink for a bowl. Misting the glass wall for them to drink up “dew” when they are active is one common tactic to ensure hydration.
Obesity is rare in blue tongue skinks when compared to other captive reptiles, but does still occur. If you have an obese animal it is recommended that you consult a veterinarian to examine for underlying issues. Obesity is deadly. It can cause or be caused by liver failure and many other issues. Once examined by a veterinarian, reduce the amount of meat in the diet and feed only lean insects as a protein source. Supplementing with a very small amount of omega 3 fish oil is also wise to prevent liver disease in obese animals.
Young blue tongue skinks are growing fast and need more protein and calcium than older blue tongue skinks. It is wise to increase the amount of insects offered to them, but not meats. A young blue tongue skink in the wild is unlikely to eat anything but insects as a protein source. 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, water is the most important nutrient for blue tongue skinks. Make sure your animal does not become dehydrated. Also remember that eating any food is better than eating no food. Even if all your blue tongue skink will eat is cheap canned dog food 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 blue tongue skink’s diet. Calcium is a particularly important nutrient that many beginner keepers do not offer enough of. It is imperative to supplement your blue tongue skink with calcium and provide proper UVB lighting.
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, prickly pear leafs, collard greens, oranges, soldier fly larva, mustard greens, bell peppers
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 blue tongue skinks and inhibits zinc uptake, so copper intake 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-waxworms, superworms, mealworms, nuts, seeds, ground beef, egg yolk
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 should be avoided in excess in order to maintain thyroid health of blue tongue skinks. They are less harmful when proper iodine supplementation is provided.
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 to form kidney stones and prevent 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 insects and meats being especially high as well as a decent amount of protein in nuts and seeds
Definition- an abundant chemical element that essential for life
Function-enables cell function and builds bones, but is easily consumed in excess in a blue tongue skink’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 it is not known if blue tongue skink’s can convert carotenoids to retinoids. Vitamin A is needed for immune responses, night vision and many other functions in
Foods-egg yolk, turkey liver, pinky mice
Definition-a fat soluble vitamin derived from UVB light or dietary sources
Function- needed to absorb calcium and other minerals from food
Foods-UVB lighting should be provided for blue tongue skinks so that they can synthesize vitamin D, numerous studies have indicated that dietary supplementation is not an effective source of vitamin D in diurnal reptiles.
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. To achieve these macronutrient ratios the pyramid recommends how often to feed a portion of insects, greens, fruits or vegetables. There is a total of 18 portions of these food groups fed each week.
5 greens portions/13 total portions=38.5% greens
3 vegetable portions/13 total portions=23.1% vegetables
1 fruit portion/13 total portions=7.7% fruit
3 insect portions/13 total portions=23.1% insects
1 meat portions/13 total portions=7.7 % meat
The most important macronutrient is protein. The diet aims to achieve a about 20-25% dry matter protein content. Greens, vegetables, fruit, insects and meat are typically 20%, 10%, 5%, 50% and 60% protein, respectively. Multiplying the % of protein by the proportion of portions gives us:
.385x20% + .231x10% + .077x5% + .231x50% + .077x60%= 26.6% protein
Therefor this food pyramid provides an adequate amount of protein. Using this same method fat and fiber can also be calculated. Greens, vegetables, fruit, insects and meat are typically 2%, 2%, 2%, 18% and 20% fat, respectively. They are typically 25%, 25%,15%, 10% and 2% fiber, respectively.
.385x2% + .231x2% + .077x2% + .231x18% + .077x20%= 7.1% fat (goal 3%-6%)
.385x25% + .231x25% + .077x15% + .231x10% + .077x2%= 19.1% fiber (goal 20%-35%)