There are many different species of tortoise in the world. Some are fruit-eating species and some are recommended to seriously limit their fruit intake.
Mediterranean, grazing, and desert tortoises do not have digestive systems designed to digest high sugar foods, therefore it is not recommended that fruit is a major area of their diet.
What species eat fruit?
The Red- and Yellow-Footed tortoise, and the Elongated tortoise species are all known to have a decent percentage of fruit in their natural diet. These species are often found in forest regions where fruit would naturally be found.
Species such as Hermann’s, Horsfield’s, African Sulcata, Leopard, and Indian Star tortoises are naturally found in drier and arid climates. There is not much fresh produce found here and so these species have evolved to survive primarily on leaves and stems. It is not recommended that you feed these species fruits, as it could lead them to developing health issues.
Calcium and phosphorus are 2 minerals that are absolutely vital for the health of your tortoise. Calcium is required to grow and develop a healthy skeleton and shell. It helps to regulate their heartbeats, blood health, blood clotting, and nerve transmission.
It is also used to balance the acid-base levels in their bodies, muscular growth and contraction, the absorption of zinc, and the activation of lots of enzymes.
A calcium deficiency can lead to your tortoise developing metabolic bone diseases, weak bones, and a deformed shell. If your tortoise is laying eggs, calcium is even more vital. If there is not enough calcium in their diet their egg production will decline.
Phosphorus is another mineral that it is important for your tortoise to consume. It helps chemical reactions to occur within the body such as the breaking down and usage of fats, proteins, and carbohydrates.
It is also used to pass on hereditary traits, the transfer of nerve impulses, and with kidney function.
Watermelon is not particularly high in this mineral, and nor is much of the other foods they consume. This means that you must supplement calcium in their diets. Good, tortoise-friendly sources of calcium include cuttlefish bones, tortoise block, and powdered calcium supplements.
It is important to balance the levels of calcium and phosphorus in your tortoise’s diet. High phosphorus levels in the body cause a decline in calcium absorption.
This is because the phosphorus will bind with the calcium to form calcium phosphates. This prevents the calcium from being absorbed.
The recommended ratio in their diet is 2:1 of calcium to phosphorus. This is easy to manage by feeding your tortoise primarily foods that have an inverse calcium to phosphate ratio. With the exception of papaya, this is the case for most fruits.
Your tortoise will not be able to absorb calcium properly without adequate levels of Vitamin D. They can get this by sitting in the sunlight for a few hours. If this is not something you have access to, such as in the winter months, we advise feeding your tortoise Vitamin D supplements.
There are a number of acids contained within watermelon, alongside the high sugar content of the fruit. Both of these can pose health risks to your tortoise if consumed in excess. This can cause a shift in the pH value of the digestive tract. This can then cause the beneficial bacteria microbiome in your tortoise’s gut to die off.
The bacteria in question are vital to your tortoise’s overall health. They assist with digestion and extracting nutrition from foods such as grass.
The dead bacteria release a large number of toxins. These have the capacity to cross through the wall of your tortoise’s gut and enter the bloodstream. If this happens, your tortoise will go into a state of toxic shock syndrome which can eventually be fatal.
Benefits of Feeding Tortoises Watermelon
Watermelon is a fruit with an incredibly high water content, making it a great source of hydration for your tortoise. This is particularly true during the warmer months where there is a higher risk of dehydration.
There are sugars and minerals found in watermelon which your tortoise will love. These can be very healthy if they make up a small portion of your tortoise’s diet.
Risks of Feeding Tortoises Watermelon
As the water content of watermelon is so high, it can cause digestive problems in your tortoise if consumed in excess. The most likely issue to arise will be diarrhea. While not hugely dangerous, this will be unpleasant for both you and your tortoise. It is easily avoided by feeding them in moderation.
How to Feed Tortoises Watermelon
Fruit, vegetables, and greens should only make up around 10% of your tortoise’s diet. Too much can lead to adverse health effects, so take care to monitor the quantity of fresh produce you give your tortoise. We advise feeding your tortoise fresh fruits and vegetables once a week.
To feed your tortoise watermelon you should first wash it well. Cut it into small pieces that will easily fit inside their mouth. It is a good idea to combine the watermelon with other produce in their food bowl. Good options to combine with include papaya, banana, apples, pineapples, and mango.
Leave these fruits in the food bowl for 24 hours to allow your tortoise time to pick at them. After this time has passed we recommend taking the fresh foods out to avoid them rotting.
You can leave the rind on the watermelon when you feed it to your tortoise. They may choose not to eat it, but if they do it is perfectly safe for them to consume. This is why we advise washing your watermelon before cutting it up.
The tough rind of a watermelon can actually be beneficial to your tortoise. It will give them something to gnaw on, keeping their teeth and jaws healthy. It can also help to wear down their beak a little, preventing it from becoming overgrown.