That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

We’ve long known that many reptiles need Ultra Violet B (UVB) light exposure in order to manufacture Vitamin D3. Vitamin D3, which is essential for proper calcium uptake, is also present in many foods, and some reptiles can utilize it in this form.  However, there are some gray areas.  It seems that reptiles long considered incapable of using dietary D3 (and which therefore need UVB light exposure), can sometimes obtain D3 from their diet (please see chameleon and day gecko articles linked below).  Generalizations can be misleading – for example, the study summarized below shows that two anole species sharing the same habitat obtain D3 in very different ways.

 

Anole Study – Vitamin D3 and Basking Behavior

A study recently published in the Journal of Herpetology [47 (4) 524-29, 2013] examined whether the level of Vitamin D3 in the diet would affect the basking behavior of two anole species.  Earlier research had shown that Panther Chameleons do alter their basking behavior in response to blood levels of Vitamin D3; please see the article linked below for details.

 

Wild and captive Brown Anoles, Anolis sagrei and Stripefoot Anoles, A. lineatopus, living in Jamaica were used as study subjects.  When the D3 content of the diet was increased, Brown Anoles decreased the amount of time they spent basking in UVB light.  This remained constant over a 6 week period.  This indicated that they were obtaining enough D3 from their diet. When the dietary D3 was decreased, the Brown Anoles increased their exposure to UVB, so as to be able to manufacture D3 in the skin.

 

Stripefoot Anoles, on the other hand, did not decrease their basking time when fed high levels on D3, and they did not increase basking behavior when fed diets low in D3.

 

The researchers therefore concluded that Brown Anoles are able to use dietary D3, while Stripefoot Anoles cannot.  Stripefoot Anoles seem to rely upon the Vitamin D3 that is produced in their skin when it is exposed to UVB light.

 

Studies such as this show us that we must carefully research the needs of each species under our care.  Even if they are closely related, and share similar habitats, diets, and lifestyles, captive conditions that work for one could spell doom for another.

 

My Experience: Day Geckos Without UVB Did Well

I’ve made some related observations on Madagascar and Standing’s Day Geckos.  UVB exposure has generally been considered critical to their welfare in captivity.  Yet a colony of both, living at semi-liberty in a large zoo aviary, seems to be doing very well without access to UVB light.  Please see the article linked below for further details.

 

Providing UVB to Lizards and other Reptiles

Natural sunlight is the best source of UVB, but it is important to bear in mind that overheating can occur quickly, and that UVB does not penetrate glass or plastic.  Reptiles housed or placed outdoors must also be protected from rats, raccoons, dogs, cats, crows and other predators.  Where conditions permit, screen cages offer a great means of providing natural UVB to your pets.

 

UVB Bulbs

In recent tests, the Zoo Med 5.0 and 10.0 Bulbs were found superior to several other models.  Mercury vapor and compact florescent bulbs generally emit higher levels of UVB than traditional florescent bulbs, and they broadcast it over greater distances.  Mercury vapor bulbs also produce heat, and so may eliminate the need for an additional heat source.

 

 

 

Further Reading

Chameleon Basking Behavior Influenced by UVB Needs

My Notes: Day Geckos Thrive Without a UVB Source

Using Compact UVB Bulbs

 Using Screen Cages

 

 

Although many salamanders will eagerly gobble-up crickets and mealworms, a diet restricted to these food items usually leads to nutritional disorders and reduced life-spans.  This holds true even if supplements are used.  A varied diet is essential if you are to have success in keeping salamanders long-term (my 32 year-old Red Salamander, 25 year-old Fire Salamanders and numerous others can attest to this!).  Following are some useful tips for those seeking to vary the diets of their terrestrial salamanders.  While most newts and aquatic species (Axolotls, Amphiumas) accept dry foods, they too will benefit from invertebrate meals.  Please post below for detailed information on individual salamander species.  As there is an endless supply of useful live foods for pet salamanders, please also post your ideas and observations.

Earthworms, Red Wigglers, Nightcrawlers (Lumbricus terrestris and relatives)

If you need to rely upon a single food item as a dietary staple for your salamanders, it should be earthworms, not crickets. I cannot recall a single salamander species that does not fare well on an earthworm-rich diet.  Earthworms and their relatives reproduce rapidly when kept properly (please see article below) and can be stored for weeks under refrigeration.  Their nutritional profile can be improved by a diet of leaf litter, corn meal, fish flakes and calcium powder. Read More »

Today I’d like to offer some gift suggestions for the herp enthusiasts on your holiday shopping list.  I’ve made my choices with younger folks and novices in mind, but all are useful to long-term keepers as well (indeed, we dinosaurs often stick to “ancient” products and ignore new innovations!).  I believe that the products I’ve highlighted are important because they will start hobbyists thinking about concepts that are often overlooked early-on, such as water quality, temperature gradients, UVA, dietary variety and reading materials.  Some of my recommendations will need to be fine-tuned to fit individual species.  Please post below and see the linked articles for further information, and be sure to add your own thoughts and gift-giving suggestions.

 

Hygrometers and Thermometers

When I first began using sophisticated testing equipment in zoos, I was surprised to discover how widely humidity and temperature levels can vary within even small exhibits.   Back then, hobbyists were pretty much limited to aquarium thermometers and the like.  Today, pet owners have a wide assortment of professional-quality hygrometers and thermometers from which to choose. Read More »

Swollen, inflamed eyes are commonly seen in a wide variety of captive turtles.  Strangely, the hardy Red Eared Slider seems especially prone to this annoying and potentially life-threatening condition (as we’ll see, popular feeding practices may partially explain this).  From childhood through my career as a herpetologist, standard wisdom has blamed the condition on a Vitamin A deficiency. Today we also know that poor water quality is responsible for many, if not most, of the eye problems seen in Sliders, Cooters, Painted Turtles and similar species.  In this article we will look at the symptoms, causes, prevention and treatment of various turtle eye maladies.

Symptoms

Most eye problems first manifest as a slight but noticeable puffiness of the eyelids.  Vitamin A deficiencies and fungal/bacterial infections can cause tissue within and around the eyes to degrade.  As a result, epithelial cell “debris” collects along the eye rims and under the lids. Pressure and irritation causes the lids and tear ducts to swell. Read More »

In the course of my work, I am often contacted by turtle owners whose pets cease feeding and become unusually restless.  The behavior appears suddenly, sometimes after many uneventful years – a Common Musk Turtle did so after 22 years in my collection – and seems to have no external cause.  A normally placid turtle may begin frantically paddling or wandering about, trying to climb the sides of the terrarium and escape.  Food, once the focus of the creature’s existence, is ignored.

It surprises some folks to learn that turtle and tortoise eggs may develop even if the female has never mated, and that mated animals may retain sperm and produce fertile eggs years later.  Unfortunately, gravid (egg-bearing) turtles can be very choosy when it comes to nesting sites…a ½ acre exhibit failed to satisfy some I’ve cared for at the Bronx Zoo!  If the eggs are not deposited, blockages due to over-calcification and life-threatening infections invariably result.  Fortunately, there are ways to “convince” your pet to lay her eggs; failing this, several effective veterinary options are available.

What To Do

If your female turtle or tortoise suddenly stops feeding and begins to act as described above, first check that something has not gone wrong in the environment.  Overheating, Lysol poured into the tank by a mischievous child (actual story), or cage-mate aggression can all cause similar behaviors.

If you suspect eggs, your best option would be to have radiographs done by a veterinarian (please post below if you need help in locating an experienced vet).  Your vet can determine how many eggs are present, approximately how far along they are in their development, and if problems related to unusual size or over-calcification can be expected.  Also, other health issues that may cause similar symptoms can be investigated. Read More »