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

The technology behind amphibian and reptile lighting has come a long way since I began working at the Bronx Zoo, when “black lights” and the sun were our only UVB (Ultra Violet B radiation) options.  Today I’ll review an important herp husbandry innovation, the compact UVB fluorescent bulb (note: bulbs are referred to as “lamps” in technical papers).  My experiences have been positive, but some reptile-keepers have raised concerns, so I’ll address them as well. Please be sure to post your experiences and ideas below, as we still have much to learn about this important topic.

Uploaded to Wikipedia Commons by Dave Pape

Reptiles, UVB and UVA: a Quick Primer

Most heliothermic (basking) lizards, turtles, and crocodilians need exposure to UVB light rays with a wavelength of 290-315 nanometers in order to synthesize Vitamin D3 in their skin.  Vitamin D3 allows these animals to utilize dietary calcium.  Without D3, dietary calcium is not metabolized and metabolic bone disease sets in.  Snakes, highly-aquatic turtles, nocturnal lizards, most amphibians, and certain others can make use of dietary Vitamin D, but most basking species rely on the skin-synthesized form. Read More »

Although I have kept reptiles and amphibians since childhood, and worked in zoos for most of my adult life, I remain amazed by the array of herp-care innovations that are available to us today.  True, not all are necessary (and some are downright ridiculous!), but many are indispensable to serious hobbyists and zookeepers alike.   Advances in reptile lighting technology, for example, help private keepers to breed animals that, not so long ago, failed to thrive even in large zoos.

I’m particularly fond of combination hoods and fixtures, especially when I recall the rat’s nest of tangled wires and lamps that topped every zoo exhibit and holding cage years ago…thinking back to my early years at the Bronx Zoo, I cannot imagine how we avoided fires and electrocution!  Combo hoods have space for several different types of bulb, allowing us to keep UVA, UVB, heat and night (red/black) bulbs in one place. In addition to the convenience factor, the movable sockets and integrated timers included in some models increase our ability to establish thermal gradients, natural day/night cycles and “dawn/dusk” periods.  Today I’ll review a few reasonably-priced units offered by two well-known leaders in the field. Read More »

Please see Part I of this article for a description of UVA light, information about its importance to reptiles and amphibians and its role in their captive husbandry.

Light and Heat

In addition to promoting natural behavior and improving the appetites of many captive reptiles and amphibians, ( Part I), the light emitted by UVA bulbs will also accentuate your pets’ natural colors.

The models listed below are incandescent, and therefore provide heat and encourage basking.  When placed in close proximity to florescent UVB bulbs (which emit little heat), UVA bulbs can help assure that your pets receive the full spectrum of essential light rays.

Light Cycle

The length of the UVA light cycle provided is critical, especially for those creatures that are native to areas subjected to seasonal changes in sunlight intensity and duration.  Ideally, you should study the natural habits and ranges of the animals in your collection, and endeavor to provide them with an appropriate light cycle.

Suggested UVA-Emitting Bulbs (Lamps)

Zoo Med manufactures a number of useful UVA bulbs. Repti-Halogen Bulbs are available in 50-150 watt sizes.  Repti-Basking Spotlights offer a narrow, tight beam, and range in size from 25-150 watts.

Zoo Med Turtle Tuff Halogen Bulbs  are water-resistant, and so can stand up to the splashing that is so common around aquatic turtle basking areas without breaking.  They have an average life of 2,500 hours.

Other high quality UVA bulbs include the Hagen Sun Glo Daylight Halogen and R-Zilla’s Spot Day White Bulbs and Incandescent Day White Bulbs.

Last time I reported on the Staten Islands Zoo’s use of the Zoo Med 10.0 High Output UVB Lamp (Please see Part I of this article). Today I’d like to provide some specifics concerning tests carried out there.

Test Results
The UVB output readings recorded at the Staten Island Zoo are as follows (note: measurements are expressed in microwatts per centimeter squared, the standard for measuring UVB output):

Zoo Med Reptisun 10.0 High Output UVB Lamp

Zoo Med Reptisun 5.0 UVB Lamp

As you can see, the basking site’s distance from the lamp has a major impact upon UVB exposure, as does the screen cover’s deflection of light rays. With a bit of creativity, basking spots within 6 inches of the lamp can be arranged in most situations, and this is certainly the way to go for many species. Where safe to do so, dispensing with the screen cover is another option.

Using a Separate Basking Enclosure
If a 6-inch basking site or uncovered top are not feasible in your pet’s terrarium, consider the possibility of utilizing a separate basking enclosure for a few hours each day. When keeping young radiated and star tortoises in high-topped zoo exhibits, where adequate UVB exposure was not possible, I rotated the animals into a low, uncovered container every day or so, and achieved excellent results.

If you go this route, be sure to keep your pet’s individual needs and temperament in mind. For example, a simple, open container that might suit a Greek tortoise would likely cause a good deal stress to a flat-rock lizard. High strung or secretive animals must be made to feel secure in the basking enclosure, or you may do more harm than good.

Reflectors and UVB Output
The group UV Guide UK has found that simply mounting the lamp within a metal reflector nearly doubles the UVB light that is available to basking animals. In addition to focusing all of the lamp’s light into the terrarium, I imagine that the reflector also helps by deflecting back some of the light that has bounced off screen tops or other structures.

An informative article on the role of UVB and basking behavior in Vitamin D synthesis is posted at:
http://www.uvguide.co.uk/vitdpathway.htm

We have learned a great deal about the Ultraviolet B (UVB) light requirements of reptiles in recent years. However, the actual process of providing our pets with UVB of the correct wavelength (290-315 nanometers) remains fraught with confusion.

While helping to set up the new reptile house at New York City’s Staten Island Zoo (former stomping grounds of famed herpetologist Carl Kauffeld), I spoke with several pioneering researchers in the field of reptile UVB requirements, and have since monitored the building’s exhibits.

Recent Tests at the Staten Island Zoo
Recently, the zoo’s reptile keepers ran some tests in order to measure the UVB output of fluorescent lamps (bulbs) used in some of the exhibits and holding cages. While mercury vapor lamps often provide more UVB over a greater range, they are sometimes unsuitable for small cages, or for use with certain species. This study focused on fluorescent lamps, which are commonly used by pet keepers as well.

Using a UVB meter, the staff found that the Zoo Med Reptisun 10.0 High Output UVB Lamp provided high levels of UVB, with the Zoo Med Reptisun 5.0 UVB Lamp being valuable in some situations as well.

Earlier Research on Zoo Med Lamps
I did a bit of research, and learned that a group known as UV Guide UK (please see below) had earlier cited research showing that the Reptisun 5.0 (the 10.0 was not tested) scored highest of all fluorescent tubes in what is known as the D3 Index (the projected ability of lamp to foster Vitamin D synthesis). UV Guide UK also found that the Zoo Med 10.0 and 5.0 lamps lead other fluorescents in UVB output.

Zoo Med Lamps on Lizard Exhibits
The Staten Island Zoo currently uses the Zoo Med 10.0 High Output UVB Lamp with a number of lizards, including such sensitive species as the crevice spiny swift (Sceloporus poinsetti) and the Texas horned lizard (Phrynosoma cornutum).

Check out the specifics of the UVB output readings recorded at the zoo, and take a look at a simple method of increasing the output of any UVB lamp at part II of this article.

You can read more about the work of UV Guide UK, including the tests mentioned, at the following site (Note: the original tests were in 2005…the Zoo Med Lamps have been upgraded in the interim).