Reptile UVB Bulbs: Insights on the Best from Zoo-Based Herpetologists

Ploughshare Tortoise

Uploaded to Wikipedia Commons by Hans Hillewaert

I recently attended the NY Turtle and Tortoise Society’s (always fabulous!) annual conference on turtle and tortoise care and conservation, and had a chance to catch up with friends and former zoo co-workers. I learned that certain UVB bulbs manufactured by Zoo Med have been used to achieve significant improvements in the health and (possibly) reproductive output of captive tortoises. Over the course of my career as a zookeeper and herpetologist, I’ve tried to convince my zoo colleagues to consider the promising reptile care products available in the pet trade. I was not always (or, perhaps, not often!) successful, but zookeepers were doing the same elsewhere, and progress was made. Today, many products favored by well-informed private herp keepers are also in use in the world’s leading zoological parks. In this article I’ll relate some interesting findings concerning the role of UVB bulbs and sunlight in the care of Radiated Tortoise (Astrochelys radiata) and other h


The conference I attended is a day-long event sponsored annually by my favorite turtle care and conservation organization, the New York Turtle and Tortoise Society; please check this website to read about their fine work…and to see photos from my recent presentation there. As in so many years past, legendary herpetologist Peter Pritchard graciously traveled to NYC to anchor the event.


t262180gVitamin D3 Deficiency

Through presentations and conversations, I learned that Zoo Med T5 UVB and Mercury Vapor Bulbs have proven useful in the care of Radiated Tortoises (Astrochelys radiata) and other heliothermic (basking) reptiles. When blood tests revealed low levels of circulating D3, the UVB bulbs in a large tortoise exhibit were replaced with those mentioned above. Florescent bulbs (the Zoo Med T5), which do not emit significant heat, were paired with mercury vapor bulbs, which produce both heat and UVB. This technique, useful for pets as well, assures maximum UVB exposure by drawing animals to a heat source. When possible, the Radiated Tortoises were also exposed to several hours of natural, unfiltered sunlight.


Research is ongoing, but the tortoises’ D3 levels are now at normal levels, and several previously-infertile females have produced viable eggs. I’m interested to see if the effects of the bulbs and the sunlight can be distinguished (nothing tops natural sunlight, of course).


Several Ringtail Lemurs that share the tortoise exhibit also became very fond of basking under the new lights…maybe some bright young researcher will be asked to look into sunscreen for non-human primates!


T5 and Mercury Vapor Bulbs

Zoo Med’s T5 Florescent Bulbs are available in two strengths and several lengths, and must be paired with T5 fixtures or hoods. They are rated to emit UVB over a distance of 22-24 inches, at levels that double the output of Zoo Med’s traditional bulbs (anecdotal evidence may indicate a greater range, but further work is needed). In situations where traditional bulbs will be adequate, Zoo Med’s standard 5.0 and 10.0 are good choices. One study found that they out-performed similar models (please see the article linked below). Both models provide UVA as well.


Zoo Med’s Powersun and Exo-Terra’s Solar Glow Mercury Vapor Bulbs broadcast UVB to a distance of 36 and 22 inches respectively, and also produce UVA and heat. In many home situations, they can double as a basking light and UVB source, eliminating the need for other bulbs.


Common Flat Rock Lizard

Uploaded to Wikipedia Commons by Sputniktilt

Which Reptile UVB Bulb is Best?

Choosing a UVB source had once been easy – unfiltered sunlight was the only source (and it remains unmatched). By the time I began working at the Bronx Zoo, our choices had expanded to include “black-light bulbs” and Vita-Lights. Today a bit of forethought and research is needed before one goes bulb-shopping. Please post any questions or thoughts below.




Further Reading

Zoo Med’s Standard UVB Bulbs: Test results

Chameleon Basking Time Affected by D3 Levels



Your First Pet Snake: A Checklist of Things to Consider

Honduran Milksnake

Uploaded to Wikipedia Commons by Haplochromis

Snakes are almost mainstream pets these days, but I still see evidence that many people jump into snake ownership without fully considering all that is involved. In the course of my work as a reptile keeper at the Bronx Zoo, and now as a consultant for ThatFishPlace-ThatPetPlace, I’ve come-up with a list of important points that, if considered beforehand, will greatly improve life for both snake and snake owner. As always, please be sure to post any questions, or additional factors that you have found to be important, below. Please also see the articles linked below for my “best pet snake” recommendations.


Captive-Bred vs. Wild Caught: This is much easier to check today than in years past. Snakes born in captivity do not drain wild populations, are less likely to harbor parasites or diseases, and are generally easier to handle than are their wild relatives.


Handle-ability and other Pet Qualities: Snakes will not seek human companionship…as legendary snake expert Bill Haast put it “You can have a snake for 30 years, but leave the cage open, and it’s gone – and it won’t come back unless you have a mouse in your mouth”! Snakes definitely adjust to captivity, and some species accept handling better than others, but they should not be expected to be “friendly”.


The “It Doesn’t Do Anything” Factor: Ideally, the new snake owner will be interested in her or his pet for its own sake. But we also wish to see how it lives, what it does, and so on. Most snakes, especially well-fed pets, are about as active as the infamous “pet rock”!   If you want motion, consider a small species that actively forages for its food, and keep it in a large, naturalistic terrarium. A pair of Garter Snakes in a well-planted 55 gallon tank will provide you with infinitely more to observe than will a Burmese Python in a large zoo exhibit.


Western Garter Snake

Uploaded to Wikipedia Commons by Steve Jurvetson

Costs of Owning A Snake: Your pet’s initial purchase price is but one part of the cost of snake ownership, which also includes electricity use, veterinary care (as expensive as dog/cat care), food, enclosure, and so on. With some planning, you can easily limit costs. A Garter Snake needs only a 20 gallon aquarium with (in winter) a low-wattage basking bulb, and a diet of minnows and earthworms…much less expensive than a 6 foot-long Boa Constrictor kept in a custom-made cage heated year-round with powerful bulbs and feeding upon pre-killed rats.


Veterinary Reptile Care: Reptile-experienced veterinarians are difficult to find in many regions. Trust me – it is a grave mistake to embark on snake ownership before locating a veterinarian, or to imagine that even the hardiest of species will not require medical care.  Please post below if you need assistance in finding a reptile-experienced veterinarian in your area.


Safety: All snakes, even the shyest and smallest, will bite when threatened, and they may react to scents, vibrations and other cues that we cannot perceive. Even minor bites should be treated by a doctor, to avoid infection, tetanus and other complications. Large constrictors have killed their owners and venomous species, which should never be kept, are regularly offered for sale. While easily managed with proper hygiene, Salmonella, which is generally carried by all reptiles, presents grave risks to certain people. Please see the article linked below and contact your doctor for advice.


Space: While snakes can make due with less space than many other creatures, you’ll see more of interest if your pet has ample room to move about. Be sure to research (feel free to post below) your snake’s ultimate size and typical growth rate. And please remember – zoos will not accept unwanted pets and, even if native, they cannot be released into the wild!


African House Snake

Uploaded to Wikipedia Commons by Purplegerbil

Time Commitment: Depending upon the species and size of your pet, its care can range from a short, more-or-less weekly job (Kenyan Sand Boa) to a major, near-daily chore (Indigo Snake). Long term care should also be considered – Corn Snakes and other popular pets regularly live into their teens and twenties, while Ball Pythons may exceed 30, 40 or even 50 years of age!


Diet: Not everyone (or everyone’s significant others!) can accept a pet that consumes dead rodents. Unfortunately, Smooth Green Snakes and other insect-eaters usually refuse crickets and other readily-available foods (canned silkworms may be a useful alternative). The fish-eating Water Garter and Ribbon Snakes are a good option for many folks.

Considering a snake purchase is an important decision. If you need more time to consider the aspects of owning a snake, print out the following abbreviated check list:

Captive-Bred vs. Wild Caught: Captives tend to be easier to give care
Handle-ability and other Pet Qualities: Don’t expect them to be “Friendly”
The “It Doesn’t Do Anything” Factor: Small active species vs. larger docile species
Cost: Initial Purchase Price vs. Price of Ownership
Veterinary Care: Do you have access to a local veterinarian with reptile experience?
Safety: Properly treating bites and Salmonella and avoiding dangerous and poisonous species
Space: Consider your pet’s ultimate size and growth rate
Time Commitment: Ranging from species that require weekly care to ones that require daily attention, along with respect to their lifespans that can reach as high as 50 years
Diet: Ability to handle or accept that many reptiles eat or require dead rodents



Further Reading

The Five Best Pet Snakes

The Best Small Snake Pet

Preventing Salmonella Infections


Turtle Food: Pellets, Shrimp and other Prepared Diets

Painted turtle

Uploaded to Wikipedia Commons by US Bureau of Land Management

Today’s commercial turtle foods are, thankfully, light years removed from the yesteryear’s dried “ant eggs” (actually ant pupae). While natural foods remain important, some remarkable advances now provide turtle keepers with an important safety net, and simplify the process of providing our pets with a balanced diet. Today I’ll review some well-researched prepared diets that are valued by zookeepers and experienced private turtle owners alike.


Note: The excellent products described below should be used as part of a well-rounded diet….in my experience, up to 50% for some species, more or less for others. We do not, as far as I know, have long-term research concerning diets comprised entirely of prepared foods. Whole freshwater fishes remain the best source of calcium for Sliders, Painted Turtles, Snakenecks and most other semi-aquatic turtles. Depending upon the species, fresh greens, produce, earthworms and other foods may be essential as well. Please see the articles under “Further Reading” and post questions below for information on complete diets for specific turtles. Today I’ll focus on Zoo Med products, as they have an extensive product line that is backed by over 2 decades of research. I’ll cover prepared foods from Tetra, Hikari and others in the future.


mediaAquatic Turtle Food

Zoo Med’s Aquatic Turtle Food can be an important building block in the diet of a wide variety of turtles. It was formulated for Sliders, Sidenecks, and Asian Box, Spotted and Painted Turtles, but is also useful for African Mud Turtles, Spotted Pond Turtles and others. I especially like the fact that it is available in both hatchling and adult formulas, with the levels of protein and other nutrients adjusted for each.



This high protein (35%) floating food contains kale along with other animal and plant products, vitamins and minerals. I came to value kale as a turtle food after discussions with veterinarian co-workers at the Bronx Zoo, but find that it is not widely used by private keepers. Mixing it with the tastier foods included in ReptiSticks is also a great way to induce your “meat oriented” pets to eat their vegetables!


Spotted Turtle

Uploaded to Wikipedia Commons by Dave Pape

Freshwater Shrimp

Shrimp play an important role in turtle diets, but until recently only marine species have been available commercially.  However, the shrimp in Zoo Med’s Sun Dried Red Shrimp is freshwater species (the Oriental River Shrimp, Macrobrachium nipponense) and as such is a great food item for most semi-aquatic turtles. Anecdotal evidence from several of my zoo colleagues indicates that shrimp (and krill) are an excellent calcium source for a variety of turtles…and I cannot recall many that will refuse them!


Gourmet Turtle Food

Dried cranberries and mealworms are among the unique ingredients in Zoo Med’s Gourmet Aquatic Turtle Food, which can be used to add variety to the diets of Sliders, Cooters and similar turtles. As always, be sure to feed this and other high protein foods (37% in this product) in accordance with the needs of the species that you keep…please post below for detailed information.


Some Other Ideas

t259648Zoo Med’s Floating Turtle Feeder accepts most pelleted foods, is fun to use, and will keep your turtle occupied and active.   Please see this article for more info.


I’ve long offered commercial turtle foods to various newts, African clawed frogs, shrimp, crayfish and hermit and fiddler crabs. When moistened, many are also readily accepted by millipedes, roaches, crickets and other invertebrates.




Further Reading

Feeding American Box Turtles

Slider Map and Painted Turtle Care and Feeding

Turtles as Pets: New Species to Try in 2014

Turtle enthusiasts are, in my experience, among the most intense of all reptile keepers. Passionate (and financially well-off!) friends of mine have maintained astonishing collections – upwards of 2,000 specimens in several cases – and their desire to learn remains undiminished. In recent years, refined breeding techniques have introduced and re-introduced many fascinating species to the pet trade. Today I’d like to cover several that might interest folks with varying degrees of experience. I’ll review others in the future…until then, please post notes about your own favorites (“new” or “old”) below, as those mentioned here are just a small sample.


Peacock Slider, Trachemys scripta venusta

Peacock Slider

Uploaded to Wikipedia Commons by Magnus Manske

Also known as the Meso-American Slider, this aptly-named beauty truly is the “peacock” of its family, and one of the most spectacularly-colored of all American turtles. Hatchlings must be seen to be believed (unfortunately, the only photo I was able to use does not do the species justice; please click here for other photos), and they fade but little with age. The numerous dark-centered, orange-ringed spots that decorate the olive to bright green carapace are unique in the turtle world, and they are off set nicely by the yellow-striped head and legs.


The Peacock Slider’s range extends from southern Mexico (Veracruz) through Guatemala and Belize to El Salvador and Honduras. Within much of this area, it can be quite common…image having this as your local “pond turtle”! Like its cousin the Red Eared Slider, the Peacock spends much time basking on logs, plunging (or “sliding”) into water when disturbed.


Unfortunately for those with limited space, this is the largest of the 15 Common Slider subspecies, with females sometimes topping 19 inches in length. Otherwise, it is quite hardy and may be kept and fed as are Red Eared and other sliders (please see the article linked below for detailed information). A male (the smaller sex) might get by in a 55-75 gallon aquarium, but females need tanks of 100 gallon capacity, or commercial turtle tubs and ponds.


Keeled Box Turtle

Uploaded to Wikipedia Commons by Torsten Blanck

Keeled Box Turtle, Cuora (Pyxidea) mouhotii

This subtly-beautiful turtle has been largely ignored by hobbyists and zoos alike, but it is now gaining in popularity.


Also known as the Jagged-Shelled or Indian Thorn Turtle, it bears a unique carapace which is flattened on top and decorated with 3 distinctive keels. The shell is clad in varying shades of brown, tan and rust, and is serrated at the rear edge. A hinge in the plastron of the adults allows the head and front limbs to be sealed tightly into the shell. They top out at 7 inches in length.


The Keeled Box Turtle ranges from southern China and eastern India through Vietnam, Thailand and Myanmar. It is not well-studied in the wild, but seems to be restricted to forests and other habitats with thick plant cover.

Interestingly, they are reported to be largely nocturnal. However, a 30+ year-old pair under my care were content to forage by day. Night viewing bulbs will help you observe those that may be slow to give up their nocturnal ways.


Their care follows that of most American Box Turtles (Terrepene spp.), but in demeanor they are much shyer. Mine thrived on a diet comprised of vegetables, fruits, crickets, earthworms, pink mice and commercial turtle chows such as Zoo Med Box Turtle Food.


Pairs must be watched closely, as males often bite females during courtship. A typical clutch contains 1-5 eggs, which hatch after an incubation period of 95-110 days at 82 F. Please see the article linked below for further information.


Yellow Spotted Sideneck

Uploaded to Wikipedia Commons by Obsidian Soul

The Yellow-Spotted Sideneck Turtle, Podocnemis unifilis,

This attractive South American turtle commonly appeared in the US trade in the 1960’s and 1970’s. Scarce in the decades since, it is now making a comeback. It sports a yellow-rimmed, olive-gray carapace, with large, bright yellow or orange-yellow spots decorating the head.


The Yellow Spotted Sideneck inhabits northern and central South America, from Guyana, French Guiana and Venezuela to Columbia, Ecuador, northeastern Peru, northern Bolivia and Brazil; it may also be present on Trinidad and Tobago.


An active, semi-aquatic turtle that reaches 12-18 inches in length, the Yellow-Spotted Sideneck is best kept by those with room for a 100+ gallon aquarium or a commercial turtle tub or pond. Dry basking areas and ample UVB exposure are essential. Youngsters are largely carnivorous, adding plants to the menu as they mature. Zoo Med Aquatic Turtle Food,specifically formulated for Sidenecks and similar turtles, may be used as a cornerstone of the diet. Please see the article linked below for additional information on the natural history and care of this spectacular turtle




Further Reading


Yellow Spotted Sideneck Turtle Care


Keeled Box Turtle Care


Slider, Map and Painted Turtle Care


The Best Small Snake Pet? Suprise! The Brown Snake

Northern Brown Snake

Uploaded to Wikipedia Commons by Westportchickenboy

The first wild snake I encountered as a child, on a dead-end street in the Bronx, measured a mere 10 inches long. However, it excited me as much as did the huge anacondas and pythons I visited regularly at the Bronx and Staten Island Zoos, and the American Museum of Natural History. That particular Northern Brown or DeKay’s Snake (Storeria dekayi dekayi) escaped, but you can bet I searched nonstop until I found another! Happily, this adaptable little serpent continues to hang on in the most unlikely habitats…each year I receive several in need of rehab, collected in busy Manhattan neighborhoods. This overlooked snake has much to offer reptile enthusiasts. It can be comfortably-housed in a 10 gallon tank, does not eat rodents, and it’s the young are produced alive, eliminating the hassle of egg-incubation. Brown Snakes are ideal candidates for naturalistic terrariums stocked with live plants, and when kept so they will exhibit a wider range of natural behaviors than can be expected from large snakes – it’s just far easier to provide them with all that they need. As a career herpetologist, I’ve gone on to care for and observe in the wild the same huge snakes that entranced me so long ago…yet I still maintain Brown Snakes, and watch them in my yard at every opportunity.


Brown Snake Description

Slender and graceful, the Brown Snake averages a mere 9-13 inches in length, although exceptionally-large individuals may reach 20 inches. The largest I recall handling measured 14.5 inches.


Most are clad in various shades of brown (no surprises there!) or tan, but some individuals sport an attractive reddish or yellow hue. Brown Snakes are often confused with Garter Snakes, but may be distinguished by the two lines of black spots that run along their backs.


Range and Habitat

The Brown Snake is one of North America’s most widespread and common snakes. The seven subspecies range from southern Canada through much of the USA through Mexico to Guatemala.


Northern Brown Snake

Uploaded to Wikipedia Commons by Maberlyn

Equally at home in fields, swamps, forest edges or suburban yards, the Brown Snake’s secretive ways also allow it to survive in parks and overgrown lots in urban areas. It is often the first (and, in NYC, the only!) snake to be found and brought home by curious children.


In undisturbed habitats, it shelters below leaf litter, fallen logs and rocks. Big city Brown Snakes utilize old tires, boards, sheet metal and other rubbish as hiding sites, and often do very well if left alone. Not long ago, I uncovered a very dense population sandwiched between a busy commercial area and a major roadway in Queens, NYC. I was once called to a busy Bronx street to remove one that was uncovered when a stoop was being demolished. Given the nature of the area, this individual likely spent most of its life within the concrete channels of that stairway! Amazingly, I’ve also found Red-backed Salamanders living in similar situations.


The Terrarium

A single Brown Snake will do fine in a 10 gallon aquarium; a 20 gallon will support 2-3 adults. The tank’s screen lid should be secured by cage clips.


Unlike most snakes, Brown Snakes do not fare well on newspapers, or in bare enclosures. Their terrarium should instead be furnished with a mixture of a rainforest-type reptile substrate (i.e. Zoo Med Forest Floor Bedding) and coco-husk; I like to add dead leaves as well. Many individuals will shelter below the substrate, but caves, bark slabs and cork bark should also be provided.


Pothos, Chinese Evergreens and other hardy plants, or naturalistic plastic plants, will help your snakes to feel comfortable. Once they settle in, you can expect to see a wide variety of behaviors.


Light, Heat and Humidity

Heat bulbs or ceramic heaters should be used to maintain an ambient temperature of 72-78 F and a basking temperature of 83-85 F.


Both humid and dry areas should be provided. A cave stocked with moist sphagnum moss makes an ideal moist retreat.


Although UVB light is not essential, some experienced keepers believe UVA exposure, and low levels of UVB, may be beneficial for other diurnal, insectivorous snakes. The Zoo Med 2.0 would be a good choice if you wish to experiment.


Brown Snake Breeding

Well-adjusted Brown Snakes often delight their owners by reproducing. Five to thirty young are born alive at various times from spring through fall. Measuring only 3 to 4 ½ inches in length, newborns might easily be mistaken for earthworms were it not for their alert demeanor. A short cooling off period and reduced light cycle may encourage breeding, but this does not seem essential.


Consuming salamander

Uploaded to Wikipedia Commons by Bdempster


The natural diet includes earthworms, beetle grubs, slugs, caterpillars and other soft-bodied invertebrates. In some habitats, Red-Backed Salamanders and the young of other woodland species, and small or newly-transformed frogs, are taken as well (please see photo). Pets do fine on a diet of earthworms, waxworms, calci-worms and butterworms; mealworm pupae, housefly larvae, and canned silkworms are accepted by some individuals. I also collect and offer cutworms and other smooth caterpillars, beetle grubs and slugs (please see articles linked below).


While vertebrate prey is not needed, some believe that insectivorous snakes should be provided with calcium supplements. I’ve not found this necessary for individuals kept on a varied diet anchored with well-fed earthworms. For snakes fed a more limited diet, a once weekly dose of ZooMed Repti-Calcium, or a similar product, might be useful.


Brown Snakes do best when fed several small weekly meals. Allowing earthworms and other invertebrates to establish themselves in the terrarium will provide your pets with hunting opportunities, and yourself with much of interest to observe.



Shy and always on guard (they are on the menus of a great many predators!) these little snakes can rarely even be induced to bite. Stressed individuals may release musk, but most take short periods of gentle handling in stride. However, they are lightly-built and are best considered as a poet to observe rather than handle frequently.



Further Reading


Collecting Insects for Captive Reptiles


Garter Snake Care


The 5 Best Snake Pets

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