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

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).

The success that hobbyists have had in establishing breeding populations of so many species of poison frogs is truly astonishing, and has served a greater purpose in removing the financial incentive to collect them from the wild.

Unfortunately, the extraordinary parental care supplied by many poison frogs is difficult to observe in captivity, and the most effective way of rearing the tadpoles is to remove them from their parents’ terrarium. I was most fortunate to have had the opportunity to observe the breeding behavior of wild strawberry poison frogs in Tortuguero, Costa Rica, and in a large zoo exhibit.

Finding and Feeding the Tadpoles
Strawberry poison frog tadpoles, which are moved by the female frog to individual water-filled bromeliad stems, exhibit what has been termed “begging behavior” when their mother visits their pools. When the female lowers her vent into the water, the tadpole moves against her, stiffens, and vibrates. This stimulates the female to release 1-5 unfertilized eggs, which comprise the tadpole’s sole diet.

She visits and feeds each of her offspring, every other day or so, for the 43-52 days that they remain in the tadpole stage…no wonder these tiny moms eat so much! When one considers the complexity of the frog’s rainforest environment, especially as compared to the size of the frog, the female’s ability to locate each tadpole borders on the unbelievable.

Additional Behaviors
Outstanding herpetologist Elke Zimmermann (in “Breeding Terrarium Animals, 1986. TFH: Neptune City, NJ) has even observed females to dip their heads into bromeliad pools before laying, and notes that disturbances from other than the mother frog sends the tadpole into retreat. Field research in Panama indicates that female strawberry poison frogs consistently avoid feeding other than their own progeny.

I was able to observe parental care only in huge exhibits and the wild, but please write in if you would like to try at home…it’s well worth the effort.

We now know that Chirixalus eiffingeri, a treefrog endemic to Taiwan, also communicates with and feeds its tadpoles. The abstract of an article documenting this behavior is posted at:
http://www.ingentaconnect.com/content/brill/beh/2000/00000137/00000001/art00009?crawler=true

Today I’d like to take a look at a much-maligned food insect that can, if used properly, be an important addition to your pets’ diets.

Mealworms (larvae)
A steady diet of mealworms (I refer here to the small mealworm, Tenebrio molitor, not the giant mealworm, Zophobus mario) is not recommended for any reptile or amphibian. These beetle larvae lack essential nutrients, the calcium: phosphorus ratio is not ideal and the exoskeleton is high in chitin. Mealworms also have quite strong jaws, and may injure debilitated or small reptiles and amphibians.

However, newly molted mealworms, which are white in color, are soft, have weak mouthparts and lower chitin levels. I have found them to be an excellent supplementary food for amphibians, tarantulas, scorpions and reptiles and fish.

Mealworms will shed most frequently when fed heavily and kept at 76-80 F. I house my colony in a mix of wheat bran, corn meal and powdered multi-grain baby food, with a bit of Tetramin Flake Fish Food added in, and provide banana skins for moisture.

Mealworm Pupa
Mealworm pupae are a fine food for turtles, newts, aquatic frogs and those lizards that accept non-living food items. They are low in chitin and likely have a different nutrient profile than either the larvae or adults.

Mealworm (Darkling) Beetles
Beetles, comprising the world’s largest animal family, figure prominently in the diets of most insectivorous reptiles and amphibians (based upon stomach content studies). I have long used darkling beetles (adult stage of the mealworm) as a food item, and prefer them over the larvae in most situations.

Beetles newly emerged from the pupae are softer than later-stage animals, and brown in color. To ensure a steady supply, I remove pupae as they form and place them into a bare container. In this way the beetles cannot burrow into the substrate, and are thus easier to harvest. Warm temperatures and a good diet (see above) will ensure a steady supply. Be sure to leave some beetles in the colony for breeding purposes.

You can learn more about the specifics of the mealworm’s life cycle at:
http://lawrencehallofscience.org/foss/fossweb/teachers/materials/plantanimal/tenebriobeetles.html

Image referenced from Wikipedia: http://en.wikipedia.org/wiki/Image:Mealworms_in_plastic_container_of_bran.jpg

Socially Influenced Mating behavior
Ever wonder how a male frog might draw the attention of a female when he is calling amid hundreds of others? Research published in the August, 2008 “Journal of Comparative Psychology” has revealed that gray treefrogs vary their calls in response to social situations. When alone or in small groups, males utilize the species’ usual call. However, when trying to attract a mate amid large groups, males will vary the rhythm of their calls, in order to stand out from the crowd.

The Only Ultrasonic-Sensitive Frog
Concave-eared torrent frogs have, as one might guess from their name, recessed eardrums. Biologists looking into why this species’ eardrums are not level with the skin, as in most other frogs, discovered that these natives of central China emit and hear ultrasonic mating calls. This is likely because noise from the rushing streams along which they dwell would drown out calls emitted in the lower sound ranges (which are used by most frogs). Until now, only bats, whales and certain insects were thought to utilize ultrasonic calls.

Unusual Ears
And why the recessed eardrums? As stated in an article published in the May, 2008 issue of “Nature”, the torrent frogs eardrums are only 1/30th as thick as the eardrums of other frogs (which are, I imagine, quite thin themselves!) – an adaptation to allow the detection of ultrasonic sound. Their recessed location is thought to confer some protection against injury.

You can learn more about the concave-eared torrent frog’s natural history at:
http://amphibiaweb.org/cgi/amphib_query?where-genus=Odorrana&where-species=tormota

Image referenced from Wikipedia, http://en.wikipedia.org/wiki/Image:Hyla_versicolor.jpg, and taken by LA Dawson

Click:The Green Anole (Anolis carolinensis carolinensis) in the Wild and Captivity; – Natural History – Part 1 to read the first part of this article.

Introduced Anoles
The green anole is the only anole native to the USA, but eight other species, originating as escaped or released pets, have established breeding populations here. The most common and widespread is the brown anole (A. sagrei), now found throughout Florida and in southern Georgia, Alabama, Louisiana, Texas and Hawaii. In many areas it is now more commonly encountered than the green anole.

The knight anole (A. equestris), bark anole (A. distichus), large-headed anole (A. cybotes), Hispaniolan anole (A. chlorocyanus), Cuban green anole (A. porcatus) and Jamaican giant anole (A. gormani) are limited to the vicinity of Miami and Miami-Dade County at this time.

Ill Fated Pets
Green anoles were sold by the millions at carnivals, circuses and through the mail in the 1960’s and early 70’s. Termed “chameleons” due to their color changing abilities, most were fed “sugar water” and expired in short order.

Color Change – not as obvious as it seems
Color change in the green anole has little to do with the background upon which the animal rests (although the colors it exhibits are usually cryptic). Cool or stressed anoles are brown in color, while warm, resting individuals are pale green and warm, active animals are bright green. Anoles involved in aggressive displays develop a black patch behind the eyes.

Unique Climbing Aids
Green anoles are assisted in climbing by transverse lamellae on the bottoms of the toes and feet. These thin structures are divided by thousands of grooves, and provide excellent traction against tiny irregularities in the surface upon which the lizard is moving. Utilizing the lamellae, anoles can even grip dirt particles lodged on glass, and hence climb window panes and aquarium sides easily.

Cold Tolerance and its Conservation Implications
Research has demonstrated that anoles from south Florida lack the cold tolerance exhibited by those in north Florida, and could not survive the winters there. Information such as this is vital in planning reintroduction and captive breeding programs for animals with large ranges. Inter-breeding animals that originate in widely different parts of their range can have disastrous consequences, despite the fact that they are of the same species.

In one case, ibex (mountain dwelling goats) from several European countries were released in the Pyrenees Mountains, to bolster the local population. The animals reproduced, but the offspring resulting from the crossing of native and non-native ibex were genetically programmed to give birth in mid-winter, and the population eventually became extinct.

An interesting summary of research being conducted on free-living green anoles by students at UT Knoxville is posted at:
http://eeb.bio.utk.edu/echternacht.asp