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The Green Anole (Anolis carolinensis carolinensis) in the Wild and Captivity – Care in Captivity Part I

Please see Green Anole Natural History for information concerning the natural history of the green anole and its relatives.

Green AnolesGreen anoles became a US pet trade staple in the 1960’s and early 70’s. Labeled “chameleons” due to their color-changing abilities, millions were collected in Florida and Louisiana and sold at circuses, fairs, pet stores and through the mail. In time, they became the “first lizard” for a generation of budding herpetologists. A host of grossly inappropriate supplies (including lapel chains!) and husbandry techniques assured most of the unfortunate creatures a short and unhappy captive existence.

My Less-Than-Promising Start
I remember well purchasing a green anole (packaged, oddly enough, in a small pie box) at the famous Ringling Brothers, Barnum and Bailey Circus at Madison Square Garden in the early 60’s. I knew enough to bypass the recommended diet of “sugar water and dried ant eggs” but was ignorant of the beast’s UVB requirements. I did, however, gather that it craved sunlight, and during one basking trip the lizard escaped up a caterpillar- laden apple tree where, I hope, it at least enjoyed the NYC spring and summer.

A Bit Delicate, but Well-Worth the Effort
Green anoles do reasonably well in captivity but are not the hardy, “starter lizards” they are often proclaimed to be. They are prone to stress-related ailments, require careful attention to the diet, and are quite sensitive to light, temperature and humidity levels.

That being said, I feel that their potential is largely ignored – a properly maintained group will readily display numerous social interactions, and makes as active and interesting a lizard exhibit as can be imagined. What’s more, establishing a colony of green anoles in such a situation is well within the financial and space constraints of many pet keepers, which cannot be said of most lizard species.

My co-workers at the Bronx Zoo frowned when I began adding green anoles to several large exhibits, but they (the lizards, not co-workers!) quickly became crowd pleasers. Even in an exhibit housing 2 huge water moccasins, it was the leaping, displaying anoles that drew most of the public’s attention.

Enclosure and Physical Environment
Green anoles are highly arboreal and will prefer the upper reaches of their enclosure. Branches of various thicknesses and orientations should be provided, along with plentiful sight barriers in the form of suspended live or artificial plants.

Despite their small size, green anoles require a good deal of room, as they are very active and are easily stressed by tight quarters or if confined too closely to one another. Ideally, a trio should be provided with a well-planted, 20 gallon aquarium.

Males are intolerant of each other. If several females are kept, horizontal and diagonally oriented basking sites (these are preferred over vertical branches) should be plentiful, as dominant animals will exclude others from these important areas.

Anoles do best in complex exhibits, especially those with live plants. They are quite easy on live plants, and really do look at their best when among them. Snake plants, pothos, Philodendron, peace lilies and many others will be well-used by these little gymnasts, and the areas between large leaves make naturalistic nocturnal retreats.

Arboreal shelters, in the form of cork bark and hanging plants, should be provided. These and similar sight barriers are important, as females will establish a dominance hierarchy, and subordinate animals may be inhibited from feeding or basking, even absent outright aggression.

The substrate should hold a bit of moisture but not be soggy. I recently used Exo-Terra Jungle Earth with a covering of Compressed Frog Moss and dead leaves in a public exhibit, and am pleased with the results. You can also use Keeper’s Choice Red CypressExo-terra Forest Bark or Coconut Husk, with any type of moss mixed in.

Click here: The Green Anole (Anolis carolinensis carolinensis) in the Wild and Captivity – Care in Captivity Part 2, to read the rest of this article.


Product Review: The Zoo Med Reptisun 10.0 High Output UVB Lamp and 5.0 UVB Lamp – Part I

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
Can o Shrimp 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).

“Begging Behavior” Among Tadpoles of the Strawberry Poison Frog, Oophaga (formerly Dendrobates) pumilio

Strawberry Poison FrogThe 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:

Making the Most of the Mealworm: some tips on enhancing the nutritional value of this pet trade staple

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)
MealwormsA 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:

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

Research Update: Gray Treefrog (Hyla versicolor) Calls are Influenced by Social Factors, Concave-Eared Torrent Frogs (Odorrana tormota) Call in the Ultrasonic Range

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:

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

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