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

The beautifully-patterned American Box Turtles (Terrapene spp.) are very popular among reptile enthusiasts worldwide. They are extremely responsive, intelligent, calm, and may live for 60-100 years…what more could a turtle fan want!  Unfortunately, there are many misconceptions concerning their care.  The following information will enable you to meet their needs…please post any specific questions you may have.

Note: Box Turtle populations have declined drastically. In addition to habitat loss and road-kill, many were exported to foreign pet markets when European tortoises were protected by law.  Please purchase only captive-bred animals.

Natural History

Four Box Turtle species – the Eastern, Spotted, Ornate and Coahuilan – range from southern Canada through most of the USA and into Mexico.  Ten uniquely-colored subspecies, including the Florida, Gulf Coast and Yucatan Box Turtles, are also recognized.

Box Turtles frequent woodlands, marshes, fields, agricultural land, and many other habitats.  Some, such as the Eastern Box Turtle (T. carolina), are largely terrestrial, while Three-Toed Box Turtles (T. carolina triunguis) and others split their time between land and shallow water.  The Coahuilan Box Turtle (T. coahuila), the group’s only truly aquatic member, is found only in Mexico’s Cuatro Cienegas Basin.  Several of my colleagues at the Bronx Zoo studied this species in the wild, and I had the good fortune to work with a breeding group for many years; please look for my future article on this most unique turtle.

Although certain other turtles posses shell hinges that allow the plastron (lower shell) to be drawn up (“like a box”), in no group is this ability so well developed as the American Box Turtles (please see photo). Read More »

The incredible diversity of life in tidal creeks and rivers has attracted me since childhood.  And while invertebrates and fishes predominate, areas where fresh and salt water meet hold wonderful surprises for reptile enthusiasts as well.  Today I’d like to discuss a turtle that I often find in brackish water habitats, and which seems to be evolving unique adaptations to survive there – the Snapping Turtle, Chelydra serpentina.

A Turtle Banquet

The Long Island (NY) tidal creeks (please see photo) that I frequent seem “paved” with crabs, marine worms, snails, bottom fishes, mussels, clams, shrimp and other foods that could be easily exploited by turtles.  In fact, research indicates that at least one marine turtle, the Kemp’s Ridley, actively migrates to the LI Sound, gaining up to a pound per week during the time it remains there.  The Snapping Turtles I’ve seen in such habitats have been quite large, and I can’t help but think that abundance of high quality, easily-caught food must play a role in their presence.

I’ve even been fortunate enough to come upon a family of River Otters in one tidal creek, a species long gone from LI but now making a comeback.  I’ve worked with captive otters, and can attest that if they are present, there’s lots of food about – their appetites are unbelievable! Read More »

The Rosy Boa (Lichanura trivirgata) and several of the Sand Boas (Eryx spp.) are among the most unique of the 53 species in the family Boidae.  They are excellent choices for both beginning and advanced keepers, especially those with limited space.  Stoutly-built but averaging only 24-30 inches in length, these “big snakes in a small package” are hardy, relatively easy to handle and breed, and adapt well to small enclosures.

Natural History

Rosy and Sand Boas have made similar adaptations to their environments, but live on opposite sides of the globe – a phenomenon known as convergent evolution.  Both are highly-specialized burrowers, spending most of their time below-ground in warm, dry habitats.  Along with the equally-unusual Rubber Boa (Charina bottae) and African Burrowing “Python” (Calabaria reinhardtii), they are classified in the subfamily Erycinae. Read More »

The Green Iguana (Iguana iguana) is truly a study in contrasts.  Captive-bred by the millions on farms in Latin America, the 7-inch-long hatchlings are widely considered to be suitable for novice reptile keepers.  Indeed, with proper care, they mature into one of the most impressive and responsive of all reptilian pets.  Yet these tropical lizards have very specific needs that must be met if they are to thrive, and their eventual size (4-6 feet) and potentially aggressive behaviors are serious considerations.

Range and Habitat

The Green Iguana’s range extends from southern Mexicothrough Central America to Paraguay. They also inhabit Puerto Rico, St. Lucia and other Caribbean islands, and have been introduced to Florida and Hawaii (please see this article on Iguana-Raccoon Interactions in Florida).

Green Iguanas are always found near water, into which they plunge when frightened. They are often associated with forested areas, so I was surprised to encounter large populations in Venezuela’s treeless llanos region; please see this article.

Behavior

Green Iguanas are ever-alert, and easily startled by noises, dogs and other threats. They vary greatly in personality – some become docile, while others remain wary of people.

Males may become dangerously aggressive with during the breeding season (please see article below), and either sex may bite, lash out with the tail, or scratch.  The wound on my arm, pictured in the attached photo, resulted from a single flick of the tail (and my skin is generally described as “very leathery”!).  Please write in for information on safe handling.

Housing

Setting up the Terrarium

Enclosure size is a major concern.  Hatchlings will exceed 2 feet in length in their first year, and 3 feet by age 2.  Adults reach 4.0 to 5.5 feet in length, with males sometimes exceeding 6 feet.

Hatchlings may be started in a 30 gallon aquarium, but will need a 55 gallon tank within 12 months.  Once your lizard reaches 3 feet in length, a homemade or commercial cage will be necessary.  An enclosure measuring 6 x 3 x 6 feet tall will suffice for an adult; wheels should be added to allow for sun exposure.  Predator-proof outdoor cages such as modified bird aviaries are the ultimate in “luxury accommodations”.

Green Iguanas are highly arboreal and will be stressed if kept in enclosures that do not allow climbing opportunities.  Stout branches and wooden shelves should be provided.

If an “iguana proof” room is available, out-of-cage exercise time can add greatly to your lizard’s quality of life.

Substrate

Cypress mulch has been used with success, but impactions due to substrate ingestion are possible.  Newspapers, washable cage liners or outdoor carpets are preferable.

Females without access to suitable nesting sites may retain their eggs; please see this article for information on captive breeding.

Light

Green Iguanas will not thrive without a source of Ultra-Violet B light.  Natural sunlight is best, but be aware that glass and plastic filter out UVB rays, and fatal overheating can occur very quickly.

If a florescent bulb is used (the Zoo Med 10.0 UVB Bulb is ideal), be sure that your pet can bask within 6-12 inches of it.  Mercury vapor and halogen bulbs broadcast UVB over greater distances, and also provide beneficial UVA.

Heat

The ambient air temperature should range from 82-95 F, with a basking spot of 95-100 F.  Incandescent bulbs should be used to maintain these temperatures.  A ceramic heater or red/black night bulb can be used after dark.

Humidity

Green Iguanas favor humidity levels of 65-75%, but must be able to dry off as well.  The terrarium should be misted as needed.  A reptile humidifier may be used in especially dry environments.

A large water bowl should be provided for drinking and soaking.

Companions

Males will fight savagely, and females may also battle for dominance.  Juveniles usually get along, but must be watched carefully as they mature.

Feeding

Strict attention to diet is essential if you are to succeed with Green Iguanas.  Nutritional deficiencies can develop quickly, and are difficult to treat. Young iguanas should be fed daily; 2 small meals are preferable to 1 large.  Adults can be fed every-other-day, or provided smaller daily meals.

Greens, Vegetables and Fruit

The majority of your iguana’s food – 60% or more – should consist of a variety of fibrous, calcium-rich vegetables such as kale, romaine, dandelion, bok choy, collards, mustard and turnip greens, beet tops and escarole; broccoli, peas, squash, beans, carrots, peppers and mixed frozen vegetables may be added in smaller quantities.  Spinach binds calcium and should be avoided.

Fruit should not comprise more than 10% of your iguana’s diet.  Bananas, pears, apple, figs, melons, berries, kiwi, peaches and others should be offered.

Boiled brown rice or fiber-rich, sugar free cereals (i.e. Fiber One) may be given as a fiber source. This may not be necessary if a variety of fibrous greens are provided, but serves well as “insurance”.

Protein

In their natural environment, young Green Iguanas consume both insects and vegetation before switching to a plant-based diet as they mature.  While success has been had by using insects as a protein source for young iguanas, most keepers are better off relying upon legumes, such as boiled lentils or pinto, navy and kidney beans.  These should make up 5-10% of the diet until age one, after which time they can be used as occasional treats.

A number of commercial iguana diets are available.  While their long-term use as a sole diet has not been studied, adding some to your iguana’s salad should provide additional nutrients.

Supplements

Most meals provided to growing iguanas should be powdered with a Calcium source such as Zoo Med ReptiCalcium.  Reptivite or a similar vitamin/mineral supplements should be used 2-3 times each week.  The supplementation needs of adults vary; please write in for further information.

Health Considerations

Due to their size, Green Iguanas are sometimes allowed to wander at will about the home.  While a room that has been carefully set up for your iguana (please write in for details) can be useful, free-ranging iguanas present serious health and safety risks.  Chief among these are the potential for fires (dislodged lamps, etc.) and an increased risk of Salmonella transmission.  Please write in for further information. Read More »

Drawn by uneaten food, shed skins and other organic material, ants sometimes become pests around reptile, amphibian and invertebrate collections. As pesticides are harmful to humans and other creatures alike, eliminating ants in areas used by pets and people takes some care.  Today I’d like to highlight a substance that I used with great success in various zoos, and which works equally well at home – diatomaceous earth.

A Most Formidable Insect

Famed entomologist E.O. Wilson has demonstrated that ants “rule” many habitats, driving evolution and other processes to a degree that is hard to imagine.  What little work I’ve done with them has convinced me that they are, at the very least, extremely resourceful creatures. When working with Leaf Cutter Ants (Atta cephalotes) at the Bronx Zoo, I observed a dramatic increase in egg production shortly after empty nesting chambers were added to the colony’s enclosure – the workers somehow communicated to the queen that more space was available, and more bodies were needed. This likely holds true for other species as well – killing a few dozen workers will not reduce ant numbers but instead may set up a call for more eggs! Read More »