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

Reptile and amphibian keepers are fortunate to have at our disposal a huge array of substrates, many of which are formulated for specific animals (burrowing frogs, large snakes).  However, there are still a few situations, usually involving especially sensitive species, where we may need to improvise.  Today I’d like to relate my experiences using “alternative” substrates for desert-dwelling reptiles and hatchling tortoises.  I have long used both while working with animals in zoos, but have noticed that neither is well-known in the pet trade.

The Immune Systems of Desert Dwellers  

Reptiles hailing from desert and semi-desert habitats are often very sensitive to molds and fungi.  Having evolved in unique, relatively pathogen-free environments, their immune systems are usually unable to adapt to attack by microorganisms commonly encountered in captivity.

Potential Problems with Sand

Many of the substrates traditionally used for such creatures, including most types of sand, harbor molds and fungi when damp.  Although not a problem (in limited-contact situations) for all desert animals, some are especially sensitive and quickly succumb to skin and respiratory infections.

Chief among these in my experience are Egyptian tortoises (Testudo kleimanni), padloper tortoises (Homopus signatus, the world’s smallest tortoise) and several of the whip-tailed lizards (Cnemidophorus spp.).

Using Oyster Shell

Oyster shell (available at garden and poultry supply stores) does not support the growth of fungi or mold, is benign when swallowed in small amounts, and can be easily spot-cleaned and discarded when fouled.  I cannot recall any skin or respiratory problems in desert-dwelling reptiles maintained on oyster shell.

Further Reading

You can read more about fungal and other respiratory ailments in tortoises at: http://www.azeah.com/Care-Sheets.asp?id=125

Tortoise photo referenced from Wikipedia and originally posted by Stefano Alcini.

I received my first “Uncle Milton’s Ant Farm” at about age 6, and instantly realized that therein lay the keys to a world previously closed to me (incidentally, Uncle Milton’s Ant Farms are still on the market, complete with decorative green plastic farmhouses and a coupon for live ants!).  My interest in subterranean creatures soared, and I soon had farms stocked not only ants but also earthworms, beetle grubs and even mole crickets.

From Ants to Gerbils

My introduction to using ant-farm type enclosures for other animals came a few years later.  Mongolian gerbils had just entered the US pet trade, and I became fascinated with these social, burrowing rodents.

In preparation for receiving my first pair of gerbils, I read all that I could get my hands on.  This amounted to a single care pamphlet – but within its pages I read about a burrow system designed by the author.  By inverting one aquarium (bottom side up) inside a larger tank, the author encouraged the rodents to burrow along the front glass.  When they emerged, the active little fellows had use of the entire large enclosure, since the bottom of the inverted tank, covered with soil, served as a substrate.

Fossorial Herps and Invertebrates

Starting with my own collection and refining the system while working at the Bronx and Staten Island Zoos, I found the basic premise widely applicable to fossorial (burrowing) creatures of all types.  The burrows are essentially sandwiched between 2 panes of glass, allowing for easy viewing through one side.

I especially like this set-up for eastern spadefoot toads, marbled salamanders, Australian water-holding frogs and fossorial tarantulas, scorpions and centipedes.  In the terrariums and zoo exhibits typically used for such creatures we are fortunate to get an occasional glimpse of anything approaching natural behavior.  However, displayed as described above, they reveal a great deal about their fascinating life histories.

Refinements

Tarantulas often line terrarium glass with silk, thwarting our efforts to observe them.  However, they are less likely to do this if you cover the outside of the glass (that portion that fronts along the burrow) with black paper or cardboard, hinged at the top with tape.  If you lift this gently, the spider may remain on view.

This technique is also useful for other high-strung creatures.  At Tokyo’s Ueno Zoo, I noticed that fossorial voles were very nicely displayed in an ant-farm type enclosure.  A hinged wooden door was used in place of the black paper described above, allowing visitors a peek at the rodents going about their business below-ground.  I have also successfully used the tank-within-a-tank system in zoo exhibits for dune mole rats and African pygmy mice.

Useful Products

Many burrowing animals are not only shy but nocturnal as well.  A night-viewing bulb  will help in observing them.

Substrate composition will vary, depending upon the species that you keep.  Two very useful products for burrowing animals are R Zilla Coconut Husk  and Zoo Med Repti Sand. Experiment with moisture levels until you have a composition that supports permanent burrow systems.

Further Reading

Some years ago I acquired a group of Australian water-holding frogs (Cyclorana platycephala) and found them to be among the amphibian world’s most accomplished burrowers.  To learn more about these amazing creatures, please see http://animals.jrank.org/pages/181/Amero-Australian-Treefrogs-Hylidae-WATER-HOLDING-FROG-Cyclorana-platycephala-SPECIES-ACCOUNTS.html.

Water holding Frog image referenced from Wikipedia and originally posted by Haplochromis

Please see Part I of this article for background information on substrate and food related intestinal impactions, including some interesting stories from the field.

Substrates for Aquatic Animals
Surinam toads, mata-mata turtles, axolotls, mudpuppies and other wide-mouthed aquatic animals that utilize suction (the flow of water into the gaping mouth) to capture prey quite frequently swallow gravel in the course of feeding.

If you do not care for the look of a bare-bottomed aquarium, our life-like Cypress Mat is well worth considering as a bottom-covering. It cannot be swallowed, is easily rinsed, and many animals will nestle down into it as a shelter. I suggest leaving a bit of the aquarium’s bottom uncovered by the mat until you can determine where your animals prefer to remain.

Sinking driftwood and Mopani wood are also safe to use, and will go a long way in improving your aquarium’s appearance.

Shelters for Burrowing and Aquatic Animals
Artificial and wood-based caves and hideaways are often accepted as substitute shelters by burrowing animals; plastic models are fine for use in aquariums as well. If so inclined, you might also enjoy using novelty decorations and shelters for pets prone to ingesting gravel and sand.

Cork bark pieces and rolls make fine shelters for terrestrial herps, and may be wedged against the aquarium’s sides to form an underwater retreat as well.

Hagen Silk Plants  are an excellent option for African bullfrogs, marine toads and other large animals that prefer to back into vegetation or moss as opposed to using a cave. These plants are equipped with suction cups, and when arranged to hang down to the terrarium’s floor they provide a naturalistic retreat. They can be used in a similar fashion under water – Surinam toads in particular prefer this arrangement to a cave.

Tong-Feeding and Separate Feeding Enclosures
Training your pets to feed from tongs will also go a long way in avoiding substrate-swallowing problems. Use plastic tongs for animals with a vigorous feeding response and reserve metal tongs for those that feed gingerly or accept large food items.

Well-acclimated reptiles and amphibians often feed eagerly even after being transported to a separate feeding container. Transferring such animals to a bare-bottomed plastic terrarium or similar enclosure is a useful feeding option.

Further Reading
The Manuel of Exotic Pet Practice’s entry on intestinal impactions is posted here.

Please see Part I of this article for further information.Last time we took a look at the amazing diversity of tiny invertebrates that inhabit leaf litter, and their importance as food for small terrarium animals such as poison frogs, dwarf leaf chameleons, and young frogs, lizards, mantids and scorpions.

Collecting Leaf Litter Invertebrates
As mentioned in Part I of this article, the springtails, ants, mites, millipedes and other creatures inhabiting a single acre of fallen leaves can add up to an astonishing 3 tons in weight! So how do we harvest all of this free food?

A technique borrowed from professional entomologists (insect scientists) works quite well. Simply place a handful of leaf litter into a funnel, suspend the funnel over a jar and position a 100 watt bulb about 6 inches above the leaves. The heat will drive the resident invertebrates down the funnel and into the jar. A damp paper towel placed at the bottom of the collecting jar will assure that the more delicate animals survive.

Using Wild-Caught Invertebrates
Remove potentially dangerous animals such as biting ants and centipedes, and dispense the rest to your poison frogs, baby anoles and other such creatures. Their reactions to this novel food will convince you of its worth – most terrarium animals become noticeably excited and feed ravenously each time they are presented with novel prey species.

Use Petri dishes if you prefer to keep your pets’ meals confined to one area. Springtails, sowbugs and others may colonize the terrarium substrate if allowed to disperse, which is also useful in some cases. You can also place small piles of leaves directly into the terrarium (after checking for dangerous species) – its great fun to watch frogs and other creatures search through them for tasty snacks.

Zoo Experiences
Others far more inventive than I came up with this technique, but I have long championed it in my articles and books…usually without much luck! Even among my zoo co-workers, my pleas fell on deaf (if amused!) ears.

So, upon touring several zoos in Japan recently I was thrilled to learn that several keepers, after reading about the topic in a book that I wrote some years back (Newts and Salamanders, which for some reason is popular in Japan), tried it out. Their results were so positive that the technique is now a regular part of the husbandry regime in several collections!

Trapping Tiny, Flying Insects
The Zoo Med Bug Napper, a very effective insect trap that I rely upon throughout the warmer months, will attract tiny gnats, moths, beetles and flies along with larger insects. These too make fine foods for your smaller pets.

Further Reading…Meadow Plankton
“Meadow plankton” is a term given to the myriads of insects and other invertebrates that can be gathered by sweeping a net through tall grass in fields and in overgrown areas along roads, farm edges, parks, etc. These creatures can also be fed to smaller reptiles, amphibians and invertebrates. Please look for my future article on this topic.

Until then, a partial species list of insects that might be encountered in a typical temperate zone meadow, along with other information, is available on the website of the Invertebrate Conservation Trust.

A surprising number of largely carnivorous lizards, especially various geckos and anoles, consume sap, flower nectar and overripe fruit in the wild. Providing a substitute in captivity is a good way to increase dietary variety. Also, as many find sweet liquids irresistible, by mixing in vitamins and minerals you can help ensure a nutritious diet.

Sugar Water to Nectar Mix
Well, we’ve come a long way since the anole “sugar water days” (the recommended diet for green anoles sold at circuses in the 1960’s). Following is a mix that I and others have found useful for anoles, geckos, basilisks, skinks and others.

1 jar of fruit-based baby food (papaya, banana, apricot or mixed)
1 tablespoon of honey (alternate with molasses)
1 dropper of Avitron Bird Vitamins (although formulated for birds, Avitron is a tried and true ingredient)
1 teaspoon Repti Calcium (without D3)
Water should be added to achieve a consistency favored by the species that you keep – i.e. nearly solid for New Caledonian giant geckos, watery for Jamaican anoles.

Additional Notes
Some folks add bee pollen, which seems not to affect palatability, and may add useful nutrients.

Experiment with different flavors, as some species are quite particular. Try also adding some mashed, overripe bananas, oranges, mangos and other fruits to the mix (for giant geckos, this is a must).

Nectar for Beetles, Roaches and Moths
If you are like me and favor invertebrates as well, you’ll find this mix very useful in keeping Hercules, goliath, rhinoceros, stag and other tropical and native beetles.

Most roaches devour it eagerly. I have used this and similar mixes to quickly nutrient-load roaches destined to be fed to delicate captives, and for Cuban green and other species in zoo exhibits.

As a side note, if you enjoy observing moths, or collect them as food for your animals, try smearing a tree trunk with honey or molasses. This old insect-collector’s trick has yielded me huge, spectacular Cecropia and polyphemus moths right in the heart of New York City!

Prepared Nectar Mixes
Nectargold for Lories and Lorikeets is a highly nutritious multi-fruit nectar mix. It is supplied dry, and so can be stored until needed. Many creatures will accept it as is, or you can tweak the recipe with honey or other favorites.

Further Reading
Some anoles take nectar so regularly that they may actually function as important plant pollinators. For more information, please see the following note in Herpetological Review

Rhacodactylus leachianus image referenced from Wikipedia and originally posted by Alfeus Liman.