Home | 2009 | June

Monthly Archives: June 2009

Creating an “Ant Farm” for Burrowing Amphibians, Reptiles and Tarantulas

Hello, Frank Indiviglio here.  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.

Please write in with your questions and comments.  Thanks, until next time, Frank Indiviglio.

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

The Russian or Horsefield’s Tortoise: an Ideal “First Tortoise”?

Hello, Frank Indiviglio here.  Tortoises are among the most highly-desired of reptile pets, but their care is fraught with difficulties, and captive death rates remain surprisingly high.  The plucky Russian, Horsefield’s or Central Asian tortoise (Testudo horsfieldi) is often promulgated as an ideal “first tortoise”. 

A Cold Hearty Tortoise?

In many regards this is true.  Unlike most of its relatives, the little Russian tortoise is quite cold hearty.  Its range (three subspecies) extends from the southeastern coast of the Caspian Sea through Kazakhstan to western China and south to Iran, and encompasses some very cold regions.  Tortoises living in the north may be active for a mere three months each year.

Living on Little

The Russian tortoise’s adaptation to a Spartan diet also suits it to captivity. Generally, it subsists upon dry grasses, with only limited access to flowers, herbaceous plants and fruits.   Individuals in some populations rarely encounter standing water.

Size

Size also recommends the Russian tortoise as a pet…it tops out at 8.8 inches, and many are considerably smaller. 

Nearly round in profile, the Russian tortoise is pleasantly colored in light to yellowish brown, and patterned with dark blotches.

Some Cautions

For all of the above reasons, it is a Russian tortoise that is often taken home by those new to tortoise-keeping.  Unfortunately, thousands perish each year, often because their owners were initially supplied with misleading advice.

Space and Cage Style

Despite their small size, Russian tortoises are far more active than other reptiles…even the largest of glass aquariums is inadequate.  You must think in terms of a 4-6’ x 4-6’ enclosure.

Glass aquariums, unless ventilated via fan, also do not provide sufficient air flow.  As humidity rises, respiratory problems are a near certainty.

Ideally, these tortoises should be housed outdoors throughout the warmer months.  Outdoor bird aviaries work well, although you may need to install an opaque, plastic barrier along the lower wall edge to prevent climbing. If you must keep your tortoise indoors, a custom-build enclosure is needed (please write in for details).

Environmental Conditions

Indoors or out, Russian tortoises require deep, dry substrates – grass and moist soil will not do.  A mix of sandy soil and oyster shell is ideal.  If unable to construct nighttime sleeping pallets (excavations), Russian tortoises become stressed and subject to dehydration-related disorders.

Pros and Cons

With proper care, the Russian tortoise can indeed be a most responsive and long-lived pet.  However, they are by no means animals to be purchased lightly.  Please consider your abilities carefully, and write in if you have any questions whatsoever. 

I hesitate to discourage responsible people from keeping these fine animals…tortoises ranging from the tiny South African padloper to the massive giants of Aldabra and the Galapagos Islands have provided me with some of my most memorable herp-keeping experiences.  Yet I hesitate to paint too rosy a picture.  Please write in regarding your specific situation, and I’ll do my best to advise you appropriately.  

The Russian tortoise owner must also take into consideration those other factors critical to the care of all tortoises – diet, UVA/UVB exposure, humidity levels, etc.. We’ll take a look at these and other subjects in future articles.  Until then, please write in with your questions and comments.  Thanks, Frank Indiviglio.

Further Reading

Please check out A Complete Guide to Russian Tortoises  in our Reptile Books Department.

An interesting article detailing the natural history of Russian tortoises in a harsh environment is published in the journal Ecography at

http://www.bio.usyd.edu.au/Shinelab/staff/xavier/ecography2003.pdf

Thoughts on Keeping the Giant Bent-Toed Gecko and Related Species – Part 2

Hello, Frank Indiviglio here. Please see Part I of this article for more on bent-toed geckos (Genus Cyrtodactylus; C. louisiadensis and C. irianjayaensis).

UVB and Calcium
Although nocturnal, assume that bent-toed geckos require UVB radiation (others in the genus seem prone to metabolic bone disease). As these lizards generally do not bask at very high temperatures, a fluorescent bulb is preferable. Among florescent models, the Zoo Med 10.0 Bulb  has been shown to consistently deliver the highest UVB output.

To cover all bases until we learn more, I suggest adding extra calcium (along with Vitamin D3) to all food offered. A high calcium supplement can easily be fashioned by mixing Reptivite and Zoo Med Repti Calcium  together in a 1:1 ratio. While this step has not specifically been proven necessary, it has served me well in similar situations.

Snails as a Calcium Source
Many arboreal geckos, Cyrtodactylus included, relish snails, and these seem to be an important source of calcium in the wild.

You can use small garden or aquarium snails, or smaller individuals of those species typically sold for human consumption (i.e. the grapevine snail, Helix pomatia). All can be rather easily reared at home, with the aquatic species being, in general, more prolific.

If you would like to raise your own snails, I suggest the large freshwater snails commonly sold as apple snails in pet stores. They are quite interesting in their own right, so don’t be surprised if you wind up paying them quite a bit of attention! Apple snails lay orange egg cases just above the water line; these are produced year-round, with more being laid as food intake increases. Apple snails feed ravenously, and do well on a diet of Spirulina disks and kale, romaine and other greens. They should also be provided with a piece of cuttlebone  (discard the metal holder provided for use with cage birds) as a calcium source. The young fall into the water upon hatching and grow rapidly.

Any of the small aquatic snails commonly found among aquarium plants can be bred and used as a food source as well.

Most terrestrial snails do not breed quite as rapidly as do apple snails, and temperate species need a cool period (a refrigerator works well) of 2-4 weeks at 38-40 F if they are to reproduce. Most feed readily upon tropical fish flakes, fruit, vegetables and cuttlebone.

Diet
Roaches stimulate most geckos to feed; many also respond with enthusiasm to moths, beetles and other wild caught insects. Please see my article on Raising Orange-Spotted Roaches  for more information.

I believe it to be very important to offer a variety of invertebrates to bent-toed geckos. If at all possible, try to collect local insects…the Zoo Med Bug Napper is very useful to have on hand.

Leave food in the terrarium overnight, and offer grubs, mealworms, wax worms and the like in cups suspended above ground as opposed to releasing them in the terrarium.

Further Reading
Providing reptiles with a varied diet is always important, but never more so than when dealing with bent-toed geckos and other little-studied species. Please see my article Collecting Live food for Reptiles and Amphibians for some tips on providing your lizard with wild-caught invertebrates.

We have a great deal more to learn about these amazing creatures. Please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.

Image referenced from Wikipedia and originally posted by W.A. Djatmiko. Image is NOT the Giant Bent-toed Gecko, but a related species, Cyrtodactylus marmoratus.

Substrates and Shelters for Animals Prone to Intestinal Blockages – Part 2

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 write in with your questions and comments. Thanks, until next time, Frank Indiviglio.

Leaf Litter Invertebrates as Food for Small Insectivorous Amphibians and Reptiles – Part 2

Hello, Frank Indiviglio 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.

Please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.

Scroll To Top