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

The tadpoles of American Toads (Bufo/Anaxyrus americanus) and Fowler’s Toads (B. woodhousei fowleri), and of related US natives, are frequently collected by herpers young and old and taken home to raise.  They usually prove quite hardy, and, even on nutrient-poor diets (i.e. lettuce), transform into tiny toadlets within a few weeks.

Toad Maladies

Young toads often prove difficult to raise however, and each year I receive questions concerning the same 2 problems – bloating and paralysis (difficulty hopping, problems catching food, etc.).  I’ve run across this myself when raising American toad tadpoles for a release program in NYC, where most of the tadpoles transformed, but died soon after.

Nutritional Deficiencies

I’ve come to believe that 2 distinct problems are at work.  Difficulty in using the rear legs is probably linked to deficiency in calcium or another nutrient, but efforts to reverse it, at least in small toads, have proven unsuccessful.
Using supplements on the food given newly transformed toads helps, but we really do not know what most species, especially North American natives, actually require.
Tadpole nutrition is another area that needs investigation.  Poorly nourished tadpoles may transform, but then die several weeks later…I’ve had this happen on a number of occasions over the years, with several species, even the relatively indestructible African clawed frog (Xenopus laevis).

Bacterial Infection

Bloating is usually a byproduct of a bacterial infection, and may be connected to nutrition.  Toads already weakened by a nutritional deficiency may be more likely to become infected with bacteria that healthier clutch mates fight off – hence both symptoms in 1 toad.  This is based mainly on anecdotal evidence, but does seem to happen time and time again, and with several species.

Natural Mortality

Another point to bear in mind is that, among species that lay huge clutches, a great many tadpoles will not survive even under the best of circumstances.  Some turtles lay infertile eggs, apparently to satiate predators and take attention away from viable ones – I have no hard evidence, but I would not be surprised to learn that weaker tadpoles serve a similar function.

Feeding Tadpoles and Young Toads

Most native toad tadpoles are omnivorous.  Try to provide them with as much variety as possible, and bear in mind that, in large groups, smaller, weaker individuals are easily out-competed at feeding time.  I’ve had good luck raising tadpoles on a diet comprised of tropical fish food flakes, algae tablets and kale pre-soaked in hot water (this breaks down thick cell walls). Metamorphs (newly transformed toads) consume scores of species of leaf litter invertebrates in the wild, complicating our job in raising them.  In addition to tiny frog standards such as fruit flies, springtails and pinhead crickets, you might try collecting tiny invertebrates as toad food (please see article below).

Further Reading

Please see my article Leaf Litter Invertebrates for information on collecting live food for tiny amphibian pets.

 Haswell’s Frog tadpole image referenced from wikipedia and originally posted by LiquidGhoul

Hello, Frank Indiviglio here. It’s hard for snake enthusiasts not to be taken in by the Eastern hognose snake, Heterodon platyrhinos. It puts on an incredible defensive display, it’s stout, viper-like body is variably patterned in many hues and its natural history is quite unique. However, a preferred diet of toads precludes it from becoming well-established in captivity. The Western hognose snake (H. nasicus), however, shares many of its eastern cousin’s outstanding qualities, yet has a wide appetite that is easily satisfied in captivity.

Physical Characteristics

Stoutly built with strongly keeled scales and an upturned snout; tan, brownish-yellow or grayish-yellow in color, with dark blotches; reaches 16-36 inches in length.

Range

Central and western North America, from southern Canada through Arizona and Illinois to northern Mexico (San Luis Potosi).

Habitat

Prairies, farms, sparsely wooded fields and semi-deserts, usually in areas of sandy soil suitable for burrowing. Western hog nose snakes spend much time below ground.

Reproduction

Mating occurs from March to May, with 9-25 eggs being laid in June –August. The young, 6-7 inches in length, hatch after an incubation period of 45-54 days.

Diet

In the wild, Western hog nose snakes take young ground nesting birds, mice, shrews, toads, lizards, snakes and reptile eggs. In one study, they were found to be a major predator on Pacific pond turtle nests.

Those I’ve kept have done very well on small mice and quail eggs.

Other Interesting Facts

This snake’s upturned snout (modified rostral scale) assists in digging for fossorial prey such as toads and the buried eggs of turtles and lizards. Specially modified teeth allow the hognose snake to puncture toads and defeat their defense mechanism of inflating themselves with air.

The western hognose puts on a less elaborate display when threatened than does its eastern relative. It will, however, spread the head in hood-like fashion and strike, and will sometimes play dead when this bluff fails. Animals feigning death roll onto their backs with the tongue lolling out, and will flip onto their backs if righted during the process!

Eastern Hog Nose Snake Conservation

I have been involved in a re-introduction program for the eastern hognose snake at Jamaica Bay Wildlife Refuge in NYC. In this area, it inhabits open beaches and sand dunes…please see the accompanying photo. I’ll write about this interesting program in the future.

Please see Part I of this article for general information on some of earth’s most toxic amphibians (if not creatures in general) and for additional newt-keeping observations.

Tiny Newt vs. Giant Toad

The familiar red-spotted or Eastern newt (Notopthalmus viridescens) is at its most toxic in the immature eft (land) stage, but the aquatic adults are none-the-less well protected.

Decades ago, the mascot of an animal importer for whom I worked was a huge marine toad (Bufo marinus).  In those days, animals imported from then French Guyana were particularly massive, and this friendly, 4 pound+ specimen was no exception.  Imported animals which did not thrive following their long journey to the USA, ranging from giant Vietnamese centipedes to small rats and finches, all went to filling this amphibian behemoth’s huge appetite.

As a naïve 13 year old animal caretaker, I once tossed a nearly dead, 3-inch- long Eastern newt to the toad.  The newt was swallowed immediately and, right before my eyes, the toad flipped over…dead (along with my budding career!).  Years later, a co-worker reported a similar incident involving a Western painted turtle (Chrysemys picta bellii).

Interesting Means of Toxin Introduction

Several salamanders have quite unique ways of distributing their protective secretions – fire salamanders (Salamandra salamandra), for example, can squirt theirs for some distance.  Perhaps strangest of all, the Spanish ribbed newt (Pleurodeles waltl) actually drives toxin-tipped ribs through the skin of its back when confronted by a predator!

Cautions regarding Pet Newts and Salamanders

Highly toxic newts and salamanders, including all mentioned in this article, are widely available in the pet trade.  Many make interesting and long-lived pets.  However, please treat all newts and salamanders with caution…always wash well after handling them (most need not be handled, and none appreciate it) and, of course, do not trust them around children, mentally challenged persons, or pets.

Further Reading

Please check out my book Newts and Salamanders  for more information on the natural history and captive care of red-spotted newt, ribbed newts, fire salamanders and their relatives.

Image referenced from Wikipedia and originally posted by Peter Galaxy.

Having been chased by a Kodiak bear, confronted by an escaped king cobra and otherwise molested by scores of formidable animals, I felt relatively secure in accepting responsibility for a group of arboreal South American millipedes entrusted to me by colleague about to travel abroad. A primatologist, she had observed capuchin monkeys to rub millipedes over their bodies, and was investigating the situation (I, on the other hand, have always been far more interested in millipedes than monkeys!).

Deadly Millipedes?

A week after her departure, another coworker phoned me at 4 AM, frantically speaking in the rapid fire Spanish typical of her native Venezuela…and which I have great difficulty in grasping at 4 PM, much less 4 AM! Eventually I learned that 3 elderly millipede researchers had passed away recently, and that preliminary evidence indicated that cyanide poisoning, courtesy of the millipedes’ defensive chemicals, was suspected. I was warned against handling the millipedes (which I had been doing for weeks!) or putting them near my face (which I do not do with any creature).

The deaths turned out to be coincidental and unrelated to millipedes, but the incident led to a good deal of research into the defensive chemicals produced by these popular terrarium pets. It seems that millipede toxins are a very unique and complicated group of compounds.

Exploiting Millipede Toxins

Interestingly, a number of species of frogs and monkeys harness these chemical weapons for their own use. Although lagging behind such creatures by a few million years, humans are also getting into the act, and we may soon be putting millipede secretions to medicinal use.

An Amazing Coincidence!!!

The incident I related above, concerning myself and the millipedes, transpired approximately 8-10 years ago. I’m not sure why I decided to write about it today, but I’ve had millipede articles on my mind for some time, and thought this would make a nice introduction to the topic.

After writing this article I searched for a reference to add, for those readers who wished to learn more. You can imagine my shock when I discovered that today’s NY Times (28 June 2009) carries an article about the very same monkeys, people and millipedes involved in my story!!!

To read the entire article, please go to http://www.nytimes.com/2000/12/05/science/05MONK.html?pagewanted=print.

Next time I’ll explore the nature of these defensive weapons and the uses that monkeys, frogs and people are finding for them. Following that we’ll take a look at keeping and breeding millipedes in captivity.

Image referenced from Wikipedia and originally posted by Prashanthns.

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