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My Animal Collection: How a Herpetologist Keeps American Toads, Bufo (Anaxyrus) americanus and Related Species, Part II

Click: My Animal Collection: How a Herpetologist Keeps American Toads, Bufo (Anaxyrus) americanus and Related Species, Part I, to read the first part of this article.

Temperature

American ToadAmerican toads are, in contrast to many amphibians, quite resilient in terms of temperature tolerance.   However, they do best at moderate temperatures, and in the heat of summer will attempt to burrow below the substrate.  Mine are kept at room temperature, which ranges from 62 F in winter to 78 F in the summer.  During particularly hot spells, I move them to an air conditioned room or the cool basement.

Naturalistic and “Hybrid” Terrariums

Toads also adapt well to planted, naturalistic terrariums.  A substrate of top soil and peat moss will allow them to construct burrows, which will be used repeatedly by the same animals.  Cover the soil with one of the moss-based products listed above and dead leaves in order to retain moisture.

A “hybrid” type set-up combines certain features of both styles described above.  A substrate of smooth aquarium stones (1/2 inch size or larger, to prevent ingestion) allows for live plants but deters burrowing (see photo).

R-Zilla Rock Dens serve well as shelters in such terrariums, or you can create your own using cork bark or rocks.  When designing rock caves, consider that the toads may injure themselves if able to burrow and collapse the structure.  Exo-Terra Terrarium Plants are extremely life-like and can be used to good effect in naturalistic terrariums as well.

A Terrarium for Public Display

I designed the gravel-base terrarium shown in the accompanying photo for a museum in New York City.  Zoo-Med Terrarium Moss is mixed into the gravel, which itself sits on an Under-gravel Filter Plate.  A drain cut into the tank’s glass bottom allows the entire terrarium to be hosed down.  A water reserve is kept below the under-gravel plate, creating a damp but not wet environment for the resident toads and salamanders.

Feeding American Toads and Their Relatives

Wild Caught Invertebrates

From spring through fall, I feed my toads exclusively upon wild-caught invertebrates.  A Zoo Med Bug Napper yields plenty of moths and beetles, and easily meets their needs.  However, I enjoy poking around, and so also collect tree crickets, sow bugs, harvestman (“daddy longlegs”), millipedes, termites, earthworms, field crickets and caterpillars whenever I am able.  I feed the toads just about every day during the summer (2-3 small insects each) and 2-3 times weekly when temperatures drop.

I avoid spiders, fireflies, ladybugs and brightly-colored insects, due to possible toxicity problems, and do not collect for a week or so after the area has been sprayed to control West Nile virus.

Commercially Available Insects

During the winter, I keep breeding colonies of sowbugs, earthworms and mealworms as a food source for my collection (regarding mealworms, feed toads only newly molted, or white grubs, and beetles).  The balance of the diet is made up of crickets, roaches, waxworms and butter worms.

Training your pet to tong-feed will go a long way in helping you to introduce dietary variety.  By doing so, I have been able to add Zoo Med Canned Caterpillars and Grasshoppers to my toads’ diets.

I powder feeder insects with a Tetra Repto Cal Supplement once weekly during the winter.  I’ve found that such is unnecessary in summer, when wild caught invertebrates dominate the diet.

Some Thoughts on Prey Size

I have always believed that American toads are designed, by mouth structure and feeing behavior, to take smaller-sized prey than do similarly-sized frogs (i.e. the green frog, Lithobates clamitans).  Even when feeding adult toads, I rarely use insects larger than a ½ to ¾ grown cricket.  Toads under my care are still thriving in their late 20’s and, while I cannot document such, I believe that prey size may be a contributing factor.

 

I’ve written other articles on toads and on amphibian care in general.  Please check out the following when you have a chance:

Canned Insects and other Invertebrates – An Important New Food for Pet Reptiles and Amphibians

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

Providing a Balanced Diet to Reptile and Amphibian Pets – approaches to consider

Terrestrial Isopods (Sowbugs, Pillbugs, Potato Bugs) As Food for Captive Reptiles and Amphibians

The Marine Toad, Bufo marinus (recently re-classified as Rhinella marina) in Nature and Captivity – Part I, Natural History

My Animal Collection: How a Herpetologist Keeps American Toads, Bufo (Anaxyrus) americanus and Related Species, Part I

American Toad Setup

Today’s article is the second in a series concerning animals in my own collection.  For additional information concerning this line of articles, please see My Animal Collection: How a Herpetologist Keeps Barking Treefrogs (Hyla gratiosa) and Gray Treefrogs (Hyla versicolor).

Note: the following information is also largely applicable to other toads that commonly appear in the pet trade, i.e. the Great Plains toad, B. cognatus, the Gulf Coast toad, B. valliceps, the southern toad, B. terrestris, Woodhouse’s toad, B. woodhousei and the Texas toad, B. speciosus.  Fowler’s toads and the various Spadefoot toads prefer arid substrates…I’ll cover the care of both in the future.

Most North American toads in the Genus Bufo have been recently reclassified within the Genus Anaxyrus, but not all herpetologists agree on this point.

An Ideal Terrarium Pet

As with many of the animals I favor, American toads have much to offer the hobbyist but are not as popular as some of their more colorful relatives (actually, they vary greatly in color – I have run across yellow, reddish and nearly black specimens in the field).

Perhaps because they are so well- protected by virulent skin toxins, American toads are calm and confiding in captivity.  They usually take on diurnal habits, and even wild caught adults will feed from the hand in short order.  Pardon the stretch, but their behavior brings to mind that of the striped skunks I have kept.  Skunks seem to know that they are “untouchable”, and hence are very approachable (even in the wild)…toads are much like that, at least in my mind!

They are also quite intelligent and responsive – please see my article entitled “Amphibian Learning Abilities – the Southern Toad, Bufo (Anaxyrus) terrestris and Bumblebee Mimicsfor further details.

Designing the Terrarium

I currently keep 2 yearling American toads in a Tom Aquarium Jumbo PLA-House Plastic Terrarium.  This terrarium’s ventilation ports assure adequate air exchange (despite favoring moist habitats, toads and other amphibians fare poorly in stagnant air) yet are small enough to prevent small feeder insects from escaping.  This set-up is dismantled and cleaned weekly – the terrarium’s light weight simplifies this chore.

Substrate

The substrate pictured in the photo is R-Zilla Compressed Frog MossAmerican toads prefer a drier environment than do most frogs, so I use only ½ to ¾ of the amount of water called for in the instructions when preparing the moss (the moss is packaged dry, and must be reconstituted).  Hagen Exo-Terra Plume Moss and Zoo Med Terrarium Moss are also good choices for toads and other amphibians.

In this terrarium, the substrate is rinsed or spot-cleaned once mid-week and replaced weekly.  As with most amphibian terrariums, I use only hot water to clean, with bleach or table salt added when something stronger is called for.

Water

The terrarium is sprayed once daily with de-chlorinated water.The toads also frequently soak in their water bowl…just bear in mind that they are poor swimmers, so provide an easily-exited container for their pool.

Terrarium Decorations

I set up the terrarium in manner that encourages easy visibility and feeding- time interactions.  This is not always possible with amphibian pets, of course, as secretive species will languish and die if unable to hide.  American toads take to it readily however, and so observations, feeding and cleaning are much simplified.  In this terrarium the toads have become quite tame – noticing when I enter the room hopping forward in anticipation of a meal.

I provide a Zoo Med Turtle Hut or a Cork Bark Hollow as a retreat, but the toads are more often to be found on top of it, scanning the moss for insects or, it seems, watching the room in general.

Light

The PLA-House Hood Light fits right onto the terrarium’s lid, and is useful for providing additional illumination without excess heat.

In planted terrariums, a Reptisun 2.0 Florescent Bulb will provide sufficient light for plants without exposing the toads to harmful levels of UVB – most amphibians have UVB “filters” in their skin, and actively avoid the sun.

Click: My Animal Collection: How a Herpetologist Keeps American Toads, Bufo (Anaxyrus) americanus and Related Species, Part II to read the rest of this article.

 

Ant Mimicry in the Giant Spiny Stick Insect (Macleay’s Spectre), Extatosoma tiaratum: An Unbelievable Survival Strategy

 

Today I’ll introduce a member of a group of insects that have long fascinated me – the stick insects, or walking sticks. Several of the over 2,700 described species are well established in captivity, especially among European hobbyists. They are growing in popularity here in the USA also, most commonly, I’ve noticed, among reptile and amphibian keepers. (Note: laws governing the keeping of insects vary from country to country and state to state; please check those applicable to you before purchasing insect pets). Giant Spiny Walking Stick

Ants as Babysitters

Today’s insect hails from Australia and New Guinea (as do most truly bizarre creatures!). I’ll cover the husbandry of the giant spiny stick insect in the future…for now I’d like to provide you with a look at its most incredible reproductive strategy.

Female giant spiny stick insects lay approximately 12 eggs at a time, and may produce up to 1,000 or more during their lives. They fall to the ground after being quite forcibly ejected by the cloaca.

The eggs resemble seeds and are tipped with a structure known as a capitulum. The captiulum’s collar is a favored food of ants of the genus Leptomyrmex. The ants carry the eggs into their nest, where the collar is eaten. The stick insect’s eggs are then discarded in the ant colony’s underground rubbish pile, where, protected from predators and the fires that regularly ravage the forests above, they develop.

Tricking the Ants

The walking stick nymphs mimic Leptomyrmex ants in color (black body, red head) and move about in a rapid, frantic manner as do the ants (adult stick insects are slow moving). They also curl their abdomens up over the body, in the manner of their ant hosts.

Upon leaving the ant nest the stick insects moult, assume the adult body form and coloration, and climb into trees to live. All walking sticks undergo incomplete, or hemimetabolous, metamorphosis – there is no pupae stage.

A Variable Path to Reproduction

This species may reproduce either sexually or by parthenogenesis. Eggs produced via mating hatch in approximately 4 months, while those produced via parthenogenesis may take 9 months or more to hatch.

Strange, even for an insect, don’t you think? I’m always interested to hear about unique survival strategies…please write in with your own favorites and I’ll share them in future articles.

You can read more about this and related stick insects at:

http://www.novelguide.com/a/discover/grze_03/grze_03_00194.html#Macleays_spectre

Image referenced from Wikipedia and originally posted by Stephan M. Hohne

http://en.wikipedia.org/wiki/Image:Extatosoma_tiaratum_114.jpg

Keeping Snakes in Naturalistic Terrariums

 

Natural Snake ExhibitIn 1969, Carl Kauffeld introduced a generation of budding herpetologists to snake-keeping with his wonderful classic Snakes: The Keeper and the Kept. In it he laid out the basic principals that had yielded him decades of success while curator of the well-known reptile collection at New York City’s Staten Island Zoo – simple, easily cleaned enclosures that provide a secure retreat and basking site. Such became, and largely remains, the standard approach to snake-keeping in the USA.

European zookeepers and hobbyists, by contrast, favor planted, naturalistic exhibits, and it was to these I gravitated. Although not nearly as easy to maintain as bare cages, for certain snakes I find complex terrariums to be a very worthwhile undertaking.

Possible Pitfalls
Cleanliness and the control of excess moisture and parasites can be major concerns…one of my first mistakes involved keeping a banded watersnake in a filtered aqua-terrarium. The animal was not able to dry off sufficiently, and developed blisters. Then Bronx Zoo curator Wayne King (imagine the curator of a major reptile department personally answering a 10 year-old’s letter today!) suggested some changes, and the snake recovered.

Candidates for Naturalistic Terrariums
In my experience, small species are the best to start with when attempting naturalistic snake terrariums. Such animals are easier on plants and decorations, and secretive snakes really do seem much more “at home” in captive habitats that offer numerous burrowing and hiding opportunities.

DeKay’s (brown) snakes do wonderfully in forest-themed tanks, and often breed readily. Other favorites of mine include smooth and keeled green, garter, ribbon, ring-necked, red-bellied and tentacled snakes.

Larger species are more easily maintained in simple set-ups, especially if space is limited, but there are still some possibilities. Watersnakes will bask on branches over-hanging a pool, just as in the wild, and corn and various ratsnakes will utilize just about every bit of cage furniture provided. Shy or high-strung arboreal species, such as green tree pythons and Cook’s tree boas, also favor well-planted terrariums perched with natural tree branches.

The Staten Island Zoo’s Reptile House Today
In an odd twist of fate, I recently had the opportunity to help plan the complete renovation of Mr. Kauffeld’s amazing building. Having grown up near to and in awe of the man and the institution, it was quite an odd feeling, to say the least. I set up naturalistic exhibits for nearly all of the snakes, but a re-creation of Mr. Kauffeld’s office holds a number of terrariums set up as he would have wanted. I sincerely hope he approves! Please visit if you have a chance…I would greatly appreciate your comments.

Please Note: some of the photos accompanying this article feature venomous snakes. These are presented as illustrations of terrarium set-ups that might be useful for animals from similar habitats, not as an inducement to keep venomous snakes at home. Venomous snakes should never, under any circumstances, be held in captivity outside of a professionally managed scientific institution.

 

Many zoos use complex exhibits as a means of providing behavioral stimulation to snakes. Read more at:
http://reptilebehavior.com/riverbankspaper.htm

Breeding a Skin-Brooding Amphibian: the Surinam Toad (Pipa pipa)

Surinam ToadThe bizarre Surinam toad needs little introduction to amphibian enthusiasts…their unique strategy of brooding the eggs below the skin of the female’s back has rendered the species quite well-known. Yet, when I received a group of adults in 1986, I found that little had been published on their husbandry, and the last recorded captive breeding seemed to have occurred in the 1950’s.

Courtship and Fertilization of the Eggs
One female was in breeding condition, as evidenced by the circular, swollen ring about her cloaca and the dark brood patch on her back. Several males were giving forth their metallic, clicking breeding calls, so I chose the most robust of the group and placed him with the female.

Surinam toads swim in a series of circular loops, from the bottom to the top of the aquarium, when in amplexus, and will rarely be successful in fertilizing the eggs unless provided with a tank of at least 48 inches in depth. As the pair reaches the top of their loop, the female lays an egg, which is (on the next loop) fertilized and manipulated by the male onto her back’s spongy brood patch.

My Observations of Amplexus and Birth
Amplexus in the frogs I observed lasted for nearly 3 days, which I have subsequently found is the norm. The pair “shivered” in unison on many occasions, but I was not able to see the “bobbing” motions described by others. The photo accompanying this article shows what might be the first captive breeding (this while I was working at the Bronx Zoo) in many years. Within 24 hours of this photo, the skin on the female’s back swelled and completely covered the eggs.

After egg-laying, I removed the male. The female fed as usual. I did not offer blackworms, as these voracious little beasts burrowed into the soft skin of her brood patch at one point…talk about a horrid sight (I was able to wash them away easily)!

The young began to pop their heads out (the sight of 74 pointed little heads protruding from their mother’s back was yet another vision not for the squeamish!) in 100 days, and swam off on their own within a day or so. They averaged ½ to ¾ inches long, and fed readily upon chopped blackworms, brine shrimp and guppy fry. Sexual maturity was reached in 3 years.

Amazing Healing Abilities
The females back appeared “healed” within 24 hours of giving birth, but remained roughened in appearance for several weeks. Amphibians are increasingly being found to produce compounds of great medicinal value…I wouldn’t be surprised if the incredible skin trauma undergone by female Surinam toads is somehow tempered by a chemical that could be of use to people.

A wonderful video of baby Surinam toads emerging from their mother’s back is posted below:

Baby Surinam Toads emerging from their mother’s back

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