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Albino and Leucistic American Bullfrogs, Rana catesbeiana (Lithobates catesbeianus): a Request for Your Input


Albino BullfrogsAlbino and leucistic American bullfrogs are becoming quite popular in the pet trade.  The two females that I’m holding in the accompanying photograph are approximately 1 year old, and were received as tadpoles.  The other photograph shows two others in an exhibit I prepared for the Maritime Aquarium in Connecticut (note the pumpkinseed sunfish…bullfrogs usually do quite well with predatory fish).

Basking Platforms

Albino Bullfrogs in ExhibitThe frogs in the exhibit photo are resting upon an R-Zilla Basking Platform.  I use these extensively, both at home and in the zoo/aquarium exhibits that I design.  The platforms are very realistic in appearance, especially when surrounded by real or artificial plants and with a light covering of algae.  They are equipped with a stick built into the surface – you can wedge a bit of R-Zilla Beaked Moss below this for extra effect.  I also favor the Zoo Med Turtle Dock.  One end of this platform slopes below the water, providing easy access to metamorphosing frogs, newts and other creatures that might need a bit of help exiting the water.  I’ve also used this model for a spotted turtle that lost his rear legs in an accident…the gentle slope allows him to easily climb on board.

In most situations, I prefer suspended platforms to rock piles, as the former leave the water below clear for swimming.  Cork Bark works well also, but floats freely or must be cut to fit the tank and wedged into place.

An Un-cooked Chicken!

Most visitors to the aquarium remark favorably upon the albinos, which live in an exhibit with normally colored bullfrogs.  I did, however, overhear one gentleman respond to his companion’s “Aren’t they interesting?” with a definitive “They look like un-cooked chickens”!

Unusual Physical Traits (in addition to their color, or lack thereof!)

Albino bullfrogs behave in all respects as do normally-colored individuals, and like them vary greatly in their dispositions.  The two in my collection are incredibly shy, while a male on exhibit frequently calls during the day, in full view of the visitors.  However, I noticed that mine lacked the solid “feel” that I associate with bullfrogs, and seem not to have very good muscle tone.  They move slowly, and “slide” more than jump from basking sites when disturbed.  Those at the aquarium, and in the possession of a colleague in Louisiana, exhibit similar characteristics.

All were raised on well-proven bullfrog tadpole favorites (kale, algae, algae tabs, Tetramin fish flakes and bits of fish) and since metamorphosis have been fed a varied, high calcium diet that has always yielded robust frogs in the past – crayfish, minnows, earthworms, well-fed crickets, roaches and wild-caught cicadas, grasshoppers and other insects.


Field notes on albino bullfrog tadpoles in the wild are detailed in an article posted at:


A visitor to the aquarium exhibit mentioned in this article has posted a video about it, see below

“Begging Behavior” Among Tadpoles of the Strawberry Poison Frog, Oophaga (formerly Dendrobates) pumilio

Strawberry Poison FrogThe success that hobbyists have had in establishing breeding populations of so many species of poison frogs is truly astonishing, and has served a greater purpose in removing the financial incentive to collect them from the wild.

Unfortunately, the extraordinary parental care supplied by many poison frogs is difficult to observe in captivity, and the most effective way of rearing the tadpoles is to remove them from their parents’ terrarium. I was most fortunate to have had the opportunity to observe the breeding behavior of wild strawberry poison frogs in Tortuguero, Costa Rica, and in a large zoo exhibit.

Finding and Feeding the Tadpoles
Strawberry poison frog tadpoles, which are moved by the female frog to individual water-filled bromeliad stems, exhibit what has been termed “begging behavior” when their mother visits their pools. When the female lowers her vent into the water, the tadpole moves against her, stiffens, and vibrates. This stimulates the female to release 1-5 unfertilized eggs, which comprise the tadpole’s sole diet.

She visits and feeds each of her offspring, every other day or so, for the 43-52 days that they remain in the tadpole stage…no wonder these tiny moms eat so much! When one considers the complexity of the frog’s rainforest environment, especially as compared to the size of the frog, the female’s ability to locate each tadpole borders on the unbelievable.

Additional Behaviors
Outstanding herpetologist Elke Zimmermann (in “Breeding Terrarium Animals, 1986. TFH: Neptune City, NJ) has even observed females to dip their heads into bromeliad pools before laying, and notes that disturbances from other than the mother frog sends the tadpole into retreat. Field research in Panama indicates that female strawberry poison frogs consistently avoid feeding other than their own progeny.

I was able to observe parental care only in huge exhibits and the wild, but please write in if you would like to try at home…it’s well worth the effort.

We now know that Chirixalus eiffingeri, a treefrog endemic to Taiwan, also communicates with and feeds its tadpoles. The abstract of an article documenting this behavior is posted at:

The Natural History and Captive Husbandry of the Taiwan Beauty Snake or Chinese Ratsnake, Orthriophis (formerly “Elaphe”) taeniurus friesei

Taiwan Beauty SnakeI’ve never quite understood why the aptly named Taiwan beauty snake did not soar in popularity as soon as it entered the pet trade. I was captivated by them from the moment I began looking after a group at the Bronx Zoo some 15 years ago, and added the species to the Staten Island Zoo’s collection when working on the reptile house renovation there. Today, these arboreal constrictors are beginning to receive some attention from hobbyists, and captive born young are frequently available.


Taiwan beauty snakes are placed within the family Colubridae, and until recently were classified in the genus Elaphe, along with the corn, black rat and similar North American snakes that they superficially resemble. Eight to nine subspecies have been identified, but interbreeding where their ranges overlap complicates taxonomy. The group is often loosely referred to as the Asian ratsnakes.

Physical Description
The background color of these gorgeous snakes is yellowish tan/brown to olive, and a pair of joined black spots and smaller blotches mark the back. Along the last third of the body the color pattern abruptly changes – from here the snake is boldly marked with a band of yellow and 2 black stripes. Smaller blotches cross these, and a black stripe extends from the eye to the mouth’s corner. The ventral surface is creamy-white speckled with black.

The tail is highly prehensile, allowing for long strikes at fast-moving, arboreal prey.

This largest member of its genus averages 5-6 feet long, but occasionally approaches 9 feet in length.

This subspecies is native to the island of Taiwan, but is possibly introduced to mainland China. Related subspecies range throughout much of India, China, Southeast Asia and Japan’s Ryukyu Islands.

This snake and its relatives, most of which are quite colorful, are sometimes kept in rural homes and barns for their rodent-catching abilities. This has resulted in range expansions for a number of beauty snake subspecies. As individuals are highly variable in appearance, and the subspecies readily interbreed, the taxonomy of the genus is unclear.

Taiwan beauty snakes are quite adaptable, being found in forests, open woodlands, overgrown fields, swamps and suburban areas. If unmolested they will take up residence in barns, rural homes and agricultural fields. All beauty snakes are highly arboreal but will descend to the ground to hunt.

Status in the Wild
The wild status is largely unstudied, but it is known that the Taiwan beauty snake is hunted for the food, skin, pet and medicinal trade. However, it adapts well and may even benefit from some human presence, frequenting farms, trash dumps and abandoned buildings in search of rodents. Some range expansion has likely occurred via people who transport this snake (and related subspecies) from place to place as a rodent control measure.

Squirrels, rats, mice, bats and other small mammals, birds and their eggs; hatchlings feed largely upon treefrogs and lizards. Prey is overcome by constriction.

The 6-10 eggs are laid in May-June, but other than that reproduction in the wild is not well documented. Please see below for captive breeding information.

The Taiwan beauty snake’s threat display is very impressive – it compresses and inflates the first third of its body and rears up in an “S” shaped coil while facing the enemy and striking repeatedly.

Please check back Monday for information on the captive husbandry requirements of Beauty Snakes.

Image referenced from Wikipedia. First published by MSP. http://en.wikipedia.org/wiki/Image:Beautysnake.jpg

Flour Beetles (Confused or Rice Flour beetles, Tribolium confusum and Red Flour Beetles, T. castaneum) – a valuable food for small amphibians and reptiles

Flour beetles of various types are serious pests in grain product storage facilities, and those discussed here are worldwide in distribution.  However, the traits that make them successful invaders also render them easy to culture in captivity.

The larvae, or grubs, of the beetles offer an easy way to add nutritional variety to the diets of tiny reptiles and amphibians, most of which must subsist on only a few food items in captivity.  The adult beetles release an irritating gas when disturbed, but are none-the-less consumed by some reptiles and amphibians.

Obtaining Flour Beetles
I was first introduced to flour beetles some 20 years ago by Bob Holland, an amphibian expert who was setting longevity records with poison frogs long before most zoos kept any at all.  In those days, we collected our founding stock by searching through old containers of dry dog food and cereal.  Today, cultures of confused and red flour beetles are available from private breeders and biological supply houses.

Culturing Flour Beetles
Although most beetle breeders advise keeping the animals in a mix of flour and yeast, Bob’s method of rearing them in dog biscuits has worked very well for me.  The problem with a flour mix is that the medium must be sifted through a fine net each time larvae are needed, which leaves one with unwanted beetles, pupae and shed skins.

Dog biscuits provide all the food, moisture and shelter needed by the beetles (be sure to crack open the biscuits to give the beetles easy access to the interior).  When larvae are needed, I simply tap a biscuit over a Petri dish.  The larvae can also be concentrated by tapping several biscuits over a separate container, into which only 1 biscuit has been placed.  All the grubs will eventually gravitate to the 1 biscuit, allowing you to collect many in a short time.

Using Flour Beetles
The adult beetles live for approximately 1 year, with the period from egg to adult being 4-6 weeks, depending upon temperature.  The larvae are 3/16th of an inch long when fully grown – an ideal size for poison frogs, harlequin frogs and newly morphed froglets of small species such as spring peepers.  I have also fed them to red-backed and red salamanders, the larvae of various newts and to small granite night lizards.

An article concerning the natural history and pest status of flour beetles is posted at:

Research Update – Perret’s Night Frog (Astylosternus perreti) Defends Itself with Skin-Sheathed Claws

Harvard biologist David Blachurn knew he was onto something unusual when a benign-looking frog he was examining in Cameroon, West Africa kicked out and left him with a bleeding cut.  Unusual indeed – an article  (23 August 2008) in Biology Letters describes the hidden claws of Perret’s night frog as the only vertebrate claws known to break through the skin in order to become functional.  Some, or possibly all, of the other 10 frogs within the genus Astylosternus are also equipped with skin-covered claws on their toes (the fingers are clawless).

Suriname Toad with Eggs on BackThe frog’s sharp, curved claw is actually the last bone of the toe, and pierces the toe’s skin when a specific tendon is flexed.  It is assumed that the claw retracts after use and the skin heals, but further study is needed.  Other amphibians that experience “self-inflicted” wounds include the Surinam toads, Pipa spp., whose young push through the skin of the female’s back when ready to swim off on their own and the ribbed newt, Pleurodeles waltl.  The ribs of this newt pierce the skin of the back, carrying toxins with them, when the animal is threatened.

Despite the massive trauma caused by the emergence of 80+ fully formed little frogs, the skin of breeding Surinam toads (P. pipa) under my care appeared well-healed within 24 hours.  I’m sure there are some compounds that may be of medical use to people hidden in the body chemistry of this and other amphibian species.

Of course, people living within the habitat of Perret’s night frog have long known of its odd defense and even utilize specially-constructed spears when hunting it, to avoid being injured.

The only other frogs known to have claws are members of the family Pipidae – the various African clawed and dwarf African clawed frogs.  I have observed both putting their claws, which are always exposed, to interesting uses (more to come in future articles).

You can read more about this frog and related species at:

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