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

In the late 1980’s I was privileged to breed the now rarely-seen Smoky Jungle Frog, Leptodactylus pentadactylus, a large (8 inch snout-vent length) Latin American native that constructs foam nests on land.  In the wild, rain washes the tadpoles into a nearby pool, where they develop in normal frog fashion…following suit, I successfully reared a number in water.  I subsequently learned that some frog nests are placed far from the water’s edge, and that the tadpoles therein develop entirely on land.  But what did they eat…the nest’s foam, perhaps?  There were theories, but no answers.

Subterranean Frog Nests

Herpetologists working with the closely related Mountain Chicken Frog (L. fallax) at the Durrell Wildlife Conservation Trust have recently solved the riddle – and captured the bizarre event on film.  Mountain Chicken Frogs, highly endangered and limited to Dominica, St. Kits, Martinique and a few neighboring islands, lay their eggs in foam nests underground, and the tadpoles develop without ever seeing water.

The startling footage taken by the researchers, shows scores of tadpoles gorging on unfertilized eggs produced by their mother.  In sharp contrast to certain more “civilized” oophagus (egg-eating) poison frog tadpoles, the chicken frog larvae do not wait until the eggs are actually deposited, but rather swarm about the female’s cloaca, eating ravenously as the eggs emerge.  It’s quite a scene!

A Taxing Time for Mom

Subsequent research has revealed that the harried mother uses her rear legs in an attempt to re-distribute the unusual food, and perhaps to give all of her gluttonous progeny a chance to feed.  She has her work cut out for her…the 25 to 50 tadpoles that she rears require 10,000 to 25,000 unfertilized eggs to see them through to metamorphosis!

Further Reading

Frogs break all the rules when it comes to reproductive behavior, constantly surprising even the most seasoned herpetologists.  To read about tadpoles that “petition” their mother for food, please see my article Begging Behavior Among Strawberry Poison Frog Tadpoles.

Smoky Jungle Frog image referenced from wikipedia and originally posted by Ltshears
Leptodactylus fallax image referenced from wikipedia and originally posted by TimVickers

Most turtles become quite responsive to their owners (especially near feeding time!), and a great many show impressive abilities to learn and adjust to new situations. In my experience, however, few approach the wood turtle (Glyptemys insculpta, formerly Clemmys,) in these areas.

Testing Turtles

Herpetologists and experienced turtle enthusiasts consider the wood turtle to be among the most intelligent of the turtles – in lab tests, they consistently scoring higher than other species on maze and reward-association tests. In my experience, captives exhibit a degree of curiosity and problem-solving abilities not evident in other turtles.

“Thinking” before Acting?

While all turtles soon come to associate their owners with food, wood turtles rarely rush about “begging” each time one approaches their enclosure, as do other species. Instead, they most often look intently at their benefactor – deciding, it seems, if it would be “worthwhile to beg”. A group I worked with would always regard me carefully as I passed, but only scrambled for position if I carried their food trays.

These turtles were housed in a 6-foot-long cattle trough, tilted on one end to form a pool. When I drained the enclosure, they invariably gathered near the drain to snatch leftover food carried there. Turtles that missed a morsel of food would peer down the drain for some time, often changing angles to get a better view. Again, they seemed to “consider” the situation – not wasting effort trying to retrieve a food item that was unreachable.

Turtles Tricking Earthworms

Earthworms, a favorite food, are lured to the surface by stomping the front feet and the plastron against the ground. It is believed that earthworms interpret the vibrations as rain, or that the vibrations stress the worms and force them upward – hammering a piece of wood into the ground often has the same result. This is the only turtle known to employ such a technique.

While this behavior may be instinctive and does not necessarily indicate intelligence, one has to wonder why other turtles do not do so. It would be interesting to discover if all wood turtles do this, or if a degree of learning is indeed involved.

I’ll cover wood turtle care in the future. Please write in with your questions and comments. Thanks, until next time, Frank Indiviglio.

Further Reading

An interesting field report on how habitat development affect wood turtles is posted at http://www.woodturtle.com/Saumure%20and%20Bider%201998.pdf.

To read more about reptile intelligence, please see my article Learning: Observations of Zoo Animals (Lizards).

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.

Turtles and tortoises are the most popular of all reptilian pets – even “non-herpers” like them – and this is reflected by the many websites devoted to Chelonian-related matters. Following are some that I have found to be especially valuable. This list is by no means exhaustive…I’ll cover others in future articles.

The New York Turtle and Tortoise Society

I’ve worked with the dedicated folks at NYTTS for many years, and they have been kind enough to feature my articles on their website. More important (infinitely more!) than my connection to NYTTS is their long standing relationship with legendary turtle biologist Peter Pritchard, who often speaks at the group’s day-long annual seminars. Rhom Whittaker, Mike Klemens, Roger Wood, Indraneil Das and numerous other notables have also participated in NYTTS sponsored programs.

NYTTS provides quality husbandry information and also gets involved in the hands-on work upon which the survival of so many turtle species depends. They have long provided support to Southeast Asian students studying turtle biology here in the USA and to the fine work of the Wetlands Institute and have helped in large scale rescues of confiscated turtles.

NYTTS conservation and trade issues expert Alan Salzberg publishes Herp Digest, a wonderful resource and the only free electronic herp conservation and natural history newsletter.

Tortoise Trust

Tortoise Trust is one of the reptile-world’s most highly-respected sources of information on turtle and tortoise husbandry, conservation and natural history. Noted author and herpetologist Andy Highfield directs the organization, which is utilized by professionals and hobbyists alike.

Tortoise Trust is unique among turtle interest groups in the range of activities it sponsors – courses, field trips, political action, research efforts – and in the numerous top notch publications it has generated (in addition to online material).

Turtles of the World

It’s difficult to believe that a resource of this caliber is available without charge on the inter net. An updated version of Ernst and Barbour’s classic book Turtles of the World, this publication provides detailed accounts and photos of the 288 species of turtle and tortoise described at the time of publication. A “must read” for serious turtle enthusiasts.

Turtle Homes

Operated by volunteers throughout the USA, the UK and Canada, and with connections to similar organizations in Asia and elsewhere, Turtle Homes members seek to place un-releasable turtles and tortoises with people or organizations that can properly tend to their husbandry and veterinary needs. They also post accurate care sheets, answer questions and direct site visitors to appropriate sources of information.

The California Turtle and Tortoise Club

The husbandry articles drawn from CTTC’s magazine, Tortuga Gazette, and posted on the group’s website, offer Chelonian enthusiasts some of the best information available on the inter net. The printed version of the Tortuga Gazette, published since 1965, is a well-written, invaluable resource to hobbyists and herpetologists alike.

The group is also actively involved in conservation efforts and supportive of turtle-friendly legislation, and offers site users a number of ways to participate in such. In addition to dozens of informative articles, one may also find photographs and even recordings of tortoise vocalizations on this most useful web site.

Please see Part I of this article for a description of UVA light, information about its importance to reptiles and amphibians and its role in their captive husbandry.

Light and Heat

In addition to promoting natural behavior and improving the appetites of many captive reptiles and amphibians, ( Part I), the light emitted by UVA bulbs will also accentuate your pets’ natural colors.

The models listed below are incandescent, and therefore provide heat and encourage basking.  When placed in close proximity to florescent UVB bulbs (which emit little heat), UVA bulbs can help assure that your pets receive the full spectrum of essential light rays.

Light Cycle

The length of the UVA light cycle provided is critical, especially for those creatures that are native to areas subjected to seasonal changes in sunlight intensity and duration.  Ideally, you should study the natural habits and ranges of the animals in your collection, and endeavor to provide them with an appropriate light cycle.

Suggested UVA-Emitting Bulbs (Lamps)

Zoo Med manufactures a number of useful UVA bulbs. Repti-Halogen Bulbs are available in 50-150 watt sizes.  Repti-Basking Spotlights offer a narrow, tight beam, and range in size from 25-150 watts.

Zoo Med Turtle Tuff Halogen Bulbs  are water-resistant, and so can stand up to the splashing that is so common around aquatic turtle basking areas without breaking.  They have an average life of 2,500 hours.

Other high quality UVA bulbs include the Hagen Sun Glo Daylight Halogen and R-Zilla’s Spot Day White Bulbs and Incandescent Day White Bulbs.