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

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

Captive Husbandry
Space and Physical Requirements
Taiwan beauty snakes are quite active and require a larger cage than other similarly-sized snakes – they do not do well when cramped. A cage with sufficient height for climbing is a must – both for your pleasure in observing the animal, and for the snake’s well-being. A cage with the dimensions 3’(l) x 3’(w) x 5’(h) would be the minimum required by a 5 foot long individual.

The cage should be well perched with stout branches. Taiwan beauty snakes will also utilize vines, moving about them with a speed that leaves little doubt as to their abilities to capture squirrels, birds and other elusive prey. Hagen Bendable Vines interspersed among the branches will allow your pet to show off its natural behaviors to their best effect.

Taiwan beauty snake prefer an arboreal hideaway, and will readily take advantage of a forked branch hidden behind a screen of plants (Hagen Large Hanging Terrarium Plants are ideal). Particularly shy individuals will appreciate a piece of rolled cork bark wedged among the branches.

Light, Heat, Humidity
This species does not require a source of UVB light, but there is increasing evidence that UVA light is important in stimulating natural behavior and possibly in maintaining over-all good health. I suggest equipping your snake’s terrarium with a Coralife Reptile Bright Spotlight, which will supply both heat and UVA radiation.

A temperature of 80 F at the basking site will suffice – Taiwan beauty snakes do not seem to seek out the higher temperatures favored by some other tropical species. The ambient air temperature should fall 74 and 78 F.

Members of this genus favor slightly humid environments, but will suffer fungal and other skin disorders if not able to dry out as well. A light misting once or twice each day should suffice.

One Taiwan beauty snake that I kept invariably came to drink from the hose each morning when I misted her cage, but most will prefer a water bowl. The bowl should be large enough for soaking, as this species is prone to shedding difficulties if kept too dry. Be sure to spray the cage a bit more frequently at shedding time as well.

For arboreal snakes favoring humid environments, I use a substrate that holds moisture for awhile, but which dries out completely within a few hours after being misted. A mix of Keeper’s Choice Hardwood Bedding and Hagen Forest Bark Reptile Bedding works very well in this regard.

Feeding
Many arboreal snakes, such as the red-tailed ratsnake (Gonyosoma oxycephala), show a strong preference for feeding on birds, but I have not seen this with Taiwan beauty snakes. They do fine on a diet composed of mice and small rats.

Captive Longevity
Captives have lived in excess of 15 years.

Handling and Enrichment
Some individuals do adjust well to gentle handling, but in general this species is far better suited as an exhibit animal. Even well-habituated animals must be handled frequently, and starting from a young age, if they are to remain tractable. Taiwan beauty snakes do not take well to being grabbed and restrained, which complicate removal from the complex, branch-filled environments that suit them best.

Their high activity levels suit them well as subjects of observation, and in a large, naturalistic terrarium these snakes will provide you with fascinating glimpses into their lives. They appear much more alert than many species, and will investigate unusual movements around their cage. You can capitalize on this propensity by “scenting” their cage with novel odors – i.e. a snake or lizard shed, an egg – so that you can observe their reactions (in zoo circles, this is long-known practice is now termed “enrichment” and is currently very much in vogue).

Breeding
Taiwan beauty snakes may breed spontaneously, but consistent results have been obtained following a brumation (cooling-off) period of 3 months or so at 65-68 F. Most breeders chill their snakes between December and March, but this time period is likely not set in stone. Mating usually occurs within a month after the snakes are returned to optimal temperatures, with 6-10 eggs being deposited 40-60 days thereafter.

The eggs hatch in 55-62 days when incubated at 80-84 F and 95% humidity. The hatchlings average 12-16 inches long, and shed within their first 2 weeks. In contrast to many arboreal species, they do not prefer or need lizards or treefrogs, and will accept pink mice readily. Captives (this may vary in the wild) reach sexual maturity at approximately 18 months of age and 4.5 – 5 feet in length.

You can read more about the natural history and taxonomy of Asian ratsnakes at:
http://www.tigr.org/reptiles/species.php?genus=Orthriophis&species=taeniurus

An article to be published later this month (Zootaxa; August, 2008) will announce that a newly described Thread Snake from the Caribbean island of Barbados is the smallest of the world’s 3,100+ snake species.  The Barbados Thread Snake grows to a mere 4 inches in length, is no thicker than a strand of spaghetti, and can coil comfortably atop a quarter.  It subsists largely upon ant and termite larvae, and may be threatened by habitat loss.  A relatively large hatchling – ½ of the adult size – emerges from the single egg laid by the female (perhaps there is no prey species tiny enough to support a larger brood of smaller-sized young).

A related snake, nearly as tiny, has been discovered on nearby St. Lucia.  Two snakes within the genus dwell in the southwestern USA – the other 103 species are found in Mexico, Central and South America, the Caribbean, Africa, India and Pakistan.

The Penn State biologist who discovered the snake, Blair Hedges, seems to have a quite a flair for his work – he and his colleagues have named 65 new amphibian and reptile species on Caribbean islands, including the world’s smallest lizard and smallest frog.

Islands and other isolated habitats are often home to the largest (Komodo Dragons, Aldabra and Galapagos Tortoises) and smallest animals within a group.  Islands are difficult for many animals to reach, so those that do arrive often evolve into a variety of forms (and, eventually, species) to fill the many empty niches (specialized roles within a habitat) – in fact, Darwin’s theory of evolution was sparked by his observations of this process among finches on the Galapagos Islands.  Caribbean Thread Snakes, Australia’s monitor lizards and the African Rift Lake cichlids are likely examples of this phenomenon.

You can read more about other species of Thread Snakes at:
http://www.tigr.org/reptiles/families/Leptotyphlopidae.html

Introduction
The snake world is full of species that “break the mold” – none more so than a Southeast Asian import that sometimes appears in the trade, the tentacled snake.

The care of this snake differs greatly from that of all others, and I’ll devote a full article to it shortly.  For now, I’d like to introduce the species to those of you who may be looking for a new challenge.

The Tentacles

The tentacled snake is unique among snakes in its possession of 2 fleshy tentacles (adjacent to the nostrils), the function of which is still unknown.  It has been suggested that they have a sensory function, detect water movement, lure prey or break up the outline of the head.

Unique Adaptations
This inactive snake resembles a water-logged root, an effect that is heightened by its color, rigid posture, habit of remaining anchored to sunken branches, and the covering of algae that grows on the scales.  It rarely swims, waiting instead for fish to approach closely before striking.

Completely aquatic, this species lacks the broad ventral scales of terrestrial snakes and is helpless on land.  When disturbed, it becomes rigid and immobile (in Thailand, it is known as the “Board-like Snake”).  The nostrils can be sealed to exclude water, and it may remain submerged for 30 minutes before surfacing to breathe.  Tentacled snakes are thought to aestivate by burrowing into the mud during droughts.

Tentacled snakes produce mild venom that is effective against the fishes and tadpoles upon which they feed.  The venom has not been shown to be dangerous to humans – the two people I know of who have been bitten experienced mild swelling that disappeared within a few hours.

Unusual Relatives
The subfamily to which this species belongs, Homalopsinae, contains a number of aquatic snakes that frequent unique habitats and hunt in unusual ways.  For example, the white-banded mangrove snake, Fordonia leucobalia, hunts crabs on tidal mud flats in Southeast Asia and northern Australia.  It is quite effective at overcoming this unusual prey – utilizing constriction and crab-specific venom before finally tearing off the crab’s legs.  It may even employ its oddly blunted teeth to help crush its victims’ hard shells – the only snake known to use teeth in such a fashion.

Further information on tentacled snake natural history, as well as a picture, is posted at:
http://eobasileus.blogspot.com/2008/02/utterly-outrageous-tentacled-snake.html

Growing up near the Bronx Zoo, I became fascinated by giant snakes early on, as these magnificent creatures were always featured prominently in my favorite building, the Reptile House.  So it was with great anticipation that, after some years as a reptile keeper for the zoo, I set off for Venezuela to assist in field studies of the green anaconda, arguably the world’s largest snake.

Accounts of what I observed and learned during three visits to that country’s central llanos area (seasonally flooded grasslands) would fill several books.  I would like here to just give you some facts and photos – in the future, I will highlight some of my experiences in longer articles.

Despite long-standing legends to the contrary, (and, recently, a plethora of internet photos) there is only one reasonably reliable account of a snake measuring over 30 feet in length (I’ll cover the details of this and related stories in the future).  In fact, the Bronx Zoo offered a cash reward, established, as legend has it, by Theodore Roosevelt, for a living snake in excess of 30 feet.  That reward, now withdrawn, stood uncollected for nearly 100 years (I was involved in the last attempt to collect it – please look for details in the future).

The snake you see pictured here was the largest that I and my colleagues encountered.  It measured just over 17 feet long and weighed 215 pounds.  As you can see from the close-up of my hand on its head, she (all anacondas
of this size are females) put up a quite vigorous battle when captured – indeed, one of her teeth remains imbedded in my wrist till this day as a reminder!  A number of the 500+ green anacondas that were marked during the study were in the 15 to 16 foot range.

I was fortunate to come upon quite a few anacondas in the process of feeding upon a wide array of animals, including capybara, caiman, jacanas and other birds, turtles and, most unforgettably, a deer of 60 pounds in weight.  Please look for future articles on the details of these most fascinating encounters.

The Venezuelan llanos, especially in the dry season, offers a wildlife-viewing extravaganza that is difficult to put into words.  Encounters with crab-eating foxes, freshwater dolphins, giant anteaters, armadillos, electric eels, caiman, scarlet ibis and countless other creatures large and small are all but guaranteed.  Cougars, jaguars, giant otters, tamandua, tree boas, tegus and a host of others are also a real possibility.  I am planning to write an article for people who might like it explore (and “exploration” it is, in the true sense of the word) this area – please look for it in the future.

You can learn more about the field research project I described in this article at:

Anaconda Expert Wades Barefoot in Venzuela’s Swamps

Overview
The black rat snake and the related corn snake, E. guttata, were among the first to become firmly established in North American herptoculture, and remain pet trade staples. At least 11 species of the genus Elaphe are found throughout North and Central America.

The taxonomy of this genus is confusing due to a wide variation in the appearance of individuals of the same species, and to the fact that different species inter-breed where their ranges overlap. The black ratsnake was formerly known as E. obsoleta, but that name is now assigned to the Western ratsnake. Recently, genetic evidence has shown that many North American ratsnakes should actually be classified within the genus Pituophis, along with the bull, gopher and pine snakes.

Physical Description
Although usually a uniform black in color, with an off-white underside, some individuals show traces of dark gray blotches and stripes. Juveniles differ markedly from adults, being pale gray and strongly patterned in dark gray or brown. Hobbyists have developed a number of unique color morphs, including albino individuals, and frequently hybridize this snake with related species. Black ratsnakes average 3 – 5 ½ feet in length, with the record holder being a giant of 8 ½ feet recorded from Westchester County, NY by noted herpetologist Raymond Ditmars.

Black ratsnakes living from North Carolina through the Florida Keys vary greatly in appearance from northern specimens, being various shades of yellow and orange in color. Formerly classified as distinct subspecies, known as the Everglades’s ratsnake and yellow ratsnake (both popular in the pet trade), they are now considered to be local color variations of the black ratsnake.

Range and Habitat
Black ratsnakes occupy much of Eastern North America – from SW New England and S Ontario to the Florida Keys and from SW Wisconsin to Oklahoma and N Louisiana. Happily for NYC-based “herpers” such as I, they are still to be found within NYC limits (parks in the Bronx and Staten Island), and in suburban Long Island and Westchester. Quite adaptable as regards habitat, they utilize forests, fields, rocky hillsides, swamps and overgrown suburban lots. It is one of many snake species drawn to farms, stone walls, trash dumps and abandoned buildings in search of mice and rats. In some habitats, black ratsnakes are highly arboreal and shelter in tree hollows.

Status in the Wild
Population levels appear stable in most areas, although the species is listed as of “Special Concern” in Minnesota and elsewhere. It adjusts well to some human presence and, if left alone, may become common on farms and near refuse disposal areas. Large scale captive breeding has removed collection pressures from wild populations.

Diet
Black ratsnakes are powerful constrictors. They tend, as adults, to focus on mammalian prey such as squirrels, chipmunks, rabbits, bats, voles, deer mice, rice rats, small opossums and similar creatures, but also take birds and their eggs. Young snakes include lizards, frogs and large insects (i.e. cicadas) in their diet.

A colleague of mine observed 6 foot-long (yellow-phase) black ratsnake attempting to constrict a white-tailed deer fawn on St. Catherine’s Island, Georgia. The fawn, which might have set a new “snake swallowing record” had it been overcome, eventually escaped.

Reproduction
Mating occurs from March to May, with 6-30 eggs being laid 27-28 days thereafter. Second clutches, laid in August, have been reported in captive situations but not in the wild. The eggs are secreted in cavities below fallen trees and rocks, or within rotting logs and stumps. The young, 11 – 13 ½ inches in length, hatch in 47-85 days.

Miscellaneous
The black ratsnake frequently shares hibernation dens with rattlesnakes, copperheads and other species. In some parts of the country it is known as the “pilot blacksnake” or “rattlesnake pilot”, in the mistaken belief that it guides rattlesnakes to their winter retreats.

Black Ratsnakes as Pets

General
With their moderate size and even temperaments, black ratsnakes make excellent pets. They are hardy enough for beginning hobbyists, and yet are so interesting that even well- experienced keepers often reserve a place for 1 or 2 in their collections.

Space and Other Physical requirements
Black ratsnakes do well in glass terrariums or aquariums which, ideally, should be a bit longer than the snake itself and as wide as possible. Be sure to secure the tank’s screen top with cage clips, as snakes are notorious escape artists. Cypress mulch or other substrates designed for use with snakes should cover the cage bottom. A reptile-safe disinfectant should be used to swab the cage floor after the snake defecates.

Rat snakes appreciate a shelter in which to hide and a bowl large enough for soaking. The water bowl should be filled to a level such that it will not overflow when the snake enters, as damp terrarium conditions may lead to respiratory and skin infections. If space permits, a stout branch for climbing and basking should be included.

American hobbyists favor a fairly “sterile” set up for rat snakes, but in Europe they are commonly kept in large, planted exhibits. Black ratsnakes take well to these, and, while management is a bit more complicated, the range of behaviors exhibited by snakes in such settings makes the undertaking well-worthwhile. I shall write more about keeping snakes in naturalistic exhibits in a future article.

Light, Heat, Humidity, etc.
Cage temperatures should range from 75 – 82 F, with a basking spot of 88 – 90 F. This species has no need for UVB light, but full spectrum lamps emitting UVA may be of some value. The cage should be kept dry at all times (see above).

Feeding
Black ratsnakes thrive on a diet of mice and rats. They take readily to dead prey and should not be offered live rodents due to the likelihood of injury to the snake. Adults should be fed every 7-10 days.

Captive Longevity
The captive longevity record for this species is just over 34 years.

Handling
Although black ratsnakes will, like most animals, bite in self-defense, they are, as a whole, mild-tempered. Most respond well to gentle handling, but individual animals vary greatly in this regard. Never startle a snake by picking it up suddenly, and do not handle snakes after you have touched food animals. Future articles will deal with the specifics of handling in detail.

Breeding
Breeding will be covered in depth in a future article. Except for snakes originating in the southern-most portions of the range, black ratsnakes breed most reliably when subjected to a winter cooling period. This species has been bred in captivity through multiple generations.

Miscellaneous
A number of European and Asian relatives, such as the Russian ratsnake, E. schrencki, may be kept as described for the black ratsnake. Other species referred to as “ratsnakes”, such as the arboreal red-tailed ratsnake, Gonyosoma oxycephala, have slightly different husbandry requirements. Please be sure to research potential pets carefully, as trade names can be misleading.

Additional Resourceshttp://people.wcsu.edu/pinout/herpetology/eobsoleta/index.html (detailed information on natural history)