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

Click: Emperor Scorpion, Pandinus imperator, Care – Part 1, to read the first part of this article.

Heat, Humidity and Light

Temperature should be maintained at 78-86 F, and humidity at 70-85%.  Do not cover the terrarium’s top with plastic in order to increase humidity, as air circulation is desirable.  Rather, use a moisture-retaining substrate (please see above) and spray frequently with de-chlorinated water (the substrate should be slightly moist to the touch).

In order not to disturb your scorpions at night, heat should be provided by an incandescent “nocturnal” bulb; this will also allow you to observe your pets when they are most active.  A ceramic heater may also be used.

Due to peculiarities in molecular structure of the exoskeleton, scorpions fluoresce under UVB light.  Despite having discovered this in the 1940’s, scientists cannot as yet determine why such a facility should exist. The fluorescent sheen they exhibit is quite unearthly…a UVB-lit scorpion exhibit that I maintained at the Bronx Zoo has long been a favorite of visitors.  Try lighting your scorpions with a UVB bulb at night…and while you’re at it, please see if you can find out what is going on with their fluorescence!

Feeding

Scorpions should be offered a wide range of soft-bodied invertebrates, including crickets, roaches, waxworms, silkworms and butterworms; some individuals will accept earthworms as well.  Do not rely on crickets as a dietary mainstay; rather, provide as much variety as possible.  In the warmer months, I feed mine mainly on wild caught moths, earwigs, caterpillars, katydids, crickets and soft-bodied beetles (Zoo Med’s Bug Napper is an excellent insect trap).

Emperor scorpions take readily to tong feeding , and should be provided with canned grasshoppers and silkworms as a means of increasing dietary variety.  We know nothing of their vitamin/mineral needs…I powder my scorpions’ food once weekly with a reptile dietary supplement  as “insurance”.

Emperor scorpions may on occasion take small frogs, lizards and even nestling rodents in the wild.  This is almost certainly a rare event…vertebrate food is not required in captivity.

Water should be provided in a shallow, easily-exited water bowl.

Social Grouping/Compatible Species

Emperor scorpions present the opportunity for fascinating studies in the evolution of social behavior.  Despite being as close to “living dinosaurs” as we are likely to see, these ancient animals exhibit complex social behaviors.  In the wild, they often live in discreet groups that occupy a single, extensive system of burrows.  We know little about the functioning of these groups.  The young of emperor and other highly social scorpions remain dependent upon their mothers for longer than do other species, but other than that, specific details are lacking.

As emperor scorpions readily exhibit natural behaviors when properly housed in captivity, the research potential for interested hobbyists is enormous.  I urge you to seriously consider working with this fascinating creature.

Captive groups almost always co-exist peaceably, provided they are given ample space and hiding/burrowing areas.  Females that breed in group situations require special attention…I’ll address this in an article on reproduction shortly.  Emperor scorpions will attack and/or consume other types of scorpions.

Further information and references to papers on emperor scorpions is posted at

http://www.ub.ntnu.no/scorpion-files/p_imperator.php

One of the world’s largest scorpions, the emperor is also the most widely kept, and captive born specimens are readily available.  Other than females with young on their back, emperor scorpions are rather mild-mannered.  The sting may be painful, but is not considered dangerous to healthy adults.

Physical Description

Females may reach 7 inches in length and, when gravid, exceed 50 grams in weight (by way of comparison, the average house mouse weighs 20 grams); males are slightly smaller.  Both sexes are jet black in color.

Range and Habitat

Emperor scorpions thrive in areas of high humidity, and are generally associated with rainforests.  There are some reports of populations living in wet savannas and human-influenced habitats as well.  They are native to northwest and north-central Africa, with their range extending from Mauritania south and east to Zaire.

Status in the Wild

Wild populations have been little-studied, but concern over huge exports in the early 1990’s led to the listing of this species on CITES II.  Those in the US trade are largely captive bred, although animals “ranched” in Togo and Benin are sometimes imported.  The closely related P. dictator and P. gambiensis, uncommon in the pet trade, are also listed on CITES II.

CAPTIVE HUSBANDRY

The Enclosure

Provide your scorpions with as much space as possible.  A pair can be kept in a 10 gallon aquarium, but larger is always better; a 20 gallon can support 4-6 animals.  The screen cover should be secured with cage clamps.

Physical Environment – Habitat Type and Terrarium Decorations

Emperor scorpions inhabit extensive burrow systems in the wild, and should be given the opportunity to burrow in captivity.  Under such conditions, they will exhibit a wide range of interesting behaviors – far more so than if kept in a simple terrarium.  When able to construct secure burrows, captive scorpions become quite confident and therefore more likely to show themselves.

Emperors also take readily to artificial caves  and hideouts excavated below driftwood and other structures.  I once created a very interesting exhibit by partially burying a number of artificial caves at different levels within the substrate of a 55 gallon aquarium.  The resident colony of emperor scorpions dug pathways between the various cave entrances and established a complicated maze of “avenues” – more reminiscent of rodent runways than anything one might associate with an invertebrate.  I highly recommend this type of set up for your scorpions.

Substrate

Excavator Clay Burrowing Substrate  is specifically designed for fossorial animals and is a great choice for burrowing scorpions.   A few handfuls of Jungle Earth Reptile Bedding  should be mixed in to help retain moisture.

Click: Emperor Scorpion, Pandinus imperator, Care – Part 2, to read the second part of this article.

Writing in the current issue of the journal Animal Behavior, researchers from the University of Grenada report that female Mexican lance-headed rattlesnakes frequently consume infertile eggs and non-living young after giving birth.  This is said to be the first documented case of cannibalism among rattlesnakes (please see below for my observations, however).  Interestingly, with a sole exception, the females did not consume young that were born alive, even though these remain inactive for several hours after birth, and appear (to us, at least!) to be dead.

Rattlesnakes bear live young, and females use up a great deal of energy and body mass during gestation (they do not feed while gravid).  It is theorized that consuming those young which are dead upon birth helps them to recover their strength.

Rattlesnake Cannibalism in another Species

While working with the comprehensive rattlesnake collection at NYC’s Staten Island Zoo, I had the opportunity to participate in breeding efforts for a number of species.  Most births occurred at night and were not filmed, so I cannot say if females of other species ever consumed non-living young.  However, newly born Neo-tropical rattlesnakes (Crotalus durissus) did consume litter-mates on two occasions.

Hog Fat and other Unusual Snake Foods

Contrary to popular belief, many snakes consume non-living prey (i.e. carrion) in the wild.  The most unusual incident I recall was a note published in the journal Herpetologica…a water moccasin (Agkistrodon piscivorous) was observed stripping fat from a road-killed feral hog!

Of the snakes I have worked with in the field and captivity, moccasins, indigo snakes, black racers and anacondas stand out as taking the widest variety of prey species, and each engages in cannibalism.  One particularly large moccasin I cared for consumed a northern water snake that shared its exhibit (not my idea – I had moved on by then!!).  I’m sure the same occurs in the wild, in areas where moccasins and various water snakes co-exist.

A Collection for Rattlesnake Aficionados

I had the wonderful opportunity of participating in the renovation of the Staten Island Zoo’s reptile house, former stomping ground of legendary snakeman Carl Kauffeld (known to all snake keepers as the author of Snakes, the Keeper and the Kept and Snakes and Snake Hunting).

As in former times, the zoo now boasts an impressive rattlesnake collection…please visit if you have the opportunity.  Pictured here are a few exhibits that I set up for the opening – Neo-tropical rattlesnakes, banded rock rattlesnakes and desert Massasaugas.

Further Reading

Lance-headed rattlesnake photos and natural history information are posted at:

http://www.ratelslangen.nl/gallery/Crotalus_polystictus_Mexican_lance-headed/

Breeding Leopard Geckos (Eublepharis macularius) at Home: Determining the Sex of Your Pets

The ever popular leopard gecko is a good choice as an introduction to the breeding of lizards in captivity. Success, while not assured, is common…yet, these little fellows are so captivating that even zoos and well-experienced breeders continue to work with them.

Spring’s Effect
Leopard geckos are often brought into breeding readiness by the slight changes in temperature and day length that are evident even indoors. With the imminent arrival of spring (writing from southern NY I am happy to report hearing a song sparrow singing for the first time today!), I thought it a good time to discuss how female from male leopard geckos differ in appearance.

The Pores
Take a look at your pet’s vent, which is an opening, used for copulation and defecation, at the base of the lizard’s tail. Directly above the vent, between the rear legs, you will see a series of “V” shaped little bumps, which are known as pre-anal pores. These are large and readily visible in males and tiny and less-evident in females. The pores produce waxy secretions that are used by males to mark territories and, possibly, to attract females.

Hemipenes
Between the vent and the base of the tail, mature male geckos exhibit a pair of bulges. These bulges conceal the hemipenes, which are used during copulation to achieve internal fertilization. Male lizards and snakes have 2 hemipenes, and can use either, but only one at a time, when mating.

Practice!
You may need to look at a number of geckos, or reliable photographs, before being able to reliably distinguish males from females…but once you get the right “search image” the process becomes quite easy. Please remember that only mature animals – males of age 1 year or more, females generally of age 18 months or so – will exhibit noticeable sexual dimorphism (differences in appearance).

Further Reading
Please check out the book I’ve written on leopard gecko care and natural history at http://www.thatpetplace.com/pet/prod/240453/product.web.

See Feeding Pet African Bullfrogs Pyxicephalus adspersus – Part 1 for the first part of this article.

How does one satisfy a 9 pound amphibian!?

Wild-Caught Insects
Native invertebrates, collected from pesticide-free areas, should be offered whenever possible. In my work with frogs of all types, I’ve found very little that approaches the beneficial effects of a varied diet. Zoo Med’s Bug Napper is an excellent insect trap.

Sweeping a net through tall grass and searching around outdoor lights will also yield a number of useful species. Avoid using spiders, stinging and brightly-colored insects and fireflies, and do not collect during times when your collecting site is being sprayed with insecticides as part of mosquito control programs.

African bullfrogs under my care have enthusiastically accepted (“enthusiastically” goes without saying where these stout fellows are concerned!) cicadas, katydids, grasshoppers, beetles and their grubs, moths, tree crickets, hover flies, caterpillars, and most everything else I could come up with. I rely heavily upon wild-caught invertebrates throughout the spring, summer and early fall, but even a few beetles plucked from a screen door every night or so will go a long way in keeping your pet in the peak of health.

The Importance of Canned Insects
African bullfrogs can be easily trained to accept non-living food items from a plastic feeding tongs (well, to be honest, no actual “training” is involved…they generally just swallow whatever moves within range!). They have a very vigorous feeding response, and hit food quite hard. Accordingly, I avoid using metal feeding implements, as the risk of a mouth injury is fairly high.

This frog’s willingness to tong-feed is quite fortunate, because it enables us to use canned insects as a source of important dietary variety. The canned grasshoppers are quite large, and are suitable even for adult African bullfrogs. Large canned grasshoppers, silkworms and other insects can be broken into smaller pieces for juvenile frogs.

Meal Frequency and Nutritional Supplements
Juvenile frogs can be fed 3-4 times weekly, while adults do fine with a meal each 4-7 days (fast them for 10 days or so after a “heavy” meal of large shiners or pink mice). Smaller, more frequent meals can also be offered…I personally find this preferable, but it is not as critical for with this species as it seems to be for certain others.

The food of juveniles should be powdered with Reptocal at every other feeding, that of adults once weekly. During periods when you are unable to offer a varied diet, alternate Reptocal with Reptivite.

The African bullfrog pictured here may be seen in the wonderful amphibian exhibit area at Norwalk Connecticut’s Maritime Aquarium. I was involved in the project’s development as a consultant, and am pleased to say that the staff has done an excellent job of keeping and breeding a wide variety of amphibians in beautiful, naturalistic exhibits. The accompanying photographs show some of the aquarium’s other residents – albino American bullfrogs with pumpkinseed sunfishes, poison frogs and tiger salamanders. Also exhibited are barking treefrogs, Surinam toads, bronze frogs, mudpuppies, fire salamanders, red-eyed treefrogs and many other toads, salamanders and frogs from both the USA and abroad – please visit if you have the opportunity.

Further Reading
For a startling account of African bullfrog predation upon red spitting cobras and of the amazing degree of parental care these frogs provide to their tadpoles, please see my articles “An Appetite for Cobras” and “The African Bullfrog (South African Burrowing Frog, Giant Bullfrog), Pyxicephalus adspersus: The World’s Heaviest Frog is also a Devoted Parent”.

African bullfrogs seem to give rise to all sorts of interesting stories.