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

Southeast Asia’s bizarre tentacled snake (Erpeton tentaculatum) is a long-time favorite of mine and I’ve kept and bred a great many in zoo collections over the years.  Despite watching them intently for so long, I’ve never quite been able to figure out how they manage to so effectively catch fast-moving fishes while striking out in a direction that seems designed to insure that they miss the intended target.

A Unique Escape Strategy

Recently published (Vanderbilt University, Tennessee: June, 2009) research has provided the answer.  Many fishes, it seems, utilize an escape maneuver known as the C-Start.  Upon sensing danger, the body contorts into a “C” shape, the tail is flicked and the fish, in a millisecond, darts away.

Exploiting the Defensive Maneuver

Tentacled snakes, anchored to submerged objects by their tails and resembling water-logged roots, lie in wait for passing fishes.  The snake always holds itself in a very distinctive “J” shaped position.  As a fish approaches, the snake “feints” with its body by sending a ripple of water towards the fish.  This incites the C-Start reaction and propels the fish directly toward the snake’s jaws.

Once initiated, the C-Start maneuver cannot be altered, so the hapless fish is doomed.  The snake’s “J” position allows it to strike not at the fish but rather where the fish will be once it flees.  What’s more, the strike nearly always catches the fish in the head region, assisting the snake in swallowing its slippery prey.

Further Reading

To learn more about the natural history and captive care of tentacled snakes, please see my article The Tentacled Snake, an Unusual Pet Serpent .

Among the world’s 10,000 or so millipede species we find a number of common as well as extremely specialized creatures, many of which make interesting terrarium subjects. The commonly available giant African millipede (Achispirospreptus gigas) is, at nearly 11 inches long, a very impressive beast that may reach 10 years of age and reproduce in captivity.  A number of other species appear in the trade from time to time as well…while the largest hail from the tropics, several millipedes native to the USA, such as Narceus americanus, are also quite large, and some are brilliantly colored.

The following information applies mainly to the African giant millipede, but also holds true for many of the other large African and Southeast Asian species that enter the trade.

A Simple but Effective Feeding Technique

Judging from the questions I’ve received from millipede enthusiasts over the years, a poor diet is the main reason that these creatures sometimes fail to thrive in captivity.

One trick that I have found particularly useful is to add a handful of a reptile calcium supplement, such as Reptocal to the substrate in a millipede terrarium.  Millipedes consume a good deal of leaf litter and, in some cases, rotting wood, and will ingest calcium mixed into the litter as well.  They seem to require quite a bit of calcium, especially when molting and forming a new exoskeleton, so I powder their other food with it also.

Leaf Litter and Wood

In order to provide as much dietary variety as possible, I always keep millipedes in a substrate comprised of at least 50% leaf litter (oak, ash and other native species) and well-rotted (soft and crumbly) wood collected locally.  This is replaced periodically as the millipedes tunnel through and consume the nutrients therein.

The balance of the substrate consists of coconut husk  and top soil.  Millipedes need to burrow, especially when laying eggs and molting, so keep at least 4-6 inches of substrate available to them.  A layer of gravel at the terrarium’s bottom will assist in drainage.

Dietary Variety

As we know little about the actual nutritional needs of any millipedes, I strive to provide as much variety as possible.  This seems a useful technique, as I’ve been able to breed several tropical and native species over the years, and have kept individual millipedes for over a decade.  Please check out Part II of this article for salad recipes and other foods that have served me well over the years when keeping millipedes.

Further Reading

Please see my article Millipede Emergency for a unique twist to millipede keeping.

Since their arrival in the US in the early 1980’s, White’s treefrogs (Litoria caerulea) have become one of the most popularly kept of all frogs.  Although longevities of 25 years are known, captive breeding remains surprisingly uncommon.  The white-lipped treefrog (Litoria infrafrenata), a large, attractive relative, is also infrequently bred by hobbyists.  Considering how little we know about amphibian reproduction, and the precarious state of many species, I suggest that interested frog-keepers hone their breeding skills on the relatively robust White’s treefrog.

Distinguishing the Sexes

White’s treefrogs reach sexual maturity by age 2.  Mature males are smaller than females, have loose, slightly dark skin about their throats and, when in breeding condition, sport thickened nuptial pads (used to grasp females during amplexus) on their thumbs.  Only the males call.

The Dormancy Period

A cooling off period, preferably in late winter, is critical to breeding success. Cease feeding the frogs 7-10 days prior to the cooling period and place them into an aquarium furnished with a substrate of moist sphagnum moss and cork bark shelters.

Gradually reduce the temperature to 65 F during the night (a basement is ideal) and 68 F during the day (use a small incandescent bulb to raise the temperature) and maintain this schedule for 4 weeks.  Thereafter, hold the temperature at 65 F round-the-clock for an additional 2 weeks.  The terrarium should be kept in the dark throughout this time, and the frogs should not be fed.

Preparing the Frogs for Breeding

After the 6 week “winter”, warm the frogs to 80 F over a 2 week period, and feed them heavily for 3-4 weeks.  Novel prey animals, such as wild-caught or canned insects, should be offered at this time.

Thereafter, move the frogs into an aquarium filled with 4 inches water and provisioned with live floating plants (i.e. water hyacinth, water lettuce, pothos) and basking platforms.  Use an aquarium heater  to warm the water to 82-85F, and add a florescent bulb to encourage plant and algae growth.  I recommend the Reptisun 2.0  bulb, as its UVB output is ideal for amphibians and plants…avoid strong reptile UVB bulbs.

Using a small submersible water pump, create artificial rain by pumping water into a perforated plastic container or PVC tube placed on the terrarium’s screen cover.  Allow the “rain” to fall for 6-8 hours nightly, beginning at dusk.  This step is vital in inducing spawning, and will usually result in reproduction within a week or so.

The Eggs

If all goes well, you will one morning find yourself in possession of thousands of eggs.  It is wise to plan ahead and arrange for friends or nature centers to take some of the eggs, as crowded conditions can cause the loss of the entire clutch.  Remove the adults and install an air pump driven sponge filter that provides mild water circulation.

In contrast to what is commonly recommended for some other frogs, I suggest raising White’s treefrog tadpoles in plant and algae filled aquariums as opposed to bare, sterile containers.  I have even added green pond water to several tanks with good results.

Further Reading

You can read about White’s treefrog breeding in the wild, and hear recordings of the males’ calls, at http://magneticisland.s4space.com.au/L.caerulea.html.

Please see Parts I and II of this article for information on growing terrestrial and aquatic food plants for reptiles and amphibians.

Aquatic Invertebrates

A startling variety of aquatic invertebrates will likely establish themselves in almost any body of standing water, be it a backyard pond or a container of water on a fire escape in the heart of a busy city (the adults of most aquatic insects are winged, and quickly locate new breeding sites).  Ranging in size from tiny Daphnia to quite large dragonfly nymphs, all are fine food items for insectivorous herps, and make wonderful aquarium subjects as well.

You can also use an outdoor pond to breed snails, guppies, crayfish and other useful food animals.

Terrestrial Invertebrates

Your reptile garden will, in addition, attract numerous terrestrial insects.  All are interesting to observe and many can be collected to feed to your collection (a Bug Napper Insect Trap situated near a garden will provide a great nightly haul).

Flowering gardens are also important as feeding sites for pollinating insects, many of which are in serious decline.  Over 80% of the world’s plants and 90% of US food crops rely upon insect pollinators.

A Bonus…Observing Garden Visitors

You are sure to come across some interesting finds, as invertebrate diversity, even in temperate areas, is astounding.

An acre of Pennsylvania soil, for example, can host 425 million individual invertebrates (including 2 million tasty earthworms!) and New York State is home to 4,125 species of beetles.  Over 11,000 different types of moths may be found in the USA, and new species are constantly being uncovered in the most unlikely of places…be sure to check those captured in your Bug Napper carefully before popping them into a terrarium!

Further Reading

The leaf fall that gathers below your plants and trees will quickly become populated by an unbelievable assortment of millipedes, springtails, sow bugs, beetles and other creatures.  Many of these, especially the smaller invertebrates, are vital foods for tiny poison frogs and other small herps.  For information on collecting and using this free food source, please see my article on Leaf Litter Invertebrates.

Image referenced from Wikipedia and originally posted by Alvesgaspar

Please see Part I of this article for general information on some of earth’s most toxic amphibians (if not creatures in general) and for additional newt-keeping observations.

Tiny Newt vs. Giant Toad

The familiar red-spotted or Eastern newt (Notopthalmus viridescens) is at its most toxic in the immature eft (land) stage, but the aquatic adults are none-the-less well protected.

Decades ago, the mascot of an animal importer for whom I worked was a huge marine toad (Bufo marinus).  In those days, animals imported from then French Guyana were particularly massive, and this friendly, 4 pound+ specimen was no exception.  Imported animals which did not thrive following their long journey to the USA, ranging from giant Vietnamese centipedes to small rats and finches, all went to filling this amphibian behemoth’s huge appetite.

As a naïve 13 year old animal caretaker, I once tossed a nearly dead, 3-inch- long Eastern newt to the toad.  The newt was swallowed immediately and, right before my eyes, the toad flipped over…dead (along with my budding career!).  Years later, a co-worker reported a similar incident involving a Western painted turtle (Chrysemys picta bellii).

Interesting Means of Toxin Introduction

Several salamanders have quite unique ways of distributing their protective secretions – fire salamanders (Salamandra salamandra), for example, can squirt theirs for some distance.  Perhaps strangest of all, the Spanish ribbed newt (Pleurodeles waltl) actually drives toxin-tipped ribs through the skin of its back when confronted by a predator!

Cautions regarding Pet Newts and Salamanders

Highly toxic newts and salamanders, including all mentioned in this article, are widely available in the pet trade.  Many make interesting and long-lived pets.  However, please treat all newts and salamanders with caution…always wash well after handling them (most need not be handled, and none appreciate it) and, of course, do not trust them around children, mentally challenged persons, or pets.

Further Reading

Please check out my book Newts and Salamanders  for more information on the natural history and captive care of red-spotted newt, ribbed newts, fire salamanders and their relatives.

Image referenced from Wikipedia and originally posted by Peter Galaxy.