Reptiles and Amphibians in Outdoor Pens or Ponds: Preparing for Winter

Backyard pond

Uploaded to Wikipedia Commons by Nowis

I’ve always enjoyed keeping my herp pets, and those I’ve cared for in zoos, in outdoor ponds and exhibits. I see a wider variety of behaviors and have better breeding results, and the access to natural sunlight and wild insects is very beneficial for the animals. The arrival of winter, however, ends the fun and brings special challenges. Today I’ll cover indoor and outdoor hibernation of terrestrial and aquatic turtles and frogs, and review what to do if you wish to keep your pets active year-round.


General Considerations

Hibernation is risky under the best of circumstances. Each spring, I see evidence of winter die-offs among free-living reptiles and amphibians. The safest option for most pet owners is to keep your animals active and feeding throughout the winter.


Reptiles and amphibians native to temperate climates may not reproduce unless subjected to period of dormancy. However, in many cases a short, cool resting period will suffice – true “winter” in not needed.   Details vary widely as to species, so please post below for further information.


Green frogs in amplexus

Uploaded to Wikipedia Commons by Greenfrogmaster

It has been theorized that hibernation enhances the long-term health of those species that do so in the wild, but there seems to be nothing of substance published to this effect. During my long career in zoos, I’ve kept hundreds of temperate zone species active and breeding year-round for many years. In my personal collection, a number of North American natives, including 30-45 year-old-turtles and salamanders aged 20-35 years, have never experienced dormancy.


Animals subjected to hibernation must be healthy, well-hydrated, and possessed of ample fat reserves; a vet exam in early autumn is recommended.


Depending upon the species and the size of the individual, pre-hibernation preparation should include a fast of 1-4 weeks in duration (please post below for further information).


Eastern Box Turtle

Uploaded to Wikipedia Commons by Stephen Friedt

Outdoor Hibernation

Box Turtles and Toads

I’ve had good results by allowing Eastern Box Turtles and American Toads to dig down into the soil and leaf litter within their pens. However, the ground must be loosened in the fall, and I always add a 6-12 inch layer of fallen leaves to the surface. Note: although many people keep American Wood Turtles in largely-terrestrial pens, they spend the winter at the bottom of streams, not on land.


The pen should be exposed to rainfall year-round, as terrestrial turtles and toads require somewhat moist hibernation sites. Drainage must be provided…I’ve only left animals outdoors in bottomless pens, so that water does not pool.


Eastern Painted Turtle

Uploaded to Wikipedia Commons by Greg Schechter

Aquatic Turtles and Frogs

Red-Eared Sliders, Painted Turtles, Green Frogs, American Bullfrogs and similar species usually overwinter underwater, beneath mud and leaf litter. Unless you are well-experienced or have expert guidance, I would not recommend trying to keep these creatures outdoors for the winter.


Dormant turtles absorb oxygen via the cloaca, while amphibians utilize diffusion through the skin. Your pond water’s oxygen level is, therefore, critical, but we have little information on any species’ exact requirements. Water depth is also a concern.


Aerators and surface heaters designed for use with koi and goldfish can be employed if you wish to keep your aquatic pets outdoors. You can read more about general winter pond preparations on ThatFishBlog…please see the links below.


I have had success in overwintering some aquatic species outdoors (i.e. Sliders, Snappers, Musk, Mud, Spotted and Painted Turtles, Green and Bullfrogs, Northern Watersnakes) but my best results were in large outdoor zoo exhibits rather than backyard ponds.


In both my pens and natural situations, I was several times surprised to find American Bullfrogs and Green Frogs hibernating on land – they missed the “go to the pond memo”, I guess!


Indoor Hibernation

Indoor hibernation is a bit less risky in some ways, as you can monitor the animals closely and avoid the extreme conditions that occur outdoors. However, it is still not advisable for pet-keepers lacking considerable experience.


American Box Turtles can be over-wintered in moist sphagnum moss at 38-42 F. A refrigerator designated for this purpose is ideal, but attics, garages and similar areas can be used if temperatures are appropriate. American Toads and their relatives can be maintained in the same manner, but they usually remain active and feeding down to 55 F or so, and so are easier to “keep awake”.


Keeping your pets in an unheated or extra-cool room of the house is not satisfactory. At temperatures too low for normal activity, yet above those needed for dormancy (i.e. 50-65 F for many temperate zone species), food reserves are used and the immune system fails to protect from respiratory and other infections.

While aquatic turtles and frogs have been successfully over-wintered in aerated water at 40 F, I would not advise taking the risk.


Avoiding Hibernation

Spotted, Wood, Box and Painted Turtles, and others with similar life histories, may be kept active at their normal temperatures year-round. I tend to maintain them at the lower end of their normal active range, but provide a warmer basking site. If the animals are in good health, a dip to 60 F at night will do no harm (different species vary in this regard – please post below for specific information).


Gray Treefrogs in amplexus

Uploaded to Wikipedia Commons by Fredlyfish4

Temperate zone frogs and toads, including Fire-bellied Toads, American Bullfrogs, Gray Treefrogs and Leopard Frogs remain active and feeding at normal to low (i.e. 55 F) room temperatures. The change from summer highs seems to do them good, and in some cases (i.e. Fire-bellied Toads), may also stimulate breeding behavior.



Russian and Greek Tortoises, along with several other species, experience cool to cold winters in some portions of their natural ranges. However, it is difficult to successfully induce dormancy among captives, either in the home or outdoors. Please post below if you wish to attempt this, and I’ll send along specific information.


Internal Controls on Behavior

Circadian rhythms, which might be likened to “internal clocks”, govern behavior to varying degrees. For example, Indian Gharials under my care for 14 years refused food in tune with the cool season in their native range, despite being kept at optimal temperatures (they lost virtually no weight during the 3 month period, however).


Among pets, wild-caught individuals of certain species may refuse food and become less active even when kept warm during the winter. In some cases, captive-born youngsters of the same animals will feed normally all winter long. Captive born individuals of other species may enter semi-dormancy despite being many generations removed from the wild. For species with large ranges, the origin of the parent stock may be important. I’ve had experience with this scenario in a number of reptiles and amphibians, and am very interested in learning more…please post your observations and questions below.


Hi, my name is Frank Indiviglio. I’m a herpetologist, zoologist, and book author, recently retired from a career spent at several zoos, aquariums, and museums, including over 20 years with the Bronx Zoo.


Please check out my posts on Twitter and Facebook.   Each day, I highlight breaking research, conservation news and interesting stories concerning just about every type of animal imaginable. I look forward to hearing about your interests and experiences as well, and will use them in articles when possible.


Please also post your questions and comments below…I’ll be sure to respond quickly. Thanks, until next time, Frank.


Further Reading

 Preparing Your Pond for Winter

Bullfrogs in Backyard Ponds

Red-eared Sliders in Backyard Ponds

Exciting New Exotic Animal Displays in our Reptile Room

In the Reptile Room section of our Lancaster, Pennsylvania retail store, our expert staff is always creating new and exciting displays.  These amazing displays rarely get the exposure they deserve – so we wanted to take a moment and highlight their extraordinary work on That Reptile Blog. Check them out below or stop by our store and see for yourself!



Mantella Tank

This display features the unique Mantella frog (Mantella ebenaui) in a 40 gallon Marineland Perfecto aquarium.  The brown variety of this rare frog is native to Madagascar.  The landscape includes river rock gravel, topped with several live plants, including creeping fig, liverwort and begonia.  The staff has also included a mini water reservoir with several small goldfish.



What makes this set up special, is that the tank is fully sustaining ecosystem that requires no filtration and little maintenance.  The system relies on the live plants and gold fish to digest nutrients created by the breakdown of uneaten food and waste.  The only maintenance required is feeding the Mantella and trimming back plants as needed.  This set up is maintained by several members of our staff, including Josh Mangan.




 IMG_0876Volcano Tank

This awesome “active” volcano was handcrafted by our Reptile Room associate Jesse Taylor.  The inventive design includes a Zoo Med Repti-Fogger surrounded by natural Eco Earth bedding.  The fogger releases a steamy mist that creates the appearance of volcanic activity.  Housed in an 18 in. x 18 in. x 24 in. Exo Terra Glass Terrarium, the ecosystem also includes an Eco Earth and live seasonal moss base, as it is prepared to hold African Reed Frogs.



IMG_0952Customized Blue Gliding Frog Terrarium

Created by Reptile Room supervisor Ryan Chillas, this great set up features two Vietnamese Blue Gliding Frogs.  To best replicate the natural environment of the frogs, Chillas created a detailed, natural set up that includes a water reservoir and waterfall.  He added a river rock base and several live plants, including creeping fig, liverwort and a peace lily.

To create the waterfall, Chillas borrowed some non-toxic expanding foam sealant from our pond section.  He used it to fashion a back wall that holds an Aquatop fountain pump.  The pump draws water from the bottom reservoir and moves it to the top of the foam wall.  Chillas also added petrified wood and rocks throughout the foam wall.  Adding live plants, it creates the perfect climbing environment that the arboreal Blue Gliding Frogs would find in their natural habitat.


If you’d like to check out these great displays, stop by our Reptile Room in our Lancaster, Pennsylvania store. In addition to these animals, we also have a large variety of lizards, tortoises and spiders to pique your curiosity.  You can check with Josh, Jesse or Ryan in person or speak with any of the members of our helpful expert staff.  We are always ready, willing and able to answer any questions you might have!





My Experiences with Snake Necked Turtles in Zoos and at Home

Giant Snake Necked Turtle

Uploaded to Wikipedia Commons by Sam Fraser-Smith

Among the Snake Necked Turtles of the family Chelidae we find some of the world’s most unique and effective reptilian predators. I’ve had the good fortune of knowing many, including a few that were newly-described; all have been fascinating to keep. From the massive Giant Snake Neck (Chelodina expansa), which snatches fish with blinding speed, to the bizarre Mata Mata (Chelus fimbriatus), which sucks them down like a vacuum cleaner, all have their surprises and secrets. While many are suited only for experienced keepers with room to spare, others are quite hardy and suitable for most serious turtle enthusiasts.



The world’s 56 Snake Necked Turtles are classified in the family Chelidae. Their trademark necks, which are snake-like in both length and striking speed, render the family unique among all the world’s turtles.



Snake Necked Turtles range from 6 to over 20 inches in length. Those with the most impressively-long necks are found in the genus Chelodina. Most of those native to Australia, New Guinea and Indonesia are strong swimmers with streamlined carapaces and fully-webbed feet. Others, such as the New Guinea Snapping Turtle (Elseya novaeguineae) have shorter (but still long!) necks and somewhat domed shells. All withdraw the neck into the shell on a sideways angle rather than straight back, as is typical for “regular” turtles.


The South American members of the family vary greatly in appearance, and do not have the outlandishly-long necks typical of their Australasian cousins. One of these, the Mata Mata (Chelus fimbriatus), is perhaps the world’s most unusual turtle. The broad flattened head of this aquatic creature, adorned with skin tubercles and flaps, and bearing a long, pointed snout, does not appear to belong to a turtle…or to any animal for that matter!

Neck withdrawn (New Guinea Snapping Turtle)The skin flaps may attract fish, which are sucked into the huge mouth when the throat distends, creating a vacuum-like action. Those I’ve kept (please see photo) have also accepted tadpoles, shrimp and other aquatic invertebrates. Ranging from Venezuela and Surinam to Columbia, eastern Peru and northern Brazil, this black water river denizen commands high prices in the pet trade, and is best reserved for well-experienced keepers.



Snake Necked Turtles are found in Australia, New Guinea, Indonesia and South America. With the exception of the equally-unusual Fly River Turtle, they are the only freshwater turtles native to Australia and New Guinea.



Most Australasian species spend the majority of their lives in water, emerging only to bask or deposit eggs. South American representatives vary in their habits – the Mata Mata Turtle is completely aquatic but others, such as the Twist Necked Turtle (Platemys platycephala), spend some time on land.


Depending upon the species, fast-moving rivers, swamps, lakes, flooded grasslands, tidal streams and other aquatic habitats are occupied.


Twist necked Turtle

Uploaded to Wikipedia Commons by

Care and Feeding

Snake Necked Turtles are highly carnivorous, although some add fallen fruit and aquatic plants to the diet. Those with very elongated necks, such as the Giant Snake Necked Turtle (Chelodina expansa), strike at swimming fish with lightning speed, and rarely miss. In my experience, only the Common Snapping Turtle and some of the Softshells (most notably the huge Narrow-Headed Softshell, Chitra indica), can equal their amazing striking speed; none snare fish so efficiently.


Fish are favored by most, but tadpoles, crayfish, snails, carrion, worms, and insects are also taken; larger species occasionally add small lizards, frogs, snakes, and mammals to the diet.


Pet Snake Necks fare best on a diet comprised largely of whole organisms such as earthworms, occasional pre-killed pink mice, crayfish and fresh water minnows and shiners. A steady diet of goldfish has been linked to several health concerns among Mata Mata Turtles, so in zoos we avoid or strictly limit their use in general.   Super mealworms, roaches, crickets and other insects can be used to vary the diet. Many refuse dry turtle foods, at least initially, but the products sold by Zoo Med and other well-respected companies are worth experimentation.


The calcium requirements of all species are likely quite high, with whole freshwater fishes being the most important source of this mineral. Some have done well without UVB exposure, but most successful private and professional keepers provide access to a UVB bulb.


All Australasian and most South American species are sizable, active turtles that require spacious aquariums equipped with sturdy basking sites, heaters and powerful filtration. While a 55 gallon aquarium might suit the smallest Snake Necks, larger species need tanks of several hundred gallon capacity, or commercial turtle tubs and ponds.

Temperatures should range from 72-80 F, with a basking site of 85-95 F, but the requirements of each species vary somewhat. Please post below for detailed information on the individual turtles in which you are interested.

Hi, my name is Frank Indiviglio. I’m a herpetologist, zoologist, and book author, recently retired from a career spent at several zoos, aquariums, and museums, including over 20 years with the Bronx Zoo.

Please check out my posts on Twitter and Facebook.   Each day, I highlight breaking research, conservation news and interesting stories concerning just about every type of animal imaginable. I look forward to hearing about your interests and experiences as well, and will use them in articles when possible.


Please also post your questions and comments below…I’ll be sure to respond quickly. Thanks, until next time, Frank.


Further Reading

Reptile Aquariums and the Nitrogen Cycle

Nest Sites for Captive Turtles

Endangered Species Notes: Missing Frogs Found, Others Feared Extinct

Indian Dancing Frog

Uploaded to Wikipedia Commons by SathyabhamaDasBiju

In 2010, 33 teams of researchers set out across 21 countries to search for the hundreds of amphibian species that may have been driven to extinction in recent years. A “100 Most Wanted” and a “10 Ten” list was compiled, and the public’s help was sought. Now, 4 years later, we have both discouraging and promising news, with some lost species “resurrected”, several new ones described, and no sign at all of many.


I’ve written about the global amphibian decline, spurred by an emerging disease (Chytrid fungus outbreak), habitat loss, and other factors, in several articles (please see Further Reading, below). The current search for survivors is also covered in the recently-published book In Search of Lost Frogs. Today I’d like to summarize recent reports from the field. Most of the good and bad news centers on frogs…the status of many salamanders, which are less well-studied and harder to find, remains unknown.


Painted Hula Frog

Uploaded to Wikipedia Commons by Mickey Samuni-Blank

Down But Not Out

To start off on a positive note, I was happy to learn that 6 frog species that had not been seen in over 20 years were found in a single week of searching on Haiti! Hopefully, surveys of other habitats that have been studied in recent years will turn out as well.


Several species on the “Most Wanted List”, all feared extinct, have also been found. Included among these are:


Ecuador’s Rio Pescado Stubfoot Toad, formerly known only from drawings.

The Borneo Rainbow Toad, which had not been seen in 87 years.

Israel’s Hula Painted Frog, which was pushed to near-extinction by marsh drainage and introduced fish.

Newly-Discovered Species

Happily, a number of species new to science turned up during the worldwide search, and in conjunction with related efforts. While many are tiny and are noted only by frog enthusiasts, several have, for various reasons, also aroused some public interest:

Named due to its (perceived!) resemblance to a character on The Simpsons TV show, the Monty Burns Toad had been hidden away in Columbia. Another surprise, a neon-orange Dart Poison Frog found in Panama, measures only 12.7 mm in length – the smallest among a huge array of tiny relatives.

Display of male Dancing Frog

Uploaded to Wikipedia Commons by SathyabhamaDasBiju

My favorites are the 14 species of Dancing Frogs recently found in India’s forests. Because they live near rushing streams that would drown out mating calls, the tiny males have evolved an alternative way of attracting mates. True to their name, they whip their rear legs about in a variety of “dance-like” moves (please see photo).


Still Missing

Unfortunately, many species remain undetected. Some, such as the Mesopotamic Beaked Toad, have not been found despite extensive surveys. Others that are hopefully skilled at avoiding herpetologists rather than gone forever include:



Uploaded to Wikipedia Commons by Arne Hodalič

Fantastically colored in greenish-yellow and jet black, the bromeliad-dwelling Jackson’s Climbing Salamander has not been observed in its native Guatemala since 1975.


Turkestanian Salamander: Known only from two specimens collected in Kyrgyzstan, Uzbekistan or Tajikistan, this salamander has not been seen since its discovery in 1909.


Golden Toad: This brilliantly colored Costa Rican native, despite inhabiting isolated, pristine cloud forests, has been missing since 1989.


Hi, my name is Frank Indiviglio. I’m a herpetologist, zoologist, and book author, recently retired from a career spent at several zoos, aquariums, and museums, including over 20 years with the Bronx Zoo.

Please check out my posts on Twitter and Facebook.   Each day, I highlight breaking research, conservation news and interesting stories concerning just about every type of animal imaginable. I look forward to hearing about your interests and experiences as well, and will use them in articles when possible.


Please also post your questions and comments below…I’ll be sure to respond quickly. Thanks, until next time, Frank.


Further Reading

Public Help Needed in Amphibian Search

Rare but Unprotected US Amphibians

US Reptiles and Amphibians Need Hobbyist’s Help

Rainbow Snake Care: Keeping a Colorful but Difficult Aquatic Snake

Rainbow Snake

Uploaded to Wikipedia Commons by Alan Garrett

Once seen, the beautiful and aptly named Rainbow Snake (Farancia erytrogramma erytrogramma) is not easily forgotten. Yet it remains relatively unknown in the pet trade, principally because of its odd dietary requirements. However, some enterprising snake enthusiasts have found ways to surmount these difficulties, and there have even been a few breeding successes. In my opinion, these unique US natives deserve much more attention, and have great potential as fascinating additions to the collections of experienced snake keepers.



Rainbow Snakes average 3 to 4 feet in length, with a record of 5 feet, 6 inches. Even after a lifetime of snake-keeping, the first I saw stopped me in my tracks. Vivid red and yellow stripes line the blue-black body, while the underside is orange to red in color.   Smooth, glossy scales add to the brilliance of these colors. The tail’s terminal scale is hard and somewhat sharp, leading some to mistakenly believe that the Rainbow Snake can “sting” its enemies.


Mud Snake

Uploaded to Wikipedia Commons by John Sullivan

Its closest relative appears to be the Mud Snake, F. abacura (please see photo). Similar in appearance and habits, the Mud Snake is also largely ignored by hobbyists and zoos.



Known in some locales as the Eel Moccasin, the Rainbow Snake may be found from southern Maryland to eastern Louisiana and central Florida.


A subspecies, the Seminole or South Florida Rainbow Snake (Farancia e. seminola), is limited in range to Lake Okeechobee in Florida. It is known from only 3 specimens, and has not been seen since 1952. Some fear that the Seminole Rainbow Snake is extinct, but I hold out hope that its secretive habits (and lack of interest!) are responsible for the lack of recent sightings.


Rainbow Snake habitat

Uploaded to Wikipedia Commons by Kej605


These largely-aquatic snakes favor cypress swamps, marshes, oxbow lakes and other sluggish bodies of water, but sometimes forage in nearby fields. Much of its time is spent among floating vegetation or, when on land, within shallow burrows.



An average-sized adult Rainbow Snake can be kept in a 55 – 75 gallon aquarium. They are not comfortable unless able to burrow, so cypress mulch, eucalyptus bark and similar materials should be used as substrates. Despite their aquatic tendencies, Rainbow Snakes may develop fungal skin disorders if unable to dry off; we see this in North America’s watersnakes (Nerodia spp.) as well. The substrate may be kept slightly moist, but dry surfaces (i.e. bark slabs) must be available.


A large water bowl, filled to a point where it will not overflow when the snake enters, will suit their needs. If the snake seems ill-at-ease, floating plastic plants should be placed in the water so that it can shelter below.

An ambient temperature of 75-80 F and a basking temperature of 85-88 F should be established.



Wild Rainbow Snakes seem to feed almost exclusively upon American Eels.   Other fishes, and aquatic salamanders such as amphiumas and sirens, may also be taken (as is the case for the related Mud Snake), but field research is lacking.


Most adult captives refuse all food except American eels. However, scenting minnows, shiners and other fishes with eels has resulted in acceptance. Another option is to search for small eels at bait stores; adult eels can be purchased at food markets and frozen until needed for scenting or use as a meal.


Young American Eels

Uploaded to Wikipedia Commons by Uwe Kils

Young Rainbow Snakes are easier to please than adults, and generally accept minnows, shiners, and a variety of other small freshwater fishes. Tadpoles are said to be the preferred food of smaller individuals in the wild; frogs and salamanders are also consumed.


General Care

In common with other fish-eaters, Rainbow Snakes produce copious, watery waste products and require more upkeep than similarly-sized rodent-eating snakes. As nearly all individuals encountered in the trade are wild-caught, new arrivals should be seen by a veterinarian.



Captive breeding is rare, although this seems due more to a lack of interest than any inherent difficulties. A slight drop in temperature (68 F by night, 72-80 F by day) may stimulate breeding. Pairs must be monitored carefully, as biting may occur during courtship.


Rainbow Snakes produce unusually large clutches, which range in size from 20 to over 50 eggs. As the eggs are deposited below cover or within shallow burrows, a large nesting box should be provided to gravid females. Hatchlings measure 8 ½ – 11 inches in length.



Rainbow Snakes are rather inoffensive, although like all snakes they may bite and should be handled with care. Their first line of defense is usually to thrash about while pressing the hard, terminal scale of the tail against one’s flesh. This can do no harm, but folks who are unprepared may drop the snake in response. This defense mechanism has resulted in their being dubbed “stinging snakes” in some regions.

Hi, my name is Frank Indiviglio. I’m a herpetologist, zoologist, and book author, recently retired from a career spent at several zoos, aquariums, and museums, including over 20 years with the Bronx Zoo.

Please check out my posts on Twitter and Facebook.   Each day, I highlight breaking research, conservation news and interesting stories concerning just about every type of animal imaginable. I look forward to hearing about your interests and experiences as well, and will use them in articles when possible.


Please also post your questions and comments below…I’ll be sure to respond quickly. Thanks, until next time, Frank.


Further Reading


Watersnake Care


Tentacled Snake Care


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