Care & Breeding of the Golden Poison Frog, Phyllobates terribilis

The Golden Poison Frog of Colombia is probably the largest and certainly the most controversial dart frog in the world. Join us as we learn about this stunning amphibian and describe everything there is to know about its care and breeding in captivity.

Article, Photos and Videos by John Clare




Background

The Golden Poison Frog, scientific name Phyllobates terribilis, was first described to science in 1978 by Charles W. Myers, John W. Daly and Borys Malkin. While the species was new to science, the native Emberá Indians of the Cauca region of Colombia had made use of the frog’s powerful toxins for centuries.


Dr. Daly in particular was famous for studying the chemical compounds produced by organisms like frogs, known as natural products, for possible medicinal applications. To put this in context, most anti-cancer drugs used today are toxins whose dosage is tuned for maximum anti-cancer effect but minimal toxicity to the human body. Much of the inspiration for today’s top pharmaceutical drugs comes from chemical compounds discovered in nature. Every day, teams of chemists and biologists travel to remote parts of the world in search of plants and animals that may produce valuable chemical compounds new to science. These compounds could lead to potent non-addictive painkillers, more effective anti-cancer drugs, and possible cures for other terminal illnesses that claim so many human lives each year.



Photo: Young Phyllobates terribilis are nearly identical in appearance to adult P. aurotaenia. The gradual transition to the adult coloration is known as an ontogenetic change.


This medicinal potential is one of the reasons most trumpeted by environmental campaigners for the preservation of the world’s rainforests. If we destroy the animals and plants that produce these compounds before they are discovered, they will be lost to us forever.


The frogs of the genus Phyllobates are known to contain some of the most potent toxins in nature, and P. terribilis was found to possess enough of these powerful chemical compounds to make it, weight-for-weight, the most toxic animal on the planet. Each wild adult frog’s skin contains about 1.1 milligrams (that’s just 1/28,000th of an ounce) of the powerful toxin Batrachotoxin and related compounds. In theory this is enough to kill at least 6 people! The native Colombians made careful use of this toxicity for hunting by rubbing their blowgun darts along a frog’s back.



Photo: There are several variations of Phyllobates terribilis. This is the mint race or "morph".


While the toxin does not pass easily through human skin, any contact with an open wound or a mucous membrane (such as the lips or in the eye) could be very dangerous to a human being. The poison causes paralysis by locking the sodium ion channels, an integral part of the nervous system, in an open position. The body can no longer regulate muscle activity, including breathing, which leads to death.

Perhaps the most intriguing fact about this frog is that specimens that have been born in captivity do not contain these toxins! Studies indicate that the toxins must come from the prey that the frogs feed on in their native rainforest. Some possible sources include beetles and ants, but, to date, no one has found a proven origin of the toxins in wild specimens of the Golden Poison Frog. The frogs concentrate and sequester the toxins in glands on the surface of their skin. Why does the frog not die from the toxins? Simply put, it has special sodium ion channels that do not respond to the toxin, thus preventing it from suffering the paralyzing effects that the native Colombians rely on when hunting in the jungle. It must be said though that the natives rarely if ever use blowguns anymore, preferring to use firearms instead. Such is the march of progress.



Photo: Here are two subadults of the Orange morph of P. terribilis. Incidentally, the one on the left has a metabolic disorder.


From the hobbyist's point of view, the lack of these dangerous compounds in the skin of captive born specimens makes it a safe terrarium inhabitant because none of the foods eaten in captivity contain these toxins. However, this fact has not gotten in the way of the ignorance of some municipal governments: the Canadian provinces of British Columbia and Alberta recently banned these frogs and their close relatives.



Photo: The snake Liophis epinephelus, only known predator of the Golden Poison Frog, Phyllobates
terribilis. Photo ©2007 Twan Leenders, used with permission on FrogForum.


There is only one known predator of the Golden Poison Frog. The small, colorful snake Liophis epinephelus is at least partially immune to the toxins. It is capable of swallowing juvenile frogs but not the adults. This near-total invincibility has made the frogs incredibly bold. Wild specimens are often described as nearly indifferent to approach by human beings. Captive bred frogs retain this bold behavior despite a complete lack of Batrachotoxin. This makes the Golden Poison Frog one of the boldest species in the dart frog hobby.


Natural History

At nearly 5 cm long, Phyllobates terribilis is one of the largest poison frogs. A native of the Departmento Cauca in Colombia, the Golden Poison Frog is the most southerly member of the genus Phyllobates. It inhabits the lowland rainforest surrounding the rivers and streams that drain into the meandering Río Saija, very close to the Pacific Coast of the country. The rainforest here is among the wettest on the planet, receiving in the excess of 5 meters (more than 16 feet) of rain each year.



Image: Range map of Phyllobates terribilis (red area), P. bicolor (blue area), and P. aurotaenia (pink area). Original work (c)2011 John P. Clare. (Click the Map to Enlarge)


In the wild, these frogs are often found on moist slopes and hills in proximity to running water, a habitat combination that is common due to the nearby Cordillera Occidental mountain range. Myers et al. note that leaf litter is sparse in their preferred habitat (something to keep in mind when building a terrarium?).

Like other poison frogs, they are strictly diurnal. Toxicity and the resultant lack of predators make the frogs quite bold. They are frequently found sitting out in the open waiting for insect prey to pass by. As ambush predators, they wait for food to come to them, but are not afraid to pursue moving prey that has wandered into sight. The members of the genus Phyllobates are capable of tackling very large food items for their size, relative to other poison frogs. They will occasionally try to consume prey that is too large to swallow even with the aid of their front feet.



Photo: An adult Golden Poison Frog eating a fully grown waxworm.


Males have a loud warbling call (see video) that lasts about 6 seconds. Females are capable of short vocalization: receptive females will sometimes respond to a calling male with a short squawk. Courtship lasts about an hour. The male calls from in or near the intended laying site (usually a bower, and in the terrarium this often occurs in or near a coconut hut). Fertilization of eggs is external. Contrary to the belief of many hobbyists, the male first prepares the laying site with sperm, and the female lays her eggs shortly afterwards. The male generally leaves after depositing his sperm, or shortly after the female lays her eggs.


Click to view a Video: Golden Poison Frogs calling in a terrarium.


In my experience with this species in the terrarium, the female will sometimes linger in proximity to the eggs for hours or even a day after the eggs have been laid. On more than one occasion I have witnessed the mother keep one foot squarely on the egg mass or cover it completely as if guarding it. I am uncertain as to the motive, but I have noticed it can take several hours for the protective egg jelly to swell fully with absorbed water. I theorize that the female may be providing protection while the egg jelly reaches full size.



Photo: Freshly laid eggs of P. terribilis, in a petri dish.


There are no reliable numbers for clutch size in the wild, but terrarium clutches range from 8-30 eggs. Virtually all of the clutches I have observed number from 14-20 eggs each. More than one female may deposit eggs together at one time. Development takes between 10 and 14 days and is temperature dependent. At hatching, the tadpoles appear small and almost underdeveloped when compared to those of, for example, Dendrobates tinctorius. The male Golden Poison Frog returns to ferry the tadpoles on his back from the bower to a water source. This is the only parental care offered by the parents, though curiously, after metamorphosis of the youngsters, the adults ignore the bite-sized froglets as food.



Photo: The same eggs after 12 days of development. These tadpoles are nearly ready to hatch.


At 22°C (72°F), tadpoles reach the froglet stage in 50-60 days. Unlike the solidly colored adults, juveniles are black with two stripes of adult color running the length of the back at either side. Within a month or so the black coloration begins to change to the solid adult color. This is an ontogenetic color change – a normal developmental characteristic, common to several Phyllobates species.



Photo: Some variants of Phyllobates bicolor (such as this one) can be confused with P. terribilis. This has led to some hybrid lines in the hobby, and sometimes these are sold as purebred P. terribilis.


It should be noted that this species is not sympatric (does not occur in the wild together) with any other member of the Phyllobates genus, but it is capable of hybridizing with P. bicolor, and likely also with P. aurotaenia.


Suitability as Captives

New poison frog hobbyists who do their research often ask what is the best beginner’s species? Usual candidates include the Dyeing Poison Frog, Dendrobates tinctorius, the Green and Black Poison Frog, D. auratus, and the Bumblebee Poison Frog, D. leucomelas. Each has its merits, and all are considered relatively bold terrarium inhabitants. Surprisingly, the Golden Poison Frog is rarely considered by first-timers.



Photo: These tadpoles are far along in development.


And why not? It is not as commonly available as the other species. This may be attributed partly to the extended time it takes to reach breeding age, nearly 2 years. And aside from a small number of imports in the last 15 years, this species is solely available from other hobbyists, whereas the species mentioned earlier are regularly imported by wholesalers and specialist companies.

The Golden Poison Frog is perhaps the largest species available in the hobby. The only other rivals for this title are the larger races of D. tinctorius, D. auratus and D. leucomelas, and the uncommon Ameerega trivittata. While these can often match the snout-to-vent length of P. terribilis, they cannot match its robust build and sheer girth. Unlike most other dart frogs, P. terribilis is a gape-limited predator. This means it can consume any prey provided it can fit into its mouth. Dendrobates tinctorius has difficulty tackling food items much larger than Drosophila hydei fruit flies. In terms of boldness, adult Terribilis will often jump at the feeding container before the food has even been offered and they will beg at the terrarium glass when you pass by. They are so defiantly bold that if you stick your hands in the terrarium they will often remain stock still unless you touch them.

Their ability to eat larger than normal food items can be a life saving trait if your fruit fly cultures fail. They will readily consume crickets, wax worms and mealworms, all commonly available at pet stores.



Photo: Golden Poison Frogs are generally considered one of the most terrestrial (ground-living) species of dart frog. As you can see from this photo, no one told the frogs!


Most dart frogs prefer a temperature range between 21 and 27°C (70-80°F) during the day, but P. terribilis can tolerate lower temperatures than most other species, right down to about 16°C (60°F). However, temperatures over 27 are particularly dangerous to this species.

Their unequaled bold nature is likely due to the toxicity of the frog in the wild – if nothing can eat you, why be afraid? Fortunately, captive bred specimens completely lack these toxins but retain their bold character.

The only minor downside to this species is that when they are not eating or breeding they often sit very still for long periods.

In summary, Terribilis has no significant disadvantages when compared to other species of poison frog, and several winning characteristics not found in the others.


Morphs in Captivity

As you've seen from the photos of the mint and orange morphs earlier in this article, and the many photos of the yellow morph, there are 3 morphs in captivity. Due to the small range of the species, and the descriptive account of finding different morphs not far from each other, it is unlikely that there are significant genetic differences.

In the hobby, there is anecdotal evidence that the mint morph may be slightly larger than the other two morphs. Due to the small founding stock and the lack of precise measurements of similarly aged frogs that have been raised in analogous conditions, it is difficult to make any certain conclusions regarding size differences.


General Captive Care

These frogs are only available as captive bred animals. The wild frogs are protected from export, and all of the specimens found in captivity in the US and Europe are descended from what were legally or illegally exported frogs. British Colombia and Alberta in Canada have banned the possession of this species on the misinformed basis that captive specimens are toxic. Elsewhere in North America these frogs are readily available in the dart frog hobby and from many dart frog vendors.

The mint morph is the most commonly available and usually the cheapest. The orange and yellow morphs are a little less common and consequently they are a little more expensive. You shouldn’t have to pay more than $90 for a juvenile frog of any race. When choosing a frog in person, look for a frog with a well-fed belly, bright eyes, secretion-free skin, and a bold nature. If possible, ask the vendor to feed the frog in front of you. A healthy terribilis will be more concerned with chasing food than with you watching.

Young terribilis are a dark brown or black frog with stripes of adult color running from either side of the head along the upper edges of the back. They also possess spotted or patchy legs. Juveniles do not develop the solid coloration of adults until they are a few months old.


Housing and Setup

These large bold frogs are very terrestrial, and while they do climb on occasion, they are most commonly seen on the floor of the terrarium, perhaps more so than any other dart frog. With that in mind, it is important to choose a terrarium of dimensions that provide a large amount of floor space per frog. For an adult terribilis, I consider 100 square inches to be the absolute minimum per frog. This would allow you to keep 3 adults comfortably in a 20 gallon long aquarium (length x width dimensions 30 x 12 inches). I maintain 5 adults in a 40 gallon “breeder”, which has length x width dimensions of 36 x 18 inches. Juveniles can be kept in much smaller accommodations while they grow.

An all glass aquarium makes a relatively cheap terrarium for these frogs. Custom made acrylic terrariums can be purchased from specialist vendors, and the big name terrariums sold commonly at reptile shows can be readily converted into dart frog friendly terrariums.

A secure fitting lid and the ability to maintain humidity are necessary traits for any terrarium. Humidity can be maintained with daily misting using a hand mister. Distilled water is ideal for this purpose because it will leave virtually no mineral deposits on the glass, which might obscure your view of the frogs. If you have more than one terrarium, or you want to make a striking display terrarium, you should consider a commercial misting system. They are not cheap, but it’s one less chore to perform and it insures a relatively constant level of humidity, whether you’re around or not.

My first step for a new terrarium, particularly when it’s meant as a display terrarium, is to make a drawing of how I want to landscape it. Typically, I will begin by constructing a background for the terrarium. The easiest approach is to use aquarium silicone to glue tree fern fiber panels to the back wall. I fill in the gaps with terrarium soil (more on substrate later). These panels are excellent for planting bromeliads and climbing plants, and mosses usually begin to grow on the panels in a few months. You can now buy rectangular corkwood panels that are designed specifically as terrarium backgrounds. They can be attached using aquarium silicone. Be sure to seal any holes and gaps that might allow a frog to enter and become trapped. A third option for background material is to spray a layer of expanding polyurethane foam on the aquarium wall. When cured, this is then covered with silicone and then substrate material, such as coconut fiber, is pressed into the still wet silicone. A fourth option is to mix a clay recipe that can be pasted on to the aquarium glass.

After the background has been set up and cured, I then proceed to construct the drainage layer. This is where excess moisture will end up, away from the substrate, which can rot and become anaerobic if water logged. In large terrariums I like to include a pond area. This is readily accomplished by leaving a space in the drainage layer in a corner of the terrarium. The drainage layer itself should consist of at least 2 inches of a low density material like hydroton/LECA, or the plastic egg crate sold as a diffuser for fluorescent lighting. There are commercial alternatives available from some dart frog vendors. If money is a factor, aquarium gravel can be used, but this can be extremely weighty, an important property to minimize if you think you might ever have to move the terrarium.

The drainage layer is covered with a layer of fine fiber glass mesh, such as window screen, in order to prevent particles of substrate from entering the drainage layer. The substrate itself should be at least 1 inch thick. Slopes and valleys can be constructed by varying the substrate depth. Substrate choices should be free of artificial additives and perlite. Good options include aquatic soil products, ABG mix developed by Amphibian Ark’s Ron Gagliardo, and coconut husk mixed with coconut fiber. In recent years many hobbyists have made their own substrate mixture with a large component of clay, as this seems to be closer to the natural substrate of the rain forest.

I like to cover the substrate with leaves that last a long time under humid conditions. Suitable species include Live Oak, Magnolia (southern is better), Sea Grape, Pin Oak, and Indian Almond. Thicker leaves generally last longer, but you can use the leaves of more northerly species of tree, just don’t expect them to last long.

Landscaping is totally up to you. Large pieces of driftwood can make striking center pieces, as can large pieces of cork bark made to look like tree trunks. These make good sites for bromeliads and other epiphytic plants. Be sure to use a wood that can stand up to the humid conditions of dart frog terrarium without molding frequently or rotting away. Good choices include Ghostwood, Mopani, Malaysian Driftwood, and Manzanita. Avoid the grape wood commonly sold for reptile terrariums because it never really ceases to mold.

Most terrestrial dart frogs lay their eggs in bowers. It’s often wise to include these in your landscaping design in advance. The favorite choice of most dart froggers is a half-coconut shell with a plastic petri dish underneath. You can also choose pieces of wood based on the hides or overhangs they provide, and if you are using a foam-based background, you can carve caves and shelves into it to serve the same purpose, prior to covering the foam with silicone and coconut fiber.

At this point your thoughts should turn to planting. Most terrarium plants are at least partially ephiphytic (they get their nutrients from the air). This includes the “tank” bromliads such as Neoregilia, and Tilandsia. When choosing bromeliads, be sure to select those that are small enough for the terrarium. Many of the bromeliads available at hardware stores and garden centers are youngsters of large species, or they have been forced to bloom at a smaller size than their true growth potential. Consult a dart frog vendor for specific recommendations, but a few suitably sized varieties include the following Neoregilias: “Dartanion”, “Ampulacea Red”, “June Night”, “Ritzy Red”, “Ariel”, “Shamrock”, “Fireball”, “Zoe”, and “Wee Willy”.

Most other tropical plants can be planted in the substrate layer. Popular choices include tropical Begonias, Aroids (e.g. Syngonium sp., Philodendron sp. and even Pothos), Ficus sp., Pepperomia sp., Hoya sp., tropical mosses, and even aquatic plants such as Java Moss (Vesicularia dubyana) and Riccia fluitans. If kept moist and given plenty of light, Riccia can form a beautiful green carpet in the terrarium, and there’s nothing as striking as a bright golden yellow terribilis standing on a field of Riccia. Many of the plants mentioned earlier are available at the hardware store as shade loving house plants. Be sure to rinse these plants thoroughly to remove any pesticide residue before placing them in the terrarium.

If you wish to grow plants successfully, an artificial lighting solution will be required. The fluorescent lighting fixtures sold for aquariums are often the most convenient solution. Be sure to choose the “freshwater” variant because these bulbs will be in the proper color temperature range for tropical plant growth, namely 5000-10000 Kelvin. I like the color and results from bulbs that are 6500 or 6700 K.

Terribilis are one of the more cold tolerant and heat intolerant dart frog species. A daytime range of 65-75 °F is appropriate, followed by a slight drop at night to as low as 60 °F. This species does not tolerate temperatures in excess of 80 °F. If you cannot maintain temperatures below this maximum, consider acquiring an air conditioner or keeping the frogs in a basement; it is generally easier to heat a terrarium than to keep it cool. My favorite heating solution, particularly for a large terrarium, is a heating cable. Traditionally these are sold for growing plants, but manufacturers are beginning to market them to terrarium keepers. Be sure to get a waterproof model and an appropriate thermostat. These systems provide a gentle, near-constant heat. If you have a large drainage area that always contains over an inch of water, you might consider an aquarium heater. These will heat the water directly, but this will also pass on some heat to the air and substrate.

Terrarium maintenance each month should be minimal. Wipe the glass with paper towel dipped in distilled water. Trim plants as they start to get out of control and obscure your view. Fluorescent bulbs lose intensity with age and are best replaced about once per year. You should almost never have to change the substrate. Most dart frog terrariums that are set up after advanced planning can go at least 3 years before they need to be re-constructed.


Feeding

Keeping dart frogs can be a challenge for the first time keeper. Thankfully, feeding them is a straightforward matter. Virtually all dart frog hobbyists culture their own fruit flies. Fruit fly culturing supplies are available at reptile shows and from online vendors. Cultured fruit flies are flightless or wingless mutations of the species Drosophila melanogaster (a small species) and D. hydei (a large species). D. hydei are the staple of choice for larger dart frogs like terribilis. In fact, adult terribilis will often ignore D. melanogaster due to their small size.

Fruit flies in and of themselves are not a complete food for dart frogs. They require augmentation using commercial vitamin and mineral supplements. I dust my fruit flies at every feeding, rotating through 3 well known supplements, two of which are different brands of general vitamin and mineral supplement, and the third is a calcium supplement with Vitamin-D3.

Adult terribilis should be fed every 2-3 days with at least 20 D. hydei per frog. Youngsters and froglets should be fed on a daily schedule. In my experience, terribilis froglets can take the larger fruit flies from when they first begin to eat after metamorphosis. Adult terribilis that have been well fed can safely go a week without feeding. This is not possible for youngsters, so if you must go on vacation, insure you have trained a friend or neighbor in how to feed your frogs.


Much of the necessity for supplements is due to a lack of variety of foods. However, often this can’t be helped when it comes to sourcing a small and reliable food source for our dart frogs. Captive cultured crickets are a handy alternative that can add some variety to the diet of terribilis. Indeed, adult frogs of this species are capable of tackling near full-grown crickets with ease. Youngsters relish pinhead/hatchling crickets. Some keepers mistakenly believe that crickets and other large prey items are essential to keep terribilis successfully. This is not the case. However, there is anecdotal evidence that food variety may stimulate breeding behavior in this frog, and a varied diet cannot be a bad thing.

Terribilis are capable of taking large food items, and they enjoy treat foods like wax worms and firebrats. An adult terribilis can easily swallow several mature wax worms. Wax worms are a high fat food and should only be fed on rare occasions. I like to give my adults a feeding of wax worms once or twice each month.


Breeding

If both sexes are present, healthy mature terribilis will usually begin to breed by the age of 18 months. Some do not breed successfully for more than 2 years. No distinct breeding stimulus should be necessary because these frogs are from tropical latitudes and breed naturally throughout much of the year.

The time taken to reach maturity makes them one of the longer term investments for the dart frog breeder. Eggs are laid in a bower, such as in a petri dish under a coconut hut, or on the leaf of a plant in the Aroid family. Clutches are large, sometimes numbering in the 20s or even in the 30s. The eggs hatch in about 14 days. If left in the terrarium, father will carry the hatchlings individually or in “tadpole packs” on his back to the nearest water source. An in-terrarium pond is great for this purpose. Generally, only about 50% of the eggs make it to hatching.

Tadpoles are gregarious and do not secrete large amounts of growth-inhibiting hormone like Dendrobates tinctorius tadpoles. They should be kept at similar temperatures to the adults during the daytime. If raising the tadpoles outside the terrarium, be sure to treat tap water with aquarium dechlorinator, and also administer a tannin-rich additive such as “Blackwater Extract” to mimic natural water conditions.

A good fish food pellet should be the staple diet of tadpoles. I like to alternate between a fish food pellet containing some vegetable matter as well as the normal fishmeal component, and a pellet intended for more carnivorous fish.

Tadpoles should begin to metamorphose in about 3 months or sometimes a little longer. Be sure to provide an easy escape from the water so that the froglets do not drown. They will not feed while they are resorbing their tails and for a day or two afterwards. Since the froglets can usually take Drosophila hydei from the start, terribilis are probably the easiest of all dart frogs to raise.


Closely Related Species

Phyllobates bicolor, Phyllobates aurotaeniea, and P. vittatus require similar care and conditions to the Golden Poison Frog. Please do not mix species because it is not unheard of for Phyllobates terribilis and P. bicolor to consume smaller frogs!


Conclusion

While the Golden Poison Dart Frog may be the most infamous of amphibians, it is perhaps the boldest and hardiest dart frog in captivity. The striking coloration and ease of feeding should put this species at the top of the list for the first time dart frogger, as well as the more experienced enthusiast.

For more photos of this species, check out this photo album at FrogForum.net: http://www.frogforum.net/members/joh...1-onwards.html

Article is ©2013 Dr. John P. Clare and FrogForum.net. All rights reserved. A portion of this article appeared in the 2011-2012 Annual Edition of Reptiles Magazine (USA). This article may not be reproduced or published in part or in whole without written permission from the author.

Comments, suggestions and criticism welcomed!