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Best Tadpole Foods (Based on my Experiences) – Seeking Additional Suggestions

Frank Indiviglio — Wed, 20 Feb 2013 21:53:01 +0000

Hello, Frank Indiviglio here. Breeding frogs and rearing tadpoles is one of the most enjoyable aspects of our hobby, and becoming ever more important to the survival of many species. In the course of working with numerous species at home and in zoos, I’ve compiled a list of commercial foods that have proven especially useful as tadpole foods. The variety of new food items that have appeared and the many frog species that have been recently bred by hobbyists have convinced me that it’s time to reach out see what new “wonder products” or ideas folks have tried. I have, therefore, highlighted some of the foods I’ve come to rely on, and would greatly appreciate hearing of your experiences with them and others. Thank you.

The Amazing Specialists

While the tadpoles of many commonly bred frogs (i.e. White’s Treefrog, Litoria caerulea) are omnivorous and take a variety of foods, others are specialists and will not survive unless their exacting requirements are met. The tadpoles of African Clawed Frogs, Xenopus laevis and Malayan Leaf Frogs, Megophrys nasuta, for example, are filter feeders, while those of the African Bullfrog, Pyxicephalus adspersus, are as carnivorous as their pugnacious parents. Poison Frog tadpoles of several species feed upon unfertilized eggs deposited by their mother, Goliath Frog, Conraua goliath, tadpoles consume a single species of algae, Fringe-Limbed Treefrog (Ecnomiohyla rabborum) tadpoles eat their father’s skin, Brown Leaping Frog (Indirana semipalmata) tadpoles gnaw on wood (high up in trees!) …the list is fascinating. Please post below if you would like information on these or other species.

General Considerations

In general, omnivorous tadpoles should be provided with as many of the following foods as is practical. As we do not know much about the natural diets of filter-feeding tadpoles, they too should be given a wide variety of finely-ground commercial foods. Horned Frog (Ceratophrys spp.) and other carnivorous tadpoles do best when high protein foods such as freeze-dried bloodworms, shrimp and pre-killed minnows are added to a Reptomin-based diet.

I’ve found that nearly all tadpoles relish kale, and experience has shown it to be a very beneficial addition to their diet. I have, as an experiment, successfully raised American Bullfrog, Lithobates catesbeianus, and Green-and-Gold Bellfrog, Litoria aurea, tadpoles on a diet comprised solely of kale and tropical fish flakes. Soak kale in hot water for 10 minutes or so before using, so as to improve its digestibility.

Reptomin Floating Food Sticks (Tetrafauna)

If I had to choose a single food that fits the needs of most tadpoles, I’d go with Reptomin Floating Food Sticks, which I have relied upon in zoos and my own collection for decades. I’ve had excellent results using this product as 50-75% of the diets of a variety of tadpoles, including American and African Bullfrogs, Green Frogs, European Edible Frogs, American Toads, Wallace’s Flying Frogs, Australian Bell Frogs and Ornate Horned Frogs.

Reptomin contains a variety of animal and plant ingredients, including shrimp, algae and fish meal, wheat, corn and potato. The floating sticks soften quickly, but not so much as to become unavailable to larger tadpoles, sink after becoming water-logged, and can also be ground up and offered to filter feeders. Reptomin is also an excellent food for many adult aquatic frogs, newts, turtles, and invertebrates…I even use it to gut load feeder crickets and roaches. It has crossed over from the pet trade and is now a staple in zoos worldwide. Please see this article for further information on this valuable food item.

Canned and Sun-Dried Freshwater Shrimp (ZooMed)

Shrimp are very numerous in many freshwater environments, and likely play a role in tadpole diets. While marine shrimps and krill have long been available as tropical fish food, freshwater species are difficult to find. I was, therefore, pleased to learn that Zoo Med is now using a fresh water shrimp, Macrobrachium nipponense, in its Canned Shrimp and Sun Dried Red Shrimp products.

Excellent as a high-protein addition to the diets of most tadpoles and very important for carnivorous species, both products are easy to use. Canned Shrimp, being quite “meaty”, is ideal for the voracious tadpoles of African Bullfrogs, Horned Frogs and similar species. Sun Dried Shrimp can be crushed to meet the needs of smaller tadpoles and filter feeders. You can read more about these products here.

Tropical Flakes Fish Food (TetraMin)

As with ReptoMin, tropical fish flakes are highly nutritious and an ideal food for a wide variety of tadpoles. I’ve relied most heavily upon TetraMin’s original Tropical Flakes, and cannot recall any species that has refused it. Developed in 1950, this product can be ground into a powder fine enough even for the tiny filter feeding tadpoles of the Dwarf African Clawed Frog, Hymenochirus curpites, but is also taken by American Bullfrogs and other large species. I also provide it to feeder insects, snails, millipedes, and shrimp (and fish!).

Other flake foods developed for fishes with specific dietary needs (i.e. algae feeders, Cichlids) may also be used to add variety to tadpole diets.

Spirulina Discs (Wardley)

Wardley Spirulina Discs contain blue algae meal, spinach powder and other plant-based ingredients important to the health of nearly all tadpoles. As carnivorous species likely consume some plant material in the wild, I add Algae Discs to both their diets and those of omnivorous/herbivorous tadpoles. Many other foods formulated for plant-eating fishes are also useful tadpole foods.

Earthworm Fish Food Flakes (Zoo Med)

I’ve long championed earthworms as a herp food, and so was interested in trying out Zoo Med’s new Earthworm Flakes. The flakes also contain salmon, shrimp meal and plankton, and are readily consumed by most tadpoles. Further thoughts on this exciting new product can be found here.

Repto Treat Delica Bloodworms (TetraFauna)

Bloodworms, the larvae of midges (or “gnats”, Family Chironomidae), are one of the few small insects available to tadpole keepers.

TetraFauna’s Repto Treat supplies bloodworms encased within a vitamin-enriched gel.

Bloodworms and other aquatic insects form the basis of the food chain in many tadpole habitats, and are almost certainly an important food item. Also, tadpoles consuming Repto Treat will be eating the entire organism, an important consideration if research on adult amphibians is any guide. You can read more about the use of bloodworms as an amphibian food here.

There are many other tadpole food options…please post your ideas and experiences below, and I’ll be sure to share them with my readers and colleagues.

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 Indiviglio

Amphibian Declines – Pollution Worsens Disease and Parasite Attacks

Frank Indiviglio — Mon, 22 Oct 2012 16:00:13 +0000

Hello, Frank Indiviglio here. In 1990, the IUCN’s Declining Amphibian Populations Task Force, to which I belonged, was one of the few large scale efforts addressing what is now known as the “Disappearing Amphibian Crisis”. Today, with legions of biologists and hobbyists at work on the problem, we still do not fully understand why nearly 200 species have become extinct in the last 20 years – a rate 200x that of what might be “expected”. But we do have some insights, one of which was highlighted in a recent journal article (Philosophical Transactions of the Royal Society (Biology) . It appears that stress, much of which is in response to what we are doing to amphibian habitats, is worsening the effects of normal pathogens and diseases.

Parasites and Insecticides: a Confusing Scenario

As the reality of worldwide amphibian declines became apparent, herpetologists and private citizens began noticing increasing numbers of deformed and dead frogs. In 1995, school children in Minnesota made headlines when they found dozens of deformed frogs in a local pond. Since several chemicals are known to cause growth abnormalities, researchers began focusing on pollutants. At the Bronx Zoo, I worked with a veterinarian who studied African Clawed Frogs, and was amazed to see ovaries develop in males that had been exposed to Atrazine (a common insecticide).

But pollutants turned out not to be the whole story…a parasite also played a role. The creature involved needs to infect both a frog and a wading bird in order to complete its life cycle. Amazingly, it lives within a tadpole for a time and “re-programs” the development of the hind legs as metamorphosis occurs. The newly-transformed frog develops extra rear legs and, unable to jump very well, is likely to be caught by a heron – just as the parasite “intended”!

Actually, many parasites cause incredible changes in their hosts’ behaviors – one “directs” an ant to climb into the canopy and raise its now red-colored abdomen skyward in imitation of a tasty berry (so that it is eaten by the next essential host, a bird), another causes the host spider to build a silken shelter before dying, so that the parasite has a safe place in which to emerge, and so on…

Are Pathogens Changing?

Amphibians evolved some 300-400 million years ago, long before the dinosaurs, and they’ve likely been battling parasites similar to those described above for much of that time. The same can be said of other fungi, bacteria and viruses that attack them.

Yet it seems that certain pathogens and diseases, despite being around for centuries, are now causing unprecedented amphibian population declines and extinctions. For example, Chytrid fungus, first identified as a serious threat in 1999, may be responsible for the disappearance of nearly 200 species. Although termed an “emerging disease”, it was likely present all along, but is now spreading more rapidly, and having a more devastating effect on its victims. This trend is seen among frogs worldwide (salamanders and caecilians are not as well-studied) – many pathogens are more common now than in years past, are spreading to new habitats, and are causing unusually high mortality rates.

The Role of Stress

According to the article referenced above, multiple stresses may be weakening amphibian immune systems, rendering them unable to battle common illnesses. We see this in captivity all the time – animals that are assailed by inappropriate temperatures, hostile tank-mates or poor diets often fall victim to parasites and diseases that would have been handled by the immune system had conditions been ideal.

One stress factor can depress the immune system (in zoos, birds moved to a new exhibit often succumb to Aspergillosus infections, an ever-present fungus that typically causes no problems). Currently, many amphibians are exposed to pollution, climate change, introduced species, habitat fragmentation and other stressors simultaneously. Small wonder that at least 2,500 species are believed to be in decline.

Permeable skins that allow for the passage of harmful chemicals, and the typical need for two distinct habitats, predispose amphibians to difficulties when environmental changes occur. However, there is evidence that similar processes are at work among other groups as well (please see this article on snake declines).

What’s Next…What Can I Do?

Please be on the alert for deformed amphibians and signs of population declines, and post your observations here. I can help you to get the information to organizations that can put it to good use. Also, a colleague of mine is now involved in Amphibian Ark, a fine conservation group which can provide guidance if need be.

Please see the articles linked below for information on IUCN surveys and other efforts that utilize volunteers.

Please also post your questions and comments below…I’ll be sure to respond quickly.

Thanks, until next time,

Frank Indiviglio

Chorus Frogs and Chytrid Bacteria – a Look at the Confusing new Reports

Frank Indiviglio — Tue, 20 Mar 2012 14:57:34 +0000

Hello, Frank Indiviglio here. Are Pacific Chorus Frogs, Pseudacris regilla, driving other amphibians to extinction? A recent study revealed that the tiny frogs often carry a fungus (Batrachochytrium dendrobatidis, or Chytrid) that has been implicated in the extinction of 200+ amphibian species. Chorus Frogs seem largely immune to the disease, but may spread it to other species that share their habitat, including the endangered Mountain Yellow-Legged Frog, Rana mucosa. However, I believe there is more to the story…

Resilient Chytrid Carriers

Researchers from San Francisco State University and the San Diego Zoo have confirmed high levels of Chytrid fungus among Pacific Chorus Frogs in California’s Sierra Nevada Mountains. Unlike many amphibians, Chorus Frogs seem relatively unaffected by the fungus.

As Pacific Chorus Frogs have a huge natural range and readily colonize new habitats, it is feared that they will spread the highly contagious disease to other amphibians. In fact, Chorus frogs often live near Yellow-Legged Frogs, an endangered species that has suffered a 90% decline in numbers in recent years.

A Protective Bacterium

The study also indicates that bacteria on the skin of Chorus Frogs may help them to survive Chytrid infections. Upon reading this, I recalled earlier studies of a similar nature, and checked into the topic.

It seems that Chytrid-protective bacteria have also been isolated from the skin of Red-Backed Salamanders, Plethodon cinereus and Mountain Yellow-Legged Frogs (the endangered species mentioned above). I do not know whether the bacterium found on these 2 species – Janthinobacterium lividum – is the one that colonizes Chorus Frog skin.

An article in Scientific American (July 12, 2010), reported that J. lividum can be cultured in the lab, and that amphibians with the highest J. lividum populations on their skin had the greatest immunity to Chytrid infection. Wild Mountain Yellow-Legged Frogs were to be inoculated with the bacterium to see if immunities would develop. I’m looking into the status of this project, and will report any new findings in the future. Please see the article below for additional information.

Researchers in Central America are also studying frogs that were found alive after Chytrid swept through their habitats. Perhaps these rare survivors hold the key to understanding this devastating disease phenomenon.

Don’t Blame Chorus Frogs!

Before we cast too much “blame” on Pacific Chorus Frogs (African Clawed Frogs have been cast as Anuran “Typhoid Mary’s” as well), it should be noted that a host of other factors are likely at work. Pollution, climate change, habitat alteration and the like can weaken immune systems, rendering a species susceptible to Chytrid attack.

In fact, Yellow Legged Frogs are exposed to pollution, climate change and introduced predators (trout)…perhaps this partially explains why protective skin bacteria seem not to affect their survival when exposed to Chytrid.

Other Chytrid Concerns: Amphibians as Food and Bait

Three to four billion frogs are collected from the wild each year for the food trade…many more are likely not recorded. The USA, not a major consumer, imports 4.4 million pounds of live frogs annually. Shipping live frogs to foreign countries has been tied to Chytrid outbreaks in areas that had formerly been free of the deadly amphibian disease.

I’ve long been involved in frog confiscations in NYC and am convinced that the trade is adding to the problems already faced by native species; please see this article to learn how you can help.

While Eastern Tiger Salamanders are protected in several states, the larvae of western races are widely used as fishing bait (hooked while alive, no less!). Researchers from the National Science Foundation have documented high levels of Chytrid infection and Ranaviruses in bait trade salamanders.

Chytrid is a complex problem, but bait and food trade issues seem fairly straightforward…yet little is being done. Please see this article to learn how to register your opposition to the use of amphibians as fishing bait.

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 Indiviglio

Spotted Salamanders Adapt to Salt and other Roadside Toxins

Frank Indiviglio — Wed, 14 Mar 2012 14:23:12 +0000

Hello, Frank Indiviglio here. Early spring is a favorite time for amphibian enthusiasts. Here in the northeastern USA, a spectacular event is unfolding, as Wood Frogs, Tiger and Spotted Salamanders, Spring Peepers and others head en masse for their breeding ponds. I’ve been visiting one pond, first shown to me by herpetologist John Behler, for nearly 30 years. When luck is with me, I can see 3 amphibian species, along with fairy shrimp and other interesting creatures, in a single evening (please see article below).

The small vernal (temporary) pools used by many amphibians are fragile habitats, and quickly spoiled by pollutants; that many are near roads worsens the situation. With their highly-permeable skins, amphibians are especially sensitive to changes in water quality. The recent finding that Spotted Salamanders (Ambystoma maculatum) may be evolving defenses against roadside toxins is a rare light at the end of the rather dismal “amphibian conservation” tunnel.

“Salt Water” Salamanders

Yale University researchers report (Science Papers, January, 2012) that toxins carried into ponds via road runoff may be spurring the rapid evolution of defensive adaptations in Spotted Salamanders. Due to road salting, the salinity of roadside ponds can be 70 times that of nearby woodland ponds; a variety of other toxins are also commonly present.

Life in ponds subjected to road runoff is difficult. Salamander larvae living in roadside ponds suffer higher mortality (44% vs. 13%) and an increased number of skeletal defects than do larvae from ponds located away from roads. Also, metamorphosis is delayed. This is particularly troublesome, as vernal pools dry up during the summer – larvae that have not transformed by that time perish.

Only the Strong Survive…

However, those salamanders that have somehow adapted to these harsh conditions seem to gain a survival advantage over those hailing from “natural”, or un-polluted, ponds. Their larvae out-survive other larvae when both are reared together in roadside water.

More surprising than this, however, is the fact that roadside pond larvae also do better than natural pond larvae when reared in unpolluted water. The mechanics are not yet understood, but some survival advantage seems to carry over and remain useful even in non-toxic environments.

This finding is the first known example of a vertebrate evolving in response to roadside toxins. However, only cautious optimism is in order, as each environment and species represents a different scenario…and far more creatures are likely to succumb rather than adapt to pollution.

Please also post your questions and comments below…I’ll be sure to respond quickly.

Thanks, until next time,

Frank Indiviglio

Amphibian Medicine – Cold “Resurrects” Hellbender and Sick Frogs

Frank Indiviglio — Thu, 23 Feb 2012 13:01:21 +0000

Hello, Frank Indiviglio here. During my years with the Bronx Zoo, I have twice observed cold temperatures to revive salamanders (a Hellbender and a Greater Siren, please see photo) that seemed, by external appearances, to be quite dead. A recent paper caused me to think back on these events, and to other examples of low temperatures being used to “treat” ailing Axolotls, Leopard Frogs and other amphibians …I would greatly appreciate your own observations and thoughts on this topic.

Cold Tolerant Amphibians

Many amphibians are well-adapted to surprisingly low temperatures. On Long Island, NY, Eastern Tiger Salamanders may migrate to breeding ponds in February, and Spotted and Alpine Salamanders will cross snow for the same purpose. Wood Frogs occur within the Arctic Circle, and I’ve found Gray Tree Frogs hibernating beneath a mere 2” of leaf litter in NYC. Several Fire Salamanders under my care remained active at 38 F.

Early Experience with Cold Treatments

Back when I began keeping amphibians, little was known about treating their ailments. As an eager 12-year-old “working” (largely without pay, other than an occasional slice of pizza!) for an animal importer in NYC, I was frustrated by the losses common in shipments of newts and frogs.

Calls to the Bronx Zoo and American Museum of Natural History were (uncharacteristically) not very productive. I then contacted Wards and Carolina Biological, whose biological supply catalogs I had drooled over for years. A kindly soul took the time to put me in touch with a lab that housed Leopard Frogs. I learned that when bacterial diseases (“red leg”) struck, the frogs were refrigerated at 36-40 F for varying periods. Chilled frogs often survived, while those kept a room temperature perished. Neither my boss nor my mother appreciated the sickly amphibians stored in their refrigerators that followed this revelation, but both showed patience that I remain grateful for today!

Recent Experiences

The salamanders I mentioned as being “brought back to life” by the cold certainly did appear to be dead. I believe the Hellbender went on to live for years after its “near-death experience”.

Other interesting experiences have involved Mexican Axolotls. An individual in my collection became bloated and was unable to submerge. A veterinarian who worked with me at the Bronx Zoo prescribed Itraconizole and other medications, but the infection proved resistant to all. I refrigerated the animal at 40 F, whereupon the swelling abated. I removed her for feeding once weekly, and left her out for 2 days following. The swelling (gas from bacterial action) would recur after 2 days at room temperature. A friend maintained an Axolotl under similar conditions for several months.

I also had some success while treating 100+ American Bullfrog tadpoles that had been stranded when their pond was drained. Although most suffered severe abrasions, many recovered after being held at 40 F for several weeks. They were initially treated with Methylene Blue as well; please see article below.

Conflicting Results: Cold Hinders Recovery

However, cool temperatures are not the answer to every amphibian health issue. My veterinarian co-workers sometimes suggest keeping medicated animals at optimal temperatures for normal activity, the theory being that the immune system will function best under these conditions. There may be a fine line, especially where cold-adapted species are concerned. Perhaps certain micro-organisms do not cope well with low temperatures, and can be more easily killed by amphibian immune systems when the hosts are chilled.

In one study, mortalities increased when Australian Barred Frogs (Mixophys fasciolatus) suffering from Chytridiomycosis were chilled to 62 F. And keeping American Bullfrogs at 38 F was found not to affect the survival of 4 species of harmful bacteria, but it did impede the frogs’ abilities to fight off infections. Each species and health problem must be evaluated individually…please write in to discuss specific situations.

Observation: Snapping Turtle in February

Slightly off-topic: just last week (February 17, 2012) I came across a large male Common Snapping Turtle who was out and about in a small woodland pool in northern New Jersey. While this species is perhaps the most cold-tolerant of all turtles, I’ve not seen one active this early in the year. As you can see from the photo, he tried to respond to the indignity of being photographed in true snapper fashion, but was too slow to scare my intrepid little hiking partner (please see photo).

Please also post your questions and comments below…I’ll be sure to respond quickly.

Thanks, until next time,

Frank Indiviglio

World’s Smallest Frogs Added to 2011’s List of Newly-Discovered Amphibians

Frank Indiviglio — Mon, 02 Jan 2012 20:55:03 +0000

Hello, Frank Indiviglio here. Two frog species recently discovered in southeastern New Guinea are smaller than any other 4-legged vertebrate. Within their pea-sized bodies, they pack a brain, lungs, heart, digestive system and most of the other organs that people have…simply astounding!

Tiny Frogs and Fish

The frogs, Paedophryne dekot and P. verrucosa, were collected several years ago, but were only described as new species this year (please see ZooKeys article). Among all the world’s vertebrates, only a single fish, a Southeast Asian relative of the carp (see amazing photo here) is smaller – and the new frogs exceed it in size by only 0.1 mm! Another contender for the title, a leaf-litter frog from Cuba (please see photo of striped frog), is only a tiny bit larger.

Minute Predators and Prey

New Guinea’s new frogs, which have yet to be given a common name, measure 8-9 mm., or 0.3 inches, in length. They inhabit the leaf litter of tropical rainforests, where they are likely on the menu of predators ranging from spiders to small birds. Females produce 2 eggs, but the details of their reproductive biology are unknown.

I’m looking forward to reading more about their lifestyles, especially their diet. Some years ago, I cared for a colony of tiny Kihansi Spray Toads (please see article below) at the Bronx Zoo. They gave birth to live froglets, which were the smallest amphibians I’d ever seen. Some could not even handle a pinhead cricket, and had trouble “wrestling-down” springtails! The new Paedophryne frogs must hunt some very tiny leaf-litter invertebrates.

Diversity Hotspots

New Guinea has provided a treasure-trove of new species in recent years, with over 1,000 new animals and plants – or over 2 each week – described there since 1998. Indonesia is also offering surprises…I’ve had the pleasure of working with some of these, including the gorgeous Blue Tree Monitor (Varanus macraei); please see article below for more info.

India has also made frog headlines, with at least 25 new species described, and several pleasant re-discoveries of frogs believed to have become extinct. They are a wonderfully-bizarre group of amphibians, as is indicated by their fanciful common names – Meowing Night Frog, Elegant Tropical Frog, Feisty Frog and so on. Please see the article below for photos of India’s unique new frogs.

Please also post your questions and comments below…I’ll be sure to respond quickly.

Thanks, until next time,

Frank Indiviglio

Multicolored Rainbow Toad, “Missing” since 1924, is Found in Borneo

Frank Indiviglio — Wed, 14 Sep 2011 19:16:53 +0000

Hello, Frank Indiviglio here. The Borneo Rainbow or Sambas Stream Toad, Ansonia latidisca, is known only from drawings made by its discoverer, and has not been seen in 87 years. Extensive development of its only known habitat has long raised fears of its extinction. This month (July, 2011), however, it became the second of the world’s “Ten Most Wanted” amphibians to be rediscovered.

“Ten Most Wanted”

In 2010, Conservation International launched the Global Search for Lost Amphibians (please see article below). Since then, several very rare frogs and salamanders have been found, but the tiny Borneo Rainbow Toad has remained elusive. In fact, only one of the 10 species granted highest priority (the Ten Most Wanted) had turned up – Ecuador’s Spotted Stubfoot Toad, Atelopus balios. However, a 3-month-long search of the Gung Penrisser Mountains in Sarawak, western Borneo, revealed that the Rainbow Toad is still with us.

Finding a Long-Lost Amphibian

Prominent herpetologist Indraneil Das, whom I’ve had the pleasure of meeting at several conferences, led the search, which was held after nightfall among trees along high mountain ridges. Despite being brilliantly clad in red, yellow, purple, black and green, the aptly named Rainbow Toad is a mere 2 inches in length, nocturnal, and lives above ground – not an easy creature to find. But Dr. Das’ team prevailed, and 3 individuals were finally located in their arboreal hideaways.

An Uncertain Future

The Borneo Rainbow Toad is known from only two locations and likely has a tiny total range. Unfortunately, most of its habitat has been converted to golf courses and farmland, and the only streams in which its tadpoles were once found are subject to runoff and heavy siltation. Prospects for the creature’s future are dim, but conservation measures are being discussed.

Most missing and newly-discovered frogs are tiny, drab creatures that, unfortunately, excite only diehard amphibian enthusiasts. The Borneo Rainbow Toad is, however, a beautiful little beast. For this reason, the exact site of its rediscovery is being held in confidence, lest collectors move in.

Other Unusual “New” Frogs

Some surprisingly large and interesting amphibians have been found in recent years, including Thailand’s Bird Eating Frog and the world’s only known Lung-less Frog, a native of Borneo.

Please also post your questions and comments here…I’ll be sure to respond quickly.

Thanks, until next time,

Frank Indiviglio

Frog Reproduction Made Simple – Breeding Fire-Bellied Toads

Frank Indiviglio — Fri, 22 Jul 2011 13:52:45 +0000

Hello, Frank Indiviglio here. Although no frog can be classified as “easy” to breed in captivity, the Chinese or Oriental Fire-Bellied Toad, Bombina orientalis, is at least “reliable”. Two related species that appear in the trade, the European Fire-Bellied Toad, B. bombina and the Yellow-Bellied Toad, B. variegata, are also regularly bred by hobbyists.

The Oriental Fire-Bellied Toad is the most colorful and readily available of the 6 described species. Ranging from eastern Siberia to northeastern China and Korea, it makes a wonderful introduction to the fascinating world of amphibian reproduction. They are also among the most interesting anurans that one can keep – owners invariably describe them as “amusing”, and I must agree!

Step One: a Proper Diet

Frogs that are to be bred should be pre-conditioned by being fed a highly varied diet comprised of earthworms, nutrient-loaded crickets, waxworms, small guppies, beetles, moths, flies, sowbugs and other wild-caught invertebrates; please see the article below for details and suggested food animals.

Pre-Conditioning the Frogs

Unlike many frogs, this hardy creature requires very in the way of stimulation in order to come into breeding readiness. I’ve found that, when kept at typical room temperatures, normal fluctuations brought on by the changing seasons may be enough.

In order to assure success, you can lower the depth of the water in their aquarium for a few days during the springtime, and then re-fill it with water that is 5-10 degrees warmer than that in their aquarium. Alternatively, keeping the frogs at 60 F for a month or so almost guarantees that they will be ready to breed once temperatures rise.

Courtship and Amplexus

It is best to move your frogs to a separate aquarium for breeding, so that the eggs can be left in place and the adults returned to their original home after spawning has occurred. A ratio of 2-3 females for each male is desirable, but not essential.

Males in breeding condition sport dark, roughened patches, known as “nuptial pads” on their inner arms. Courting males will let forth with a short series of unique calls, and in their “lust” will grab onto just about anything within reach – including fish, plastic plants and one’s fingers!

In contrast to most frogs (but in common with African Clawed Frogs and their relatives), male Fire-Bellied Toads grasp females just above the rear legs, rather than under the front legs (please see photo); this mating embrace is known as “inguinal amplexus”. Unreceptive females will straighten out their legs and vibrate the body.

The Eggs

The breeding tank should be large, and furnished with abundant (preferably live) plants and a filter that does not create strong currents (corner filters are ideal).

Females lay 100-200 eggs, usually within 24 hours of entering amplexus; the eggs attach to plants, sticks and airline tubing. At 72 F, the tiny (7 mm) tadpoles hatch in 3-4 days. They remain motionless and attached to plants for 2 days, during which time they absorb the yolk sacs.

Rearing the Tadpoles

Once the tadpoles begin to move about, they should be fed tropical fish flakes and chopped blackworms several times daily.

Hind legs first appear around day 10, followed by the front legs on day 19-22. At this point it is important to be sure that the tank is well stocked with plants, so that the froglets can easily reach the surface. The tadpoles will exit the water onto floating cork bark, a platform or a gravel island.

The newly-emerged froglets, or metamorphs, will not eat for the first 3-4 days after leaving the water. Thereafter, they should be provided with large quantities of fruit flies, 10 day-old crickets, springtails and wild-caught aphids and tiny leaf-litter invertebrates. Nutrition is critical at this point – please see the article below and write in for further details. Sexual maturity is reached in approximately one year.

Breeding Related Species

Two related species are often seen in the pet trade – European Fire-Bellied Toad, Bombina bombina, which hails from eastern Europe, and the Yellow-Bellied Toad, B. variagata, of central and southern Europe. Both may be bred in a similar manner.

In order to be primed for reproduction, these toads require a longer, cooler “winter” than does their Asian relative. Keeping them in damp sphagnum moss for 4-6 weeks at 40-43 F (refrigerators work well for this) will suffice. Following the cooling-off period, raise the temperature to 60-70 F over 2-3 weeks, at which point the males should start calling.

A rain chamber, while not essential, will help to bring Fire-Bellied Toads (and many other species) into breeding condition; please see the article below for instructions on creating a simple rain chamber.

Yellow-Bellied Toads sometimes exhibit an orange or red stomach; such individuals are difficult to distinguish from European Fire-Bellied Toads. Check the fingers on the front limbs – those of the European Fire Belly have tiny webs; the Yellow-Bellied Toad’s fingers are not webbed. They will, however interbreed with one another, as well as with the Oriental Fire-Bellied Toad, and so exact identification of captives is sometimes impossible.

Please write in with your questions and comments.

Thanks, until next time,

Frank Indiviglio

Amphibian News – Rare Frogs Breed in Captivity, Lost Species Found

Frank Indiviglio — Fri, 10 Jun 2011 19:25:37 +0000

Hello, Frank Indiviglio here. Frogs and frog enthusiasts have much to celebrate these days. The endangered Lake Titicaca Frog, Telmatobius culeus, has reproduced in captivity, and 6 Haitian frogs, lost to science for decades, have been found.

Lake Titicaca’s Aquatic Giant

The huge, skin-breathing, cold-adapted Lake Titicaca Frog ranks as one of the world’s strangest amphibians. Known only from this lake, which straddles the Peru-Bolivia border at 12,500 feet above sea level, the unique creature is threatened by the food trade and pollution.

I had the good fortune to work with what was, at the time, the only Lake Titicaca Frogs in captivity. Despite nearly 2 decades of trials, I and my co-workers failed to raise the few tadpoles that were produced (please see article below). However, Peru’s Huachipa Zoo, in association with the Denver Zoo, has announced that 5 apparently healthy tadpoles are now being reared. A museum in Bolivia has been successful in breeding a close relative, the equally-rare Water Frog, Telmatobius hintoni.

Holding on in Haiti

Biologists feared that Haiti’s devastating earthquake of 2010 had pushed a number of frogs to extinction, as most were already limited in range to Haiti’s remaining forests (a mere 2% of their original size, please see photo). One species in particular, the La Selle Grass Frog has not been seen in 25 years. This frog was the subject of a recent IUCN effort to find “lost species”, the Global Frog Search.

Researchers focused on the most likely habitat, the relatively untouched cloud forests of Haiti’s southwestern mountains (please see photo). Although the elusive Grass Frog remained unseen, they did uncover 23 of Haiti’s 48 amphibian species, 15 of which are found nowhere else on earth. Included among these were a few pleasant surprises – 6 rare frogs that had not been observed for decades. Some brief notes on each will illustrate the amazing diversity of Haiti’s amphibians, a staggering 92% of which are threatened with imminent extinction:

Mozart’s Frog: although not discovered by its namesake, this frog produces a call that, when illustrated on a spectrogram, resembles musical notes.

La Hotte Glanded Frog: striking blue eyes distinguish this frog from all others.

Hispaniolan Ventriloquial Frog: this frog seems able to “throw” its odd, rising/falling call.

Macaya Breast Spot Frog: one of the world’s smallest frogs.

Macaya Burrowing Frog: unique in laying eggs below ground; there is no tadpole stage.

Hispaniolan Crowned Frog: sporting a head ringed by bumps, this arboreal frog breeds in Bromeliads.

Do Your Frogs or Toads Have Trouble Catching Insects?

Frank Indiviglio — Tue, 31 May 2011 13:26:02 +0000

Hello, Frank Indiviglio here. I’ve recently observed several frogs and toads to develop difficulties in feeding (American Bullfrogs, Gray Treefrogs, Southern Leopard and Green Frogs; several readers have written to me concerning difficulties with American Toads). It starts with what looks like “bad aim” and progresses to the point where the frogs cannot catch insects at all and must be force-fed. I’ve looked into the problem and found that a Vitamin A deficiency, leading to Short Tongue Syndrome, may be involved (please see this article by Dr. Kevin Wright of the Arizona Exotic Animal Hospital for details). I’d like to request that readers send me their own observations, so that we can learn more about this serious amphibian health problem.

Short Tongue Syndrome

The condition was first observed in captive Wyoming Toads, Bufo baxteri, an endangered species (please see photo).

According to the article mentioned above, studies of the feeding difficulties, labeled Short Tongue Syndrome, revealed that diets deficient in Vitamin A may prevent mucus glands associated with the tongue from producing enough saliva. The tongue is not, as the disorder’s name implies, shortened, but rather insects simply do not stick to the tongue when grabbed.

Other symptoms, such as swellings in the lower eyelid, have been reported in Leopard and various Poison Frogs.

Powdered supplements containing low levels of Vitamin A, or products that have expired or been improperly stored, may be implicated. Dr. Wright’s article (please see below) suggests possible treatments.

Vitamin A and Calcium: My Experience

The afflicted frogs and toads under my care were fed largely upon wild-caught insects during the warmer months, a strategy that has served me well for decades, so I suspect the problem does lie with the Vitamin A content of supplements used during the winter.

Several individuals have also exhibited poor coordination and difficulties in getting about, which sometimes points to Calcium-related disorders. I’m looking into several possibilities and will post updates.

In the meantime, it would be very useful to have your own thoughts and observations. We know very little about amphibian nutrition and medicine, and any input would be most valuable. Please post your comments here if possible.

Thank you,

Frank Indiviglio

That Reptile Blog » Toads

Best Tadpole Foods (Based on my Experiences) – Seeking Additional Suggestions

The Amazing Specialists

General Considerations

Reptomin Floating Food Sticks (Tetrafauna)

Canned and Sun-Dried Freshwater Shrimp (ZooMed)

Tropical Flakes Fish Food (TetraMin)

Spirulina Discs (Wardley)

Earthworm Fish Food Flakes (Zoo Med)

Repto Treat Delica Bloodworms (TetraFauna)

Further Reading

Amphibian Declines – Pollution Worsens Disease and Parasite Attacks

Parasites and Insecticides: a Confusing Scenario

Are Pathogens Changing?

The Role of Stress

What’s Next…What Can I Do?

Further Reading

Chorus Frogs and Chytrid Bacteria – a Look at the Confusing new Reports

Resilient Chytrid Carriers

A Protective Bacterium

Don’t Blame Chorus Frogs!

Other Chytrid Concerns: Amphibians as Food and Bait

Further Reading

Spotted Salamanders Adapt to Salt and other Roadside Toxins

“Salt Water” Salamanders

Only the Strong Survive…

Further Reading

Amphibian Medicine – Cold “Resurrects” Hellbender and Sick Frogs

Cold Tolerant Amphibians

Early Experience with Cold Treatments

Recent Experiences

Conflicting Results: Cold Hinders Recovery

Observation: Snapping Turtle in February

Further Reading

World’s Smallest Frogs Added to 2011’s List of Newly-Discovered Amphibians

Tiny Frogs and Fish

Minute Predators and Prey

Diversity Hotspots

Further Reading

Multicolored Rainbow Toad, “Missing” since 1924, is Found in Borneo

“Ten Most Wanted”

Finding a Long-Lost Amphibian

An Uncertain Future

Other Unusual “New” Frogs

Further Reading

Frog Reproduction Made Simple – Breeding Fire-Bellied Toads

Step One: a Proper Diet

Pre-Conditioning the Frogs

Courtship and Amplexus

The Eggs

Rearing the Tadpoles

Breeding Related Species

Further Reading

Amphibian News – Rare Frogs Breed in Captivity, Lost Species Found

Lake Titicaca’s Aquatic Giant

Holding on in Haiti

Further Reading

Do Your Frogs or Toads Have Trouble Catching Insects?

Short Tongue Syndrome

Vitamin A and Calcium: My Experience

Further Reading