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STEVE GRENARD is an avid herpetologist with more than 40 years of experience with amphibians and reptiles. He is also the author of Bearded Dragon, Your Happy Healthy Pet, Second Edition.

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The authoritative information and advice you need, illustrated throughout with full-color photographs--now revised and redesigned to be even more reader-friendly!

Frogs and toads are perennial favorite pets. They include easy-to-care for breeds and intriguing, exotic varieties. For both first-time pet owners and life-long hobbyists, frogs and toads can make fascinating pets, but it is essential to learn how to care for them properly. With colorful photos, charts, and tables, this guide covers the basics, including:

Choosing your frog or toad

Creating and maintaining your pet's new habitat

Feeding and caring for your frog or toad

Keeping your pet healthy

You'll also learn about the varieties of frogs and toads, and about their existence in the wild.

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Frogs and Toads

John Wiley & Sons

Chapter One

Frogs and toads are four-legged, tailless, air-breathing vertebrates that represent the link between the fish and reptiles and all other air-breathing species, including humans. They are members of a class or group of vertebrates known as the Amphibia, a word that means "dual life" and refers to the fact that amphibian life occurs in two phases-one in the water and the other on land. It also alludes to the fact that many amphibians are, well, amphibious, and are as fully at home in the water as they are on land (although there are many notable exceptions, including species that never leave the water and others that stay on land or in trees and never enter the water at all).

The first amphibians, the labryinthodonts, took the great leap from water to land during the Devonian period some 400 million years ago. However, fossils of frogs appear much later, in the Jurassic period of North America, some 280 million years ago.

The other amphibian groups or orders include the Caudates or Urodeles, which are known familiarly as salamanders and newts, and an obscure order known as the Apoda (legless amphibians), or caecilians. These segmented, wormlike creatures are found primarily in tropical regions and remain burrowed in moist soil most of the time. Little is known of their habits or life history.

Clearly, of all the amphibians, frogs and toads are the most familiar and best studied. Frogs and toads are members of the order Anura, a term that means "tailless," which is exactly what they are-bereft of a true tail, unlike their salamander cousins.

So Many Frogs and Toads

There are more than an estimated 5,200 species and subspecies of frogs and toads in the world, but nobody knows exactly how many there really are because new species and subspecies are being discovered by scientists at the rate of more than a dozen a year. Amazingly, it is predicted that such discoveries may go on indefinitely, as long as the precious habitats of these animals is protected from destruction. Environmental insults and habitat destruction have already caused the extinction of countless species over the last few decades; it is theorized that some rare species became extinct before scientists learned of their existence. Since 1980, at least 120 species of amphibians are believed to have become extinct, although there may be many more.

The number of different species of frogs and toads increases as the climate gets warmer, and the neotropical and tropical regions of the world tend to have more species than the temperate, and therefore colder, climates. In one small valley (San Cecilia) in Ecuador's Amazon basin, scientists discovered a total of eighty-one species of frogs and toads, finding fifty-six in just one night! This is all the more remarkable when you consider that there are about ninety frog and toad species in the whole United States.

Frogs and toads are an essential part of our ecosystem. Each individual animal consumes untold quantities of insect pests in a single day and helps to keep noxious insect populations in check. Without frogs and toads, the Earth would be overrun with crop-eating and disease-spreading bugs.

Their existence also provides food for larger carnivores, including humans. Their larvae, or tadpoles, consume aquatic weeds that might otherwise clog up waterways. Clearly, frogs and toads play a vital role in the environment, and there is no telling what would happen if they suddenly all disappeared.

But disappearing they are. It is feared that frogs are declining in overall numbers, and some populations have completely vanished for reasons we do not yet understand. Even casual observers walking in wetlands they've visited for years are now finding that the frogs or toads that were once there are no longer present. More alarming still is that this loss of wildlife is occurring even in seemingly pristine and untouched habitats. These declines baffle environmentalists, who hope that by studying frogs in captivity as well as in the wild they may one day solve these mysterious absences.

Classifying Frogs and Toads

The most basic units of any animal or plant classification system are the species and subspecies. And although there have been many efforts to precisely define what a species is, it is impossible to establish any firm rules that apply in every case. Members of a single species all look alike, live in a similar habitat, eat the same foods, and reproduce in the same manner, usually with one another. The exception is when two different species accidentally mate and produce a hybrid. Over time, if these hybrids survive and breed with one another, a new species is eventually created.

Some animals are similar enough to be considered members of the same species, but there may be slight differences in different populations. This results in a subspecies category.

Above the species level, all animals that are very similar in general appearance are members of a genus, and above that they belong to a larger group called a family. These classifications are generally based on anatomical similarities.

Naming Species and Subspecies

Every species has a two-part Latin or Greek name and subspecies have a three-part name. The first part of the name is its genus, and the second part is its species. If there is a third part, it's the subspecies designation. Thus, the American bullfrog, with no known subspecies, is a member of the genus Rana and species catesbeiana. Its scientific name is written: Rana catesbeiana.

In the printed literature, scientific names are always italicized. The full classification of the American bullfrog is written as follows:

Phylum Chordata (animals with a spinal cord)

Subphylum Vertebrata (animals with a backbone or vertebral column)

Class Amphibia (amphibians)

Family Ranidae (the family of true frogs and riparian frogs) Genus Rana (the true frogs)

Species catesbeiana

There are about forty-one families of frogs and toads, but only some of the best known, most interesting, and more commonly studied groups will be included in this book-although others will be briefly mentioned in chapter 7, which lists many species that may be kept as pets.

What's the Difference Between a Frog and a Toad?

The difference between a frog and a toad is actually more illusory than real. Both terms have been used interchangeably in different parts of the world. There are some generalizations that can be made about the way the terminology is used in the United States though.

First and foremost, all toads are frogs, but all frogs are not necessarily toads-although a few are. So regardless of whether you call a particular species a toad, it is still technically a frog.

In the United States, we tend to classify toads as mainly terrestrial or land-dwelling amphibians that enter the water only to breed and lay their eggs. We tend to think of frogs as aquatic or semiaquatic animals-equally at home in the water and on damp ground.

The problem with this definition is that there are frogs that never or rarely enter the water except to breed, such as the tree frogs-frogs that, as a rule, spend as much time as possible up in the...