[Illustration: Salamander]
TOADS AND FROGS
(order Anura)
Background.
The toads and frogs evolved from salamanders some 180 million years ago
(Triassic period). They have changed little since they developed the
large, jumping-type legs, and have become very successful. Today there
are over 2,600 species of toads and frogs, and they live in a variety of
environments.
With proper care, most toads and frogs do quite well in captivity.
Knowing their natural history can help to furnish the keeper with the
information necessary to keep these amphibians in good health.
Selection of Species to be Kept.
The selection of the proper anuran (toads and frogs) for you to keep
depends partially on where your interests lie. If you are interested in
toads, then the common species in your area may be selected (Missouri
common toads include the American and the Fowler's toad). The very large
Marine toad, _Bufo marinus_, is a species that is quite hardy in
captivity, and are not expensive to purchase.
Spadefoot toads (genus _Scaphiopus_) are rather difficult to collect,
except during their breeding season, and they are extremely shy and
rather difficult to keep. They do not make a very good study animal
because they tend to spend a great deal of time buried at the bottom of
their vivarium.
The treefrogs generally do well in captivity, but only the larger
species should be considered. The very small varieties should be
delicate, and require very small insects to feed on. The gray treefrog
(_Hyla versicolor_) and green treefrog (_Hyla cinerea_), both are found
in Missouri, as well as the barking treefrog and Cuban treefrog (Florida
species), are easily kept, provided they are given a variety of live
insects to eat.
The majority of true frogs (genus _Rana_) can be kept with little
trouble, but--as with all animals--they should be kept as clean as
possible. The leopard frog (_Rana pipiens_, _blaira_, and _utricularia_)
will do well, so also will the green and bull frog (_Rana clamitans_ and
_R. catesbeiana_).
Because they are bred in captivity, the clawed frog, _Xenopus_, of
Africa is available in many pet stores at reasonable prices. These
completely aquatic frogs can do quite well in captivity. Another
tropical frog species that is often sold in pet stores is the South
American horned frog, _Ceratophrys_, which will eat both crickets and
baby mice.
Choosing other species not listed in this section will have to be done
at the discretion of the person keeping them. You may choose a species
that is either too fragile (as with very small toads or treefrogs), or,
if exotic species are what you are interested in, their price may be the
deciding factor (some Central American frogs can be expensive).
No matter what type of toad or frog you intend to keep, remember that
they require live food, and should never be kept in crowded conditions.
Thus, keep in mind that insects are difficult to secure in the winter,
and, the more specimens you have, the greater the problem will be to
feed them. It is recommended that only one or two toads or frogs be kept
at one time--get to know the animals, learn from them, and then move on
to other species. Release native species in a suitable area--but never
release non-native species into a new area ... give them to a zoo or
biology teacher.
One last reminder: always wash your hands after having handled your
captives. The skin secretions can be very irritating to the eyes.
Housing Your Captive Toad or Frog.
As with salamanders, the toads and frogs can be put into two categories:
1. Aquatic, and 2. Terrestrial (living on land). Both types of
amphibians can be successfully kept in aquaria.
[Illustration: American Toad
_Bufo a. americanus._]
1. Aquatic and semi-aquatic toads and frogs. The truly aquatic toads and
frogs that are often kept in captivity by amateur herpetologists are the
South American Surinam toad, _Pipa pipa_, and the African clawed frog,
_Xenopus laevis_. Both forms can be kept in a 10-gallon aquarium with
gravel on the bottom, a few rocks, and some aquatic plants. A secure top
should always cover the top of the aquarium. The water should be
filtered, and a temperature of 70 to 78°F will do nicely for these
species. The water level of the aquarium can be from 6 to 10 inches.
Many of the true frogs (genus _Rana_) can be kept in a semi-aquatic
condition. That is, a few inches of water on one end of the aquarium,
and some type of land area on the other end. In this way, the frog can
either be in the water or out--whatever it wishes. One way to set up
this situation would be to use a 10-gallon aquarium with a little gravel
on the bottom, and a few large, flat rocks for the frogs to climb onto
can be put in. A screen top must be put on the top to keep the frogs
inside. If bullfrogs (_Rana catesbeiana_) are to be kept, a 15 or
20-gallon aquarium would be needed. With this set-up, the water should
be changed at least twice per week. To give the amphibians a sense of
security, the back and sides of the aquarium should be painted a dark
brown or black (paint the outside glass). Try to avoid any bright lights
over your toads' or frogs' aquarium.
2. Terrestrial and Arboreal Species. All of our native toads are adapted
to life on land. In captivity they will do well if given a few inches of
soil (1/3 black dirt, 1/3 peat moss, and 1/3 fine sand), a few pieces of
bark to hide under, and a small, shallow water dish. A 5 or 10-gallon
aquarium will do. The sides and back should be painted a dark brown or
black, and a screen top will be needed to keep them inside. The soil
mixture should be replaced every few weeks for proper sanitation. If the
soil mixture becomes too wet, it should be replaced.
Besides most toads, the South American horned frog, _Ceratophrys_, the
African burrowing frog, _Pyxicephalus_, and the spadefoot toads,
_Scaphippus_, can be kept in this type vivarium. However, if you notice
that the bottom of the toads' or frogs' hind feet are becoming raw from
too much digging, it may be best to keep them on wet paper towels rather
than on any soil.
_Treefrogs._
A typical terrarium set-up will work very well for most treefrogs. But,
even though you may have the most beautiful terrarium plants--the
treefrogs will spend most of their time sticking to the upper corners of
the aquarium. Besides plants, a few small branches and a shallow water
dish are also required. Spraying the terrarium once-a-day will do the
treefrogs and the plants some good.
The temperature for most treefrogs or terrestrial toads and frogs can
range from 68 to 75°F. However, tropical species should not fall below
70°F.
[Illustration: Green Frog
_Rana clamitans_]
Food and Feeding.
Becoming familiar with the natural history of your captive amphibian
will help you determine what they can be fed. Giving your toad or frog a
variety of live insects is a good practice. For the totally aquatic
species; earthworms, minnows, goldfish, shrimp, and even small tadpoles,
are all eaten by them. If these are not available, try small pieces of
raw fish, liver, or beef. Toads and large frogs will eat mice--the size
depending on the size of the toad or frog.
Feeding your animals by just dumping in a number of crickets, worms, or
flies is a very poor management practice. For one thing, if you have
several toads or frogs in one aquarium, the stronger, more alert animal
will probably eat more than the others, and one or two will be under
fed. Also, if you add live crickets to a well planted terrarium, many of
the plants will be eaten by the crickets before they are eaten up
themselves. It is thus strongly recommended that all your toads and
frogs be fed by hand, using a thin wire or long pair of forceps. Place
the cricket or worm on the end of the wire and move it in front of the
amphibian. In this way you can be sure all are getting the proper amount
of food, and this is also a good way to feed such things as liver or
pieces of raw beef.
As a general rule, all your toads and frogs will do well if fed on a
regular basis of 2 to 3 times per week. It is good practice to dust the
worms or insects once a week with a calcium/phosphorus powder. This will
supply your specimens with the much needed minerals.
Tadpoles.
It happens so often that people have seen tadpoles (Toad and frog
larvae) in ponds or puddles while out in the country, and have taken
them home--only to find out they have no idea how to care for them. The
development of these amphibians can be a real learning experience for
children, and with proper care, your tadpoles can mature to small toads
or frogs.
Overcrowding and lack of proper food are two mistakes made most often by
people who try to keep tadpoles. One half to one dozen is more than
enough to try to keep. Put them in a shallow pan, with 1 to 3 inches of
water in it. The larger the tadpoles, the deeper the water should be.
Insert an air stone to keep the water in motion. No rocks or gravel are
needed, but some live aquatic plants can be put in with them. KEEP THEM
CLEAN. Never allow the water to stand dirty for more than a few hours.
Be sure that the clean water is free from chlorine.
To feed your tadpoles, it is essential to give them a variety, and to
furnish them with both plant and animal foods. Their staple diet could
be boiled lettuce, rabbit chow, and cooked liver. Give them small
amounts of food at one time. You can feed them 3 or 4 times a day. When
you see the water is becoming dirty--change it. You may want to try and
feed them a tropical fish food called "molly flake food"; or you might
try some hard boiled egg. Keep the water temperature at 70 to 72°F.
Once the tadpoles begin to lose their tails, grow front legs, and take
in air at the surface, they are beginning to turn into a toad or frog.
At this stage, they should not be disturbed. When they no longer have
any tail, and stay out of the water, they can be fed a variety of small
insects, or small pieces of earthworms.