Amphibians are solidly represented as captives in both private and institutional collections. Many amphibian species are
in precarious situations in their natural habitats due to environmental changes and disease. As a result, many captive populations
are extremely valuable from a conservation standpoint. For all of these reasons there is currently a strong need for capable
amphibian veterinarians in both institutional and private practice. An important point to understand regarding amphibians
is that although they are lumped with reptiles as "herptiles", in reality they are quite dissimilar. Amphibians are indeed
vertebrates and ectothermic, however the similarities end there. Generally speaking, amphibians are less tolerant of husbandry
problems than reptiles. Amphibians do not tolerate temperature fluctuations readily and are exquisitly sensitive to water
balance problems and environmental toxins due to the permeable nature of their skin.
An in depth description of configuring vivaria for amphibians is beyond the scope of this abstract. The interested clinician
is encouraged to read more complete references such as Amphibian Medicine and Husbandry by Wright and Whitaker (2001).
Captive amphibians typically do best when housed in complex, naturalistic vivaria that reflect the natural history of the
species. Natural behaviors (including reproduction) are encouraged when the amphibian is able to interact with the environment
appropriately. In addition, a properly constructed and stocked naturalistic vivarium will establish a biological cycle and
require infrequent servicing. Alternatively, some species tolerate rather Spartan captive environments. These types of environments
offer the advantages of being easier to keep clean and allow for more intense monitoring of individual animals. Hospital
and quarantine vivaria are often minimalistic to allow easy care of the amphibian patient.
Large frogs and toads can be difficult to house appropriately due to their inclination to try and jump through clear barriers,
which often leads to traumatic injury and infection. Enclosures need to be of appropriate size for these animals and ideally
visual barriers should be employed to discourage them from jumping into the walls. Great care should be taken to avoid having
sharp or abrasive surfaces in the amphibian vivarium. Amphibian skin is extremely delicate and can easily be damaged, potentially
resulting in severe injury or introduction of infectious organisms.
Ventilation is important and an appropriate level is often difficult to maintain without sacrificing adequate levels of humidity
(most species require around 70% humidity, though a humidity gradient is recommended). The keeper needs to tinker a bit with
vivarium configuration in an effort to balance ventilation and humidity. With large collections housed in a designated room,
humidifiers can be used effectively. Otherwise, manipulation of the amount of airflow in a vivarium can be accomplished by
covering (or uncovering) ventilation ports, adding fans, etc. Also, addition of water features or misting systems can achieve
humidity goals without sacrificing ventilation.
Basic substrate for most terrestrial amphibian vivaria can consist of a layer of pea gravel which may or may not be covered
by sheet or sphagnum moss, leaf litter, mulch or soil. If simple gravel is chosen it should either be too large for the animal
to ingest or small and smooth enough that it can be passed without complication. Soil is generally avoided, unless necessary
to facilitate burrowing, as it typically goes foul more quickly than the other described substrates. It is best to avoid
using peat moss or other acidic materials as the resultant pH of the substrate may be inappropriate for most species. Soft
wood mulches (such as cedar) and those containing sharp or abrasive particles should be avoided for safety reasons. Substrates
purchased from garden and home improvement stores should be free of pesticides, fertilizers and soil aerating materials such
as perlite. Substrates can be collected from outdoor areas thought to be free of chemical contamination and can be treated
via freezing for 2-3 weeks or heating in an oven to 200 F for 1-2 hours. A moisture gradient should be present within the
substrate of the vivaria, which allows the amphibian to choose the appropriate conditions for its proximate needs. In general,
substrate should be moist without being foul. Most natural substrates will need to be changed every 3-6 months to avoid bacterial
In simple vivaria, the substrate can effectively consist of moistened, unbleached paper towels. The paper towels will need
to be changed frequently as they quickly become unhygienic. For completely aquatic amphibians gravel or fine sand can be
used as substrate or the floor of the tank can be left bare. If the floor is left bare, efforts should be made to make it
appear opaque to the amphibian to discourage continual attempts to swim through it. This can be simply accomplished by placing
colored paper underneath the tank.
Three basic rules should be followed when selecting furnishings for amphibian vivaria. First, the item should be free of
any sharp edges or abrasive surfaces that may damage delicate amphibian skin. Second, the item should be non-toxic and easily
cleaned. Third, the vivarium furnishings need to be stable so they don't fall and crush the animal. Rocks and hardwood branches
can be used successfully following disinfection. Plastic items can also be used as long as they are capable of being cleaned
Rules for plants follow the same basic outline as for vivaria furniture. The vast majority of adult amphibians are strictly
carnivorous, so there is very little potential for ingestion of a toxic plant. Secondary intoxication is theoretically possible
if an invertebrate prey item ingests a toxic plant and is then eaten by the amphibian. This small possibility can be further
minimized by not feeding more than can be eaten in a short period of time or providing alternative food for the insects.
Plants should be selected that do not have sharp spines or other features that may injure the amphibian, otherwise selection
is limited to what will survive in the vivarium. It is usually easiest to place plants in plastic pots prior to situating
them in the vivarium. By leaving the plants in pots, one will not need to maintain a soil substrate in the vivarium. This
approach also allows plants to be changed out without disrupting the entire vivarium.
It is paramount that captive amphibians be provided with comfortable hide areas within the vivarium. Selection and configuration
of hide areas will reflect the natural history of the species (i.e. arboreal frogs will not use a cave on the substrate).
Multiple hide areas within the temperature, humidity and light gradient should be provided. Most animals will choose perceived
security over other appropriate environmental parameters. Amphibians without satisfactory hide areas often do poorly. Along
this same line, amphibian vivaria should not be placed in high traffic areas in order to avoid stress due to excess noise,
vibration and light. Many times a beautifully constructed, appropriate vivarium is rendered inhospitable by being placed
in the family room where constant activity and erratic light cycles cause disruption of normal behavior and stress.
Amphibian enclosures need to be escape-proof. Many captive amphibians have succumbed to desiccation following escape from
their vivarium. Tight fitting lids are a must. If a large collection is housed in a single purpose room it may be advisable
to place small humidity retreats on the floor so that potential escapees may seek refuge and avoid desiccation.