Common Names: Amazon milk frog, milk frog
Size: Adults grow to between 2.5 and 4.0 inches (6.3 to 10.0 cm). Males are smaller than females.
Appearance: A hefty and robust tree frog, Amazon milk frogs change colors as they age. Young frogs are banded in black and white but as they mature their contrasting colors being to blend together. The black lightens to a dark gray or brown, while the white changes to gray. This takes about one year.
Distribution, Habitat and Behavior: Milk frogs have a large distribution in South America where they live in the rain forests of the Amazon Basin. Here they are arboreal and can be found living more than 100 feet above ground. Life in the canopy has resulted in an interesting reproductive strategy involving tree holes. Males vocalize from hollow water-filled tree holes to attract mates and defend territory. Breeding takes place in the holes, where tadpoles develop and once metamorphosis is complete the young milk frogs leave the water having never touched ground. The common name “milk frog” refers to the poisonous white skin secretions the frog can secrete when threatened, though they won’t do this in captivity unless heavily disturbed and mishandled.
Availability: Amazon milk frogs have become increasingly common in the pet trade. Almost all frogs available are captive-bred and it is usually not difficult to locate healthy individuals directly from breeders or listed in online classifieds. They are also occasional found for sale at pet stores.
Housing: Amazon milk frogs are large tree frogs that should be kept in an enclosure that offers plenty of room. A standard 29 gallon aquarium that measures 30 inches long by 12 inches wide by 18 inches high (76 cm by 30 cm by 46 cm) is enough space for two to four adult frogs, although more room is better. A tight-fitting screen cover is essential to prevent escapes. Attaching a background to all but one side of the aquarium reduces stress and helps frogs feel secure.
In the enclosure should be a substrate, perches, and hiding/resting areas. There are many substrates that can be used. Coconut husk fiber or other safe soil is a good option. Avoid soils that contain vermiculite or perlite. Simple substrates such as moist paper towels or foam rubber can also work. Some keepers also have success keeping Amazon milk frogs in enclosures with no substrate, but in this case it is important to flush the enclosure with water regularly to remove waste. Gravel and small bark chippings are best avoided since they can be accidentally ingested by frogs.
Perches can consist of sturdy pieces of drift wood, cork bark tubes, bamboo poles or pieces PVC piping. The Amazon milk frog is arboreal and will do best when provided with hiding spots that are at the top of the cage rather than on the floor. These can be created by resting curved pieces of bark against the side of the cage or by attaching other types of hide spots to the side of the cage with silicone sealant. Some keepers choose to create a hole in a tree on one side of the cage for use as a hiding area, for example by wedging a large cork bark tube into a water dish.
Water: A large bowl of clean water should be provided at all times. The water should be changed daily or when it appears dirty. If tap water is used it should be treated with a tap water conditioner that removes chlorine, chloramines and heavy metals.
Temperature and Humidity: The temperature can range from 75°F to 85°F (24°C to 29°C) during the day with a drop at night. Milk frogs are tolerant of a wide range of temperatures and do fine when temporarily kept outside of this range. A low wattage incandescent light bulb can be used to heat the cage. Use infrared bulbs for heating at night if needed. The Amazon milk frog is native to rainforests of South America and the humidity level that they are kept at in captivity should mimic that of their natural environment. To achieve high levels of humidity, their enclosure can be sprayed with water once or twice a day.
Lighting: In addition to providing heat, light that produces low levels of UVB radiation should also be provided. This UVB light bulb should be placed over the screen and in an area where the frog will be exposed to this beneficial light on a regular basis (for example, above a favorite perch or sleeping area). UVB helps milk frogs metabolize calcium in their diet and is needed to help avoid metabolic bone disease. The amount of UVB radiation bulbs produce slowly dissipates with use so make sure to replace the light every six months or so.
Food: A large frog with a large appetite, milk frogs accept the normal selection of feeder insects including crickets, wax worms, roaches and worms. Some adult frogs will also accept pre-killed pinky mice. The majority of their diet should consist of crickets that are the length of the width of the frog’s head or so in size. A feeding schedule of three to eight crickets every two days per frog should work well for adults, while juveniles should be fed daily. Other food items can be offered once every week or two instead of crickets. Coat crickets in a high quality powder nutritional supplement before feeding to frogs to help avoid long-term health issues related to vitamin and mineral deficiencies.