Amazon Milk Frog

Overview

The Amazon milk frog is a large tree frog from the rainforest canopy of northern South America ¹². Its skin is bumpy, gray, and banded with brown and black. Its feet have large toe pads, and juveniles are more boldly marked than adults ¹. The Sacramento Zoo gives an adult length of 2.5 to 4 inches, an estimated wild lifespan of 15-plus years, and up to 25 years in human care ¹. Females grow larger than males: up to 3½ inches compared with 3 inches, according to the San Francisco Zoo ².

The name comes from the sticky, milky white secretion it releases when threatened. The secretion is poisonous to predators ¹³.

A note on our sources. No veterinary care sheet covers this species. The husbandry targets below come from veterinary guidance for tropical amphibians in general ⁴⁵, plus natural history from zoos ¹²³.

Natural history

Milk frogs range across northern South America, including the Guianas, Suriname, Venezuela, Colombia, Ecuador, Peru, Bolivia and Brazil ¹². They are arboreal, living high in the canopy and climbing with toe pads that can hold many times their body weight ¹³. They hide under leaves by day and are active at night ¹². They call loudly at dusk and dawn, using their large vocal sacs ¹².

Wild milk frogs eat insects, spiders and other small invertebrates, and sometimes other amphibians ¹². The IUCN lists the species as Least Concern ¹².

Enclosure

• Tall and planted. Milk frogs live in trees ¹³, so give them height. Provide sturdy branches, perches and hiding places among leaves ¹⁴.
• Live plants. Live plants purify air, raise humidity and give hiding and perching spots ⁴.
• Secure, ventilated lid. Aim for about 1 to 2 air changes per hour ⁴⁵.
• Water. Even tree frogs need a shallow water dish ⁴.
• Clean water only. Water must be free of chlorine, chloramine, ammonia and other toxins. Never use distilled water ⁴.

Temperature & lighting

Merck notes that tropical amphibians may need 75 to 80°F, and that frogs kept outside their preferred range can become immunosuppressed and develop secondary infections ⁴. Keep at least one thermometer in the enclosure ⁴.

Merck's owner guide says UVB lighting is required to prevent metabolic bone disease in amphibians. Replace bulbs every 6 to 8 months or as the manufacturer directs ⁴. Milk frogs are nocturnal and spend the day hidden under leaves ¹², so give them shaded cover under the light. Live plants help by filtering light ⁴.

Humidity

Merck's general guidance is 75–80% humidity for most amphibians and 85–90% for tropical species ⁴. Use a humidity gauge and maintain humidity by misting, or with a humidifier or waterfall ⁴. Good ventilation must go hand in hand with high humidity ⁵.

Substrate

Soil free of additives, sphagnum moss, untreated hardwood mulch and leaf litter are all options. Avoid cedar and pine, which contain toxic oils ⁴. Spot-clean daily to weekly, and replace the substrate every few weeks to months, leaving a portion of established soil or moss behind each time ⁴.

Diet & supplementation

• Prey. In zoos, milk frogs eat crickets, worms and flies ¹.
• Supplements. Insect-only diets without enough calcium, the right calcium–phosphorus balance and vitamin D3 cause metabolic bone disease. Ask your vet to set a supplement schedule ⁷.
• Daily care. Replace food and water daily, and remove leftovers ⁴.

Handling & temperament

Most frogs should be left in their enclosure, because their skin is easily damaged by handling ⁶. When you clean, scoop the frog into a container rather than grabbing it ⁶. Milk frogs release a milky toxin when stressed ¹, so wash your hands after any contact. Amphibians can also carry Salmonella ⁹.

Health

Common issues

• Metabolic bone disease from poor diet, supplementation or UVB ⁴⁷.
• Bacterial diseases, such as red-leg syndrome, often triggered by changes in temperature, diet, crowding or cleanliness ⁸.
• Secondary infections when kept too cold or too hot ⁴.

When to see a vet

See an amphibian vet for weakness, loss of balance, skin color changes, red spots, swelling or redness of the legs ⁸. An amphibian vet can also advise on exact temperature and humidity targets ⁴.

Breeding overview

In the wild, milk frogs breed in the rainy season ¹². Males call from water-filled tree hollows or bromeliads ¹². The female lays her eggs in the hollow, and parental care ends there ¹. Tadpoles develop in the tree hollow, and the male may keep calling in other females whose eggs become food for the earlier tadpoles ¹. The Sacramento Zoo gives sexual maturity at about one year ¹.

Legal & ethics

The IUCN lists the Amazon milk frog as Least Concern, but logging and agriculture threaten it in parts of its range ¹. Like all amphibians, it is vulnerable to pollution and to chytridiomycosis, a fungal disease that has devastated wild frogs worldwide ¹. Never release pet frogs, and dispose of used substrate and water carefully to avoid spreading pathogens ⁵.

Sources

1. Amazon Milk Frog · Sacramento Zoo
2. Amazon Milk Frog · San Francisco Zoo
3. Fun Facts About Amazon Milk Frogs · Smithsonian's National Zoo and Conservation Biology Institute
4. Housing for Amphibians · Merck Veterinary Manual
5. Environment and Husbandry for Amphibians · Merck Veterinary Manual
6. Frogs as Pets · VCA Animal Hospitals
7. Nutritional Diseases of Amphibians · Merck Veterinary Manual
8. Common Infectious Diseases of Amphibians · Merck Veterinary Manual
9. Salmonella, Feeder Rodents, and Pet Reptiles and Amphibians · U.S. Food and Drug Administration

Last reviewed 2026-10-24 by Novel Fauna. This guide is general husbandry information, not veterinary advice. When an animal is sick, see a veterinarian experienced with exotic animals.

Revision history

1. 2026-10-24 Library complete: 20 more cited guides (70 total), Invertebrates group, care targets migration 0020, source title fixes 5cf06a2

Evidence grades: Novel Fauna editorial: source classification, not yet expert-reviewed, 2026-10-25. What the grades mean.

Report an issue