Amazon Milk Frog
Species
Amazon milk frog (Trachycephalus resinifictrix)
Size
Adults milk frogs 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. Male Amazon milk frogs 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
Provide a large bowl of clean water for Amazon milk frogs to soak in. The water should be changed daily. 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 offered. Place the UVB light bulb over screen rather than glass 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.
Hi, Devin:
I have been reading your articles with great interest over the last few days. I have a question for you, if you don’t mind, relating to possibly bringing a pair of Amazon milk frogs into my family.
I have a paludarium that is 36″ w x 36″ h x 18″ d, and I have not yet set it up. I had a White’s tree frog (that I adopted) for about 12 years, and had bought the paludarium for her, but then became hesitant to move her from her existing 30 gal aquarium setup, as she seemed to be getting older, and I didn’t want to upset her routine. She recently passed on, and we miss her terribly, but also feel that we don’t want to “replace” her with another White’s, and would prefer to just set up the paludarium and get it bioactive and stable before seriously considering a pair of new frogs.
That said, I feel it would be best to at least have an idea of which species we might get, so that we can design the space with that species in mind. I have been reading your articles, as well as others, and feel that Amazon milk frogs would be a good choice for the kind of space we have in mind, as well as for transitioning to a new species. I have a rather large collection of tropical plants, and would want to create a tropical environment in the paludarium, with various water features, including a fogger, a trickling waterfall, and a body of water at the bottom, with tapering sides, so that frogs can get in and out easily.
My question, or I guess, two questions, are if you think this sounds like the right sort of setup for these frogs (or what would you suggest), and also, specifically, if you think I can get away with having a rather deep water feature at the bottom (the paludarium can hold 20 gallons, but I was thinking more like 15), provided that I put in enough plants and structure (in corners, and then some) for the frogs? I have a filter and tubing for the water feature, which I got because I wanted to do the waterfall thing, but I believe the water has to be deep enough to accommodate it, plus I have an interest now in water plants. I’m also kind of fish-curious, and am wondering if Amazon milk frogs, with their habit of staying up high, might be a suitable choice for including a few tropical freshwater fish…
Thank you, and I apologize for this being so long. I really want to take my time and get this right.
–Leha
Leha, I think Amazon Milk Frogs are a great choice for your next frog. Their care is very similar to White’s Tree Frogs, which you have experience with already. In the wild, they live high up in the canopy and breeding tree holes. Recently, another closely related Trachycephalus has become available and bred in captivity, Trachycephalus coriaceus (for example: https://www.joshsfrogs.com/chocolate-milk-frog-trachycephalus-coriaceus-captive-bred.html), so that might be another species to look into.
As for the setup, usually for tree frogs, it is easier to have a terrestrial setup with a water dish you just change every day. Tree frogs can be pretty dirty. However, it sounds like you have a large tank and the water area will be 15+ gallons and filtered, so in that case, you can maintain water quality more like an aquarium with regular partial water changes and a healthy load of beneficial bacteria keeping up with any waste the frogs produce. It also sounds like you have already considered that the tree frogs need plenty of surfaces to live on above the water, and you might be able to accomplish this with pieces of cork or other wood that is positioned more horizontally so they are not just stuck sitting vertically all the time above the water (not ideal). At a minimum, leave a section at the bottom of the tank as land, if for no other reason than to allow crickets or other food items to climb out of the water if they fall in. Also, make sure there are dry areas up high. If you have a water feature and water below and no real dry areas for the tree frogs, you might be better off going with a semi-aquatic frog species rather than a tree frog. I guess another consideration is drowning. I don’t think it is a large risk for milk frogs, but it would reduce the risk of drowning to have some large angled pieces of wood or rocks that protrude from the water’s surface. Lastly, for fish, you can give it a shot. Don’t stock too heavily, and stick with small hardy fish, probably that are coldwater tolerant.
Good luck,
Thank you so much, Devin–this is super helpful.
I have plantable “shelves” that I got with the paludarium, which sit a few inches above where the water level would be, so the frogs would have these, with various items to perch on, in the upper regions of the space, as well as the central, more vertical column of bark and background that would slope up and down the length of the paludarium, with the drippy waterfall feature winding down that. I am also working out how to create a “tree hole” or two for them. I have built planters for some of my plants out of cork rounds with a saucer or plastic pot slipped in from the broad end to support the plant. I’m thinking if I could get the right rounds and do something similar, maybe using terra cotta, then also saw out a circle on the side, just above where the saucer is placed, that might work. I would love to recreate as closely as possible the sort of home they would expect to live happily in, if living wild.
Thank you also for the fish recommendation. One of the things I wanted to do before introducing any animals was to scope out the temperatures and humidity of the various microclimates in the space, and then adjust those to the needs of the species. I can see it makes sense that the water, being at the bottom, might not get as warm as a warm-loving fish would want. Although I do keep my house pretty warm (71-72 F) because, tropical plants. 🙂
Anyway, I’m rambling on a bit. Thanks again. I so appreciate your making yourself a resource to enthusiasts. It’s hard to find solid info on the Internet, in the sea of opinions.
Kind regards,
Leha