Black milks are a Central American milk snake found mainly in the high-altitude cloud forests of Panama and Costa Rica. Black milks start off as big, tricolored hatchlings (red base color with some black tipping on scales, and bands of white and black) around 12 inches in length or more. Some of my hatchlings have been 16 inches out of the egg. You are able to take the baby rodents from the start, black milks grow steadily, eventually reaching as long as 7 feet by 4 to 5 years of age (though lengths of 5 to 6 feet are more common). These are beefy snakes. 

The largest milk snake, with a size "reaching 60 inches." Because of their size, black milks need large cages. Racks won't work. These are not overly active snakes, but I believe it is unhealthy to keep them in anything smaller than a cage with less than 6 square feet of floor space - this would be equal to a cage measuring 3 feet long, 2 feet wide, and 1 to 2 feet tall. Bigger is always better. Any of the commercially available plastic cages work fine, so long as they have a locking device to secure the sliding or hinged doors.

Black milks are a montane species and therefore have some special requirements regarding temperature, but these requirements actually make them easier to keep. Black milks like it cool Ambient cage temperatures in the low to mid 70s Fahrenheit. Black milks benefit from a warm basking spot when the ambient high temperature in the cage is 70 or lower. My basking spot, which uses a 50-watt infrared bulb, gets about 85 degrees. I only have the light on for about four to six hours in the morning if needed.

My schedule for heating a black milk cage varies by season and is as follows:

Winter: No heat for adults, room temperature set to 58 degrees.

Spring: Basking bulb on for four to six hours when the room temperature is below 70 degrees.

Summer: Ambient temperature about 72 to 78 degrees. No basking light needed.

Fall: Basking bulb on for four to six hours when the room temperature is below 70 degrees.

Avoid temperatures above 80 degrees. Always provide a cool retreat area. Kardon said the display at the San Antonio Zoo kept its black milks in the "cool room" with daytime highs of 72 to 73 degrees and nighttime lows as cool as 56 degrees. The basking lights were kept on for no longer than seven hours.

Black milks do well on a variety of substrates so long as you provide a cool, moist hidebox. Cypress mulch is probably the best substrate, as it does well in high-humidity setups and resists mold growth. You can also use shredded aspen, soft paper pulp products such as Carefresh, or even newspaper. The key, especially when using these drier substrates, is to provide a moist hidebox. I use a 12-quart plastic box with a hole cut in the lid. I stuff the box with moistened - not wet - sphagnum moss. This also doubles as an egg-laying chamber for females during breeding season. Without the moist hidebox, black milks can develop shedding problems. Obviously, avoid cedar, as the oils are toxic to all snakes.

Feeding black milks is about as trouble-free as you can get. 9 times out of 10, hatchlings will take a large frozen/thawed pink after their first shed. As adults, black milks will take small- to medium-sized frozen/thawed rats. It's best to offer two smaller rats rather than one larger one. Feed hatchlings once a week. Adults do well feeding every seven to 10 days, but feed females a bit heavier during breeding season, especially if you plan to double-clutch them. Sometimes, black milks take frozen/thawed rodents aggressively, meaning they will pounce. Feeding time is about the only time you don't want your hand near a black milk's mouth. They like to eat! Always provide a source of clean, fresh water. The water bowl does not need to be big enough for a soak.