Keeping and Breeding Mexican Black King Snakes
The Mexican Black King Snake is a subspecies of the Common King Snake and naturally occurs in the Sonora Desert, Northwestern Sinaloa, Mexico and small parts of Arizona. The Mexican Black King Snake interbreeds with the Californian King Snake in parts of its range, these naturally occurring crosses are called intergrades. Doing this in captivity is frowned upon by most snake breeders. As its name suggests this King Snake is completely black in colour, even the eyes are black. Its smooth shiny scales give this snake a glossy appearance, which really compliments the black colouration. This snake grows to between 90cm -1.5m as an adult. Mexican Black King Snakes are easy to feed, easy to house, make great pets and are easy to breed which makes them an ideal captive snake. This article will discuss the captive care and breeding of this black beauty.
I keep adult Mexican Black King Snakes in 26 litre tubs in a rack system, they will do equally well in glass terrariums or wooden and glass display cages measuring 90cm x 45cm x 45cm. A hot spot of 28 -30 degrees Celsius is provided using heat cable or a heating pad controlled by a thermostat. Background temperatures are maintained at 25 degrees Celsius. During the height of summer these snakes can easily be kept at room temperature without supplemental heating. I use coconut husk as bedding, but any dry, nontoxic, dust free natural substrate could be used. Newspaper or paper towel can also be used as a substrate. Provide fresh water at all times and lightly spray your King Snake with water before it sheds to ensure it sheds properly. A hide box is essential and your snake will spend the majority of its time in its hide. Always keep King Snakes separately as they are cannibalistic.
In the wild Mexican Black King Snakes feed on lizards, rodents, nestling birds and other snakes including Rattle Snakes. In captivity these snakes will feed on frozen thawed mice their entire lives. Feeding live food is unnecessary as Mexican Black King Snakes readily accept dead prey from the time they are hatchlings. Feed your king snake an appropriately sized rodent once per week. Mexican Black King Snakes have a strong feeding response and can expect food every time the cage is opened resulting in a snake that ends up confusing your fingers for food. To avoid this feed your snake in a separate tub or use a snake hook to tap your King Snake on its snout when you open the cage for things other than feeding. The snake will learn that when it gets tapped on the snout it’s not feeding time and will calm down. Do not handle your snake for three days after it has eaten to avoid having to clean up regurgitated mice which is a very unpleasant experience.
In order to successfully breed Mexican Black King Snakes you will have to put them through a cooling period. This cooling period is called brumation. Start by increasing feeding in late April to give your King Snake the extra fat reserves it will need during brumation. In May keep your heaters on but cease feeding the snakes for at least 2- 3 weeks before you cool them down in order for the snakes to empty their digestive tracts. Any leftover food will rot in your King Snakes stomach during brumation which could lead to a deadly infection. In June drop your King Snakes cage temperatures to between 10-15 degrees Celsius for 2-3 months. The brumation temperatures can be slightly lower or slightly higher than this. My snake room has an average winter temperature of 12-17 degrees Celsius and my Mexican Black King Snakes brumated in this room bred successfully. In early September you can begin to slowly heat your King Snakes back to their summer temperatures. Do not heat your King Snakes up too quickly as this can affect your male King Snakes fertility. Offer your snakes a small food item a few days after warming them up. It is normal for males to refuse food during the breeding season. Feed females heavily to provide extra calories for egg production.
Female King Snakes will shed two weeks after they come out of brumation. This is called the post brumation shed and indicates that your female King Snake is ready to mate. I introduce the male King Snake into the female King Snakes cage. Mating behaviour usually starts immediately and the male will mate with the female very soon after introducing them if the female is receptive. Mating can last for a few minutes to a few hours. Separate your King Snakes after they have finished mating as one may attempt to eat the other. You can allow your King Snakes to mate more than once to increase the chance of fertile eggs.
Female Mexican Black King Snakes will go through a pre laying shed 4-6 weeks after successful mating. The female King Snake will lay her eggs 10-14 days after the pre laying shed. Females will stop feeding a few weeks before egg laying as the eggs don’t leave any space for food. Provide a laying box filled with moist sphagnum moss for your King Snake to lay her eggs in. The female King Snake will spend a lot of time in the egg laying box prior to laying eggs. Check the egg laying box daily for eggs. King Snakes can lay 6-20 eggs but clutches are usually smaller than 20. The number of eggs a King Snake will lay is dependent on the size of the female King Snake with larger females often laying more eggs. Once your King Snake has finished laying all her eggs you will need to move them into an incubator. If fed heavily enough Mexican Black King Snakes can lay two clutches of eggs a year.
Snake eggs have a leathery shell which absorbs moisture throughout the incubation period, therefore you need to incubate your King Snake eggs on a moist incubation medium. I place my King Snake eggs in a plastic container filled with a layer of perlite a few centimeters deep. The perlite is mixed with water at a ratio of 1 part perlite to 1 part water by weight. If your eggs start to dent during incubation you will need to add more water to the incubation medium. Vermiculite can also be used to incubate King Snake eggs. I do not put air holes in the incubation container as I have experienced small flies coming through the holes and causing the eggs to rot, but instead open the lid for a few minutes a few times a week to allow air in. It is very important not to turn snake eggs and you must keep them in the position that they were laid in otherwise the embryo will detach from the shell and die. Do not attempt to pull eggs apart from each other if they are laid stuck together. Incubate your King Snake eggs at 27-28 degrees Celsius. At this temperature they will hatch in approximately 60-65days. However the eggs can take up to 70-75 days to hatch if incubated at temperatures a few degrees lower. Incubating for longer at slightly lower temperatures will result in larger hatchlings.
Baby King Snakes are equipped with an egg tooth which they use to slit open the egg shell. When you see several slits appearing on your eggs it means they are hatching. Eggs will also dent slightly when they are about to hatch. You will eventually see the baby King Snakes poking their heads out of the eggs. It can take several days for the entire clutch to hatch. Do not attempt to remove the baby King Snakes from the eggs, allow them to hatch on their own. Once the King Snakes have hatched remove them from the incubation box and house them separately in individual plastic tubs.
Care of Hatchlings
Hatchlings should be housed separately in plastic tubs under the same conditions as adults. One of the biggest mistakes new snake owners make is to house tiny baby snakes in huge cages. Doing this will result in a snake which is unlikely to feed properly and it will most likely escape its large cage. Baby Mexican Black King Snakes can easily get through the gaps of the sliding glass in a wooden and glass display cage. Hatchling Mexican Black King Snakes will shed about a week after hatching do not offer them food until they have had this first shed. Feed your hatchlings a 1-3 day old pinky mouse every week. Some hatchlings may not feed straight away and can take a few weeks to start feeding. They usually have yolk inside for nourishment during this period. If your baby Mexican Black King Snakes refuses to feed you can try scenting the mouse with a lizard, feeding in a smaller container of cutting open a pre killed pinkies head.
Interesting Fact: Why Some Snakes are Black
You might ask why some snakes such as the Mexican Black King Snake are black in colour? It doesn’t aid in camouflage so what is the advantage of being black? Snakes, like all reptiles are ectothermic, which means that their body temperature will be exactly the same as their surroundings. Reptiles do have methods to increase or decrease their body temperature such as basking in the sun to increase body temperature and retreating to a cooler spot to decrease body temperature. So, what does this have to do which black colouration? Being black in colour allows a snake to absorb heat more quickly, as darker colours absorb heat better than lighter colours. The Mexican Black King Snake can therefore heat itself up much quicker after a cold desert night. European Adders and Eastern Garter Snakes which range into the Arctic Circle have completely black or melanistic ( an increase in black pigment ) populations which occur in the coldest regions of these snakes’ range, this allows these snakes to heat up very quickly.
So, next time you are at a reptile show, walk away from the many colourful snakes on display and check out a Mexican Black King snake. From the glossy black scales to the shiny black eyes, you won’t be able to resist adding one to your collection.