A Detailed Guide to King Rat Snake Breeding Techniques and Management Methods

The king rat snake is one of the snake species with relatively large populations among wild snakes. Because of its fast growth, abundant meat, strong cold resistance, and large seasonal price differences, it is currently one of the main targets of development and utilization in China. But no wild animal can withstand unlimited predatory hunting. It is suggested that development and utilization should be combined with captive breeding, so that it can be used by humans more fully and better.

1. What regional aliases does the king rat snake have? Where is it mainly distributed? The king rat snake is also known as the king snake, snake king, cauliflower snake, king snake, stinky yellow snake, prince-head snake, hemp snake, rapeseed flower, keeled rat snake, yellow python snake, vegetable python, and so on.

The king rat snake is mainly distributed in Zhejiang, Jiangxi, Anhui, Jiangsu, Fujian, Hunan, Hubei, Guangxi, Guangdong, Yunnan, Guizhou, Shaanxi, Henan, Gansu, and Taiwan, China, and other provinces (municipalities, autonomous regions). It is a typical non-venomous snake, and its growth rate is second only to that of pythons.

2. What are the characteristics and habits of the king rat snake? The main characteristic of the king rat snake is the black marking resembling the character “king” on its head, which is why it is called the “king snake.” The edges of the scales on its head and back are black, with yellow in the center, resembling a rapeseed flower. The front part of its body has more than 30 yellow diagonal transverse stripes, which gradually disappear toward the rear part of the body. The ventral surface is yellow, accompanied by black markings. The tail is slender, and the total length can reach more than 2.5 m. The color patterns of adult snakes and juvenile snakes differ greatly. Juveniles do not have the “king”-shaped marking on the head, and are often mistaken for other snake species.

The body of the king rat snake is cylindrical, and large individuals can reach more than 5-10 kg. It mainly lives in hills and mountains, and also inhabits riversides, reservoir areas, and fields in the plains. It is agile, relatively fierce in temperament, crawls quickly, and can climb rocks and trees. It mainly feeds on rodents, frogs, birds, and bird eggs, and may even cannibalize its own kind when food is scarce. This snake has a peculiar stench on its body. After holding the snake, one must wash several times with strongly scented soap before the odor can be removed. This snake reproduces by laying eggs, laying eggs from June to July each year, with 8-15 eggs per clutch, and the incubation period is about 40-45 days.

3. How does the king rat snake differ from other snakes? At present, there are still not too many non-venomous snakes in China that are completely suitable for artificial breeding, and the king rat snake is one of the good varieties among them. Because of its many advantages, such as large body size, cold resistance, broad feeding habits, strong adaptability, fast growth, short rearing cycle, ease of raising and incubation, and high market price, many snake farms or snake breeders, especially in the provinces (regions) north of the Yangtze River, mostly choose it as the preferred non-venomous snake to raise. From 1996 to 2001, the price of the king rat snake remained at the top among many non-venomous snakes, which is also the main reason people raise it.

Although the king rat snake is the fastest-growing and larger-bodied snake among non-venomous snakes (except pythons), it has a fierce temperament, dares to compete for food with venomous snakes such as the five-paced pit viper and the cobra, and has the habit of cannibalizing its own kind or other snakes. Therefore, this snake can only be raised separately and cannot be mixed with other non-venomous snakes in the same facility. When raising this snake, even if the feed provided is abundant and varied, a certain amount of feeder snakes should still be provided irregularly, such as the red-spotted snake, twin-spotted rat snake, water snake, and so on, to satisfy its snake-eating “habit” and avoid the phenomenon of snakes eating one another. This is the main way it differs from other snakes.

4. How is the growth of the king rat snake? Under suitable conditions, the king rat snake grows very quickly, unmatched by other snake species. Take the king rat snakes raised in my snake garden as an example: in the spring of 1994, we introduced a batch of king rat snakes weighing about 700 g each. One of them grew especially fast, which attracted the special attention of the keeper. Before winter that year, it was caught, weighed, and recorded. At that time it weighed 1500 g, a net gain of 800 g that year; in the second year it gained 1200 g; in the third year it surged by 1500 g; in the fourth year it gained only about 700 g. Over 4 years, this snake gained an average of 1100 g. Although this is only an individual case, it is an indisputable fact that the king rat snake indeed gains weight faster, is easier to raise, and offers higher returns than other snakes.

Because this snake was too large and too fierce, and later mainly swallowed other snakes and was not interested at all in the feed provided, it seriously endangered the snakes in the same facility and became the true “snake king” in the snake garden. Helplessly, in the early winter of 1998, it was sold reluctantly for 880 yuan. For this reason, the author suggests: if raising king rat snakes, there is no need to feed them to such a large size. It is just right to sell them when they reach about 700-1000 g. Because the king rat snake, like other snakes, grows in stages. Once it reaches a certain weight range, growth shows a state of slow weight gain, as can be seen from the growth description above.

5. What are the rearing density and feeding conditions of the king rat snake? The average rearing density of the king rat snake should be about 7-10 snakes of about 500 g per sq m. If larger individuals are introduced, 2-4 fewer can be kept per sq m; under three-dimensional rearing conditions, 15-25 can be kept per sq m. Newly introduced king rat snakes, because they are unfamiliar with the new environment and have difficulty adapting in a short time, may become very timid. Some even hide in the nest during the day and come out to seek food only at night, and only after a long time do they dare to come out and move around during the day (about 5-10 days). But the vast majority of king rat snakes are bold and not afraid of people; even if someone is nearby, it does not hinder them from swallowing food. The king rat snake eats more than other snakes. One weighing about 1000-1400 g can swallow 1-2 toads or 2-3 chicklets in succession at one time. After eating its fill once, it crawls back to the snake nest and lies still, and digestion takes about 7-15 days. If conditions permit, it is best to provide some feeder snakes regularly to satisfy its preference for eating snakes and avoid cannibalism. In addition, the king rat snake also eats chicken eggs or quail eggs, so it is worth feeding some when food is lacking to relieve the immediate need.

6. What reproductive characteristics does the king rat snake have? The king rat snake reproduces by egg-laying, with the peak egg-laying period from the end of June to mid-July each year, laying 5-15 eggs per clutch. Freshly laid eggs have mucus on the surface and often several stick together. When an egg is broken open, it can be found that there is no distinction between yolk and albumen inside; all is pale yellow gelatinous material. The eggs of the king rat snake are relatively large, round or oval, milky white, each weighing about 40-55 g, with smaller eggs also weighing 30-38 g, and the incubation period is as long as about 40-45 days. According to observation, after laying eggs, the king rat snake coils over the eggs, seemingly showing egg-guarding behavior. But in artificial breeding of the king rat snake, what is valued is still artificial incubation. The egg incubation technique for the king rat snake is the same as for other snakes, only the number of incubation days differs. Artificial incubation of king rat snake eggs mostly uses the jar incubation method. The optimal temperature for snake egg incubation is 20-30°C. If the temperature is too low, the incubation time will be prolonged; if the temperature is too high, although the incubation period can be shortened, it is easy to produce deformed juvenile snakes.

7. How do juvenile snakes differ from adult snakes? Newly hatched juvenile snakes have a body length of 25-35 cm, with a few large ones reaching 35-45 cm. Their body color is lighter, and there is no “king”-shaped marking on the head, often leading people to mistake them for other snake species. Juvenile snakes have 2 short black longitudinal stripes on the occipital region, and the back is light tea-brown with irregular fine small black markings; the tail back has 2 fine black longitudinal stripes extending to the tail tip; the rear part of the body and both sides of the tail each have 1 row of black dot-like markings; the ventral surface is light red, and both sides of the ventral scales have black dot-like spots. From the above description, it is not difficult to see that from the pattern and color of juvenile snakes, the appearance of adult snakes cannot be found at all. The difference is so great that it is hard for beginner keepers to believe that these are juvenile king rat snakes. This phenomenon is also very rare among many snake species.

8. How should juvenile snakes be raised? Juvenile snakes shed their skin for the first time 7-10 days after hatching. For artificial rearing of juvenile snakes, snake breeders (farms) with conditions may adopt a crossover method of early force-feeding and later provision of live prey. During artificial force-feeding, start by feeding only fresh egg liquid, and later add some small insects mashed into meat paste, such as crickets, grasshoppers, yellow mealworms, fly maggots, and so on, to lay the foundation for juvenile snakes to actively prey on live animal feed later. During this period, some live small water snakes, loaches, crickets, locusts, grasshoppers, and so on may also be provided for juvenile snakes to prey on automatically. The feeding time should be based on the juvenile snakes finishing the food within 24 hours, and at that time all uneaten food or food killed by the juvenile snakes should be removed. Normally, do not feed in scattered small amounts, so as to whet the appetite of the juvenile snakes, cultivate a good habit of eating on schedule, stimulate their desire to actively prey, and lay the foundation for normal rearing later.

9. How is the feeding cycle of juvenile snakes calculated? Usually, once a juvenile snake actively preys and eats its fill, it does not need to be fed again within 5 days. Feeding should begin after the 5th-7th day, and thereafter once about every week. This feeding frequency can remain unchanged until the period before hibernation. However, the size of the prey can gradually increase, and the amount of feed must reach 4-5 times the number of juvenile snakes. Feeder snakes smaller than the juvenile snakes should be provided regularly, so that from an early age they develop the good habit of not cannibalizing their own kind.

10. How should the temperature required by juvenile snakes be controlled? In general, the suitable temperature required by juvenile snakes is basically similar to that of adult snakes, but the range of temperature adaptation for juvenile snakes should be slightly higher. Juvenile snakes hatch in August-September, when the surrounding natural environmental temperature can meet their living and growth requirements. If the temperature is below 20°C, measures for keeping warm or raising the temperature should be taken; if the temperature is above 35°C or has been above 32°C for several consecutive days, measures for shading or cooling should be taken. This is because the most suitable rearing environment temperature for juvenile snakes is 23-28°C. Short-term low or high temperatures do not greatly harm juvenile snakes, but one should not be careless and leave them unattended.

11. How should the humidity required by juvenile snakes be controlled? For juvenile snakes, it is more suitable to keep the relative humidity of the rearing site at 40%-50%. When juvenile snakes enter the shedding stage, their demand for environmental humidity is higher and should be kept at 50%-70%. If the environmental humidity is too low, the dry climate is not conducive to shedding by juvenile snakes, and they often die because they cannot shed their skin. However, environmental humidity should not be too high either, and generally should not exceed 75%. Although short-term high humidity has little effect on juvenile snakes, over a long time juvenile snakes are prone to mold spot disease. Under conditions of poor air circulation, juvenile snakes are prone to pneumonia. Therefore, ventilation should be strengthened to keep the air in the rearing site fresh.

12. What should be noted in winter rearing of juvenile snakes? In order to obtain greater economic benefits or to master new techniques for off-season rearing of juvenile snakes and further lay the foundation for large-scale snake breeding, snake farms with conditions often break the hibernation period of juvenile snakes to make them grow as quickly as possible. Because the king rat snake has relatively strong cold resistance, along with advantages such as a wide food source, strong plasticity for breeding, and high winter prices, it is one of the main snakes that people first included in winter rearing of juvenile snakes. However, it should be noted that breaking the hibernation period of juvenile snakes should preferably be done gradually and steadily. The specific method is to lower the temperature 10 days later in late autumn of the same year, so that the juvenile snakes enter hibernation 10 days later; in the following spring, raise the temperature 10-15 days earlier to force the juvenile snakes to emerge earlier from dormancy. Under no circumstances should the hibernation habit of juvenile snakes be broken all at once. After all, juvenile snakes differ from adult snakes, and their tolerance is not ideal. Blindly restricting their hibernation time can easily throw their normal growth pattern into temporary disorder, which is not conducive to the normal needs of juvenile snakes. If the hibernation time of juvenile snakes is shortened year by year and they are allowed a certain adaptability, then the goal of safely breaking juvenile snake hibernation, extending their growth time, and shortening the rearing cycle can be achieved. For snake farms (households) located south of the Yangtze River, because the hibernation time is shorter, the impact is not too great. Wherever rearing conditions can be met, one might as well simply let the juvenile snakes not hibernate.

13. How should the food for winter rearing of juvenile snakes be solved? Some people believe that juvenile snakes in the first year can be directly winter-reared because they do not have hibernation adaptability. That is, winter rearing of juvenile snakes can be carried out only when the required temperature and humidity conditions can be met and the food source can be guaranteed. At the same time, in order to obtain sufficient live small animals in a timely manner, one might as well cultivate or temporarily keep (store) live bait such as earthworms, crickets, white mice, loaches, and small miscellaneous fish, and may also use eggs from self-raised quail and partridge to feed juvenile snakes. When necessary, some high-nutrition liquid feed may be force-fed. White mice have strong reproductive capacity and are easy to raise, so they can be appropriately introduced and then used to feed juvenile snakes after breeding. In addition, breeding crickets in a greenhouse is also a good method. Place some bran, fruit peels, and vegetable leaves in an idle greenhouse, pile up some bricks or tiles, and put in the “house crickets” often found in the corners of kitchens. After some time they will multiply in large numbers, and then they can be caught regularly to feed juvenile snakes.

14. What should be noted when using snake boxes for winter rearing of juvenile snakes? If you want to use snake boxes for a small-scale trial of winter rearing juvenile snakes, you can use the method of hanging 1-3 60-100 W incandescent bulbs from the top inside the snake box to raise the temperature. However, the outside of the bulbs must be covered with a shade so that the juvenile snakes cannot directly touch the bulbs. For box rearing or pool rearing in a slightly smaller snake house, methods such as soil heating, radiator heating, or electric stove heating with a gentle fire can be used. If conditions permit, using an air conditioner to control the temperature is of course the most ideal, but open flames (stove fire or wood fire) should not be used for direct baking and heating, and care should be taken to prevent thick smoke from choking the juvenile snakes to death.

During the winter rearing period of juvenile snakes, in addition to maintaining normal temperature and humidity, the health or disease situation of the juvenile snakes should also be checked regularly, and problems should be solved as early as possible. If unexpected circumstances arise that make normal rearing impossible, winter rearing of juvenile snakes should be terminated as early as possible and they should be allowed to enter hibernation.

15. What should be noted in free-range rearing of juvenile snakes? In the vast areas south of the Yangtze River in China, because the climate is suitable, the environment is humid, food is much more abundant than in the north, and juvenile snakes hibernate much later than in the north, free-range or semi-free-range rearing is relatively suitable. For juvenile snakes raised in free-range or semi-free-range form, it is best to adopt the method of concentrated scheduled and fixed-point feeding in an exercise yard or fixed location. In this way, over time, the juvenile snakes will become accustomed to this method. Especially when mainly feeding dead food, such as loaches, small miscellaneous fish, or quail eggs, even more attention should be paid to the feeding location. At that time, the uneaten feed should be thoroughly removed to prevent spoilage and bacterial spread that directly endanger the health of juvenile snakes. If juvenile snakes are raised free-range indoors with good lighting conditions, in addition to doing a good job of preventing escape, the nests and holes for the juvenile snakes should also be built well, so that the juvenile snakes have an ideal and safe habitat.