Full Grown Black King Snake: Size, Lifespan, Price & More

The black king snake is a non-venomous colubrid snake species found across eastern and central North America. As it grows from a juvenile to an adult, the black king snake undergoes significant physical and behavioral changes. This guide covers everything you need to know about caring for a fully grown black king snake.

Size at Full Growth

Black king snakes reach sexual maturity at around 2-3 years of age. At this point, they are considered fully grown adults. On average, adult male black king snakes will grow to be 2-4 feet long while adult females are generally a little larger at 2.5-4.5 feet.

In terms of height, most full grown black king snakes will measure 1-2 inches wide at their widest points. So while they may not be the longest of snakes, they have thick, muscular bodies well suited to their prey restraint tactics.

Weight at Full Growth

When it comes to weight, males typically max out at around 1-2 pounds as adults while females tend to weigh slightly more at 1.5-3 pounds on average. The heaviest documented wild black king snake was a female that weighed 3.2 pounds.

Appearance at Full Growth

Visually, the black king snake undergoes few changes in color or pattern from juvenile to adult stages. Fully grown specimens will retain their namesake jet black dorsal scales with a contrasting cream or white ventral surface.

One notable change is that adult black king snakes tend to develop a glossier, thicker skin and more angular head shape compared to juveniles. Their jet black color also becomes more refined and intense as they age.

Personality at Full Growth

In terms of temperament, adult black king snakes are generally slower-moving, more sedentary snakes when compared to juveniles. They have also had more time to acclimate to handling, so mature specimens tend to be calmer, more tolerant of humans.

However, fully grown individuals also have a more set-in-their-ways personality and less tolerance for sudden movements or perceived threats. Proper socialization is still important to maintain a confident, easy-to-handle adult black king snake.

Price

On the exotic pet market, fully grown black king snakes typically sell for $50-150 depending on size, gender and other factors. Males tend to be a bit cheaper while large, proven breeders can fetch higher prices.

It's generally more economical to purchase a juvenile and raise it yourself, as hatchlings are often $20-50. This allows you to establish a strong bond and socialize the snake from a young age.

Food/Feeding

The dietary needs of adult black king snakes do not greatly differ from juveniles. In the wild, they hunt a variety of small prey like mice, frogs, lizards, and snakes. In captivity, fully grown specimens can be fed adult mice or small/medium rats once every 5-10 days.

It is important not to overfeed adult black king snakes to avoid obesity or digestive issues. Feed prey items that are about as wide as the snake's widest point. Remove any uneaten rodents after 30-60 minutes to avoid aggression or regurgitation.

Lifespan

With high quality care, black king snakes have an average lifespan of 10-15 years in captivity. Some individuals have been documented to live as long as 20 years. Factors like stress levels, health issues, and genetics play a role in maximum lifespan potential.

Health at Full Growth

When kept in ideal conditions with a proper diet, housing, temperatures and regular husbandry, adult black king snakes are generally quite hardy and healthy snakes with few ailments. However, there are a few health issues that can potentially affect fully grown individuals:

• Obesity from overfeeding - Monitor weight and food intake closely to avoid.
• Metabolic bone disease from calcium/vitamin D3 deficiency - Ensure a calcium rich diet and proper heating/lighting.
• Respiratory infections - Provide ambient humidity above 40% to avoid.
• Mites or ticks - Inspect for parasites and treat promptly if seen.

Care and Nutritional Needs at Full Growth

In terms of care requirements, adult black king snakes have similar needs to juveniles with a few small adjustments:

• Housing - Provide an escape-proof, secure enclosure no smaller than a 20 gallon tank for an average sized adult.
• Substrate - Use substrate like aspen shavings that allows burrowing/digging and holds humidity.
• Decor - Add branches, foliage, hides on the warm and cool sides for coverage.
• Temperature - Maintain a warm side of 88-92°F and cooler side of 80°F or slightly below.
• Lighting - Full spectrum lighting like a mercury vapor bulb is recommended 8-12 hours daily.
• Humidity - Keep ambient humidity between 40-60% with lush substrate and water bowl.
• Calcium and vitamin supplements - Provide a whole prey diet with supplements 1-2 times weekly.

Costs

The costs of caring for a fully grown black king snake are relatively low compared to other pet reptiles. Basic estimated monthly expenses include:

• $15-30 - Housing (20-30 gallon terrarium or enclosure)
• $10-15 - Heating/lighting supplies (bulbs, thermostats, fixtures)
• $10-20 - Substrate (aspen shavings, Eco Earth, potting soil)
• $5-10 - Decor (hides, plants, branches)
• $5-10 - Food (one pack of mice or small rats monthly)
• $10-20 - Calcium/vitamin supplements

So for a high quality setup and care, plan to budget around $50-100 per year on average to care for a fully grown pet black king snake after the initial setup costs.

Possible Behavioral Changes of a Fully Grown Snake

As black king snakes reach sexual maturity, a few minor shifts in temperament and behaviors may occur:

• Reduced activity levels and slower, more sedentary movements
• Increased defensiveness of territory and less tolerance of quick motions
• Yearly breeding season behaviors like roaming/searching in males or being easily startled in females
• Occasional testing/striking out of overconfidence if mishandled after years of socialization

In general though, black king snakes remain docile pets for life with consistent positive reinforcement training from a young age.

Notable Characteristics of a Fully Grown Snake

Some particular attributes that define a mature black king snake include:

• Refined jet black dorsal color and high contrast with cream undersides
• Thick, glossy skin texture rather than the duller juvenal skin
• Proportionately thick body size and robust musculature
• Mature, angular head shape rather than the round juvenal head
• Slower, more calculated movements rather than erratic juvenal writhing
• Calm, tolerant demeanor with steady tempered disposition
• Sexual maturity and readiness to breed each spring season

Final Thoughts

With their attractive jet black coloration, docile temperaments and affordable care, black king snakes make wonderful pets for experienced reptile owners. By understanding the specific needs of fully grown adult specimens, you can ensure your new snake thrives with optimal nutrition, housing and husbandry for many enjoyable years to come.