Texas Indigo Snake

They’re very popular in southern/central Texas, where they primarily live. Texas indigo snakes are known for actively hunting and eating rattlesnakes. Diurnal by nature, they spend their nights in the burrows that other animals abandon.

These snakes mate in the winter and then lay eggs in an abandoned burrow in the spring. They lay 3-12 eggs, and hatchlings appear in the summer and measure 14-18 inches, but can reach 24 inches. They’re one of the longest species in North America and regularly reach 6-8 feet long; there have been reports of snakes approaching 10 feet, but they haven’t been verified.

They range from central Texas extending into northern Mexico, and until recently, Texas indigo snakes were on the protected list in Texas.

Amazing Facts About Texas Indigo Snakes

• They appear to be at least partly resistant to rattlesnake venom.
• Terrific to have around if you have venomous snakes nearby.
• They’ll eat anything they can overpower; birds, lizards, turtles, snakes, and rodents are all on their varied menu.
• They subdue their prey using brute force but are surprisingly docile.

Where To Find Them

These snakes inhabit areas with permanent water sources and grasslands, brush, or forests in Texas south of San Antonio, and into northern Mexico.

They spend their downtime in abandoned burrows and underneath logs and other items large enough to hide them, but Texas indigo snakes are active hunters and spend most of their time hunting during the day.

Scientific Name

Texas indigo snakes (Drymarchon melanurus erebennus) are nonvenomous colubrid snakes — active predators, not constrictors like boas. Their scientific name, Drymarchon, roughly translates to “Lord of the Forest,” while melanurus is a Greek term meaning “black.”

All of the indigo snake species have smooth, very shiny scales that reflect an iridescent blue-purple in the light, giving them their common name.

Types of Indigo Snakes

Until recently, all indigo snakes were classified as subspecies of Drymarchon corais; even some of the government sites still reflect this. However, genetic research revealed that there are five separate species; given more time and research, we may discover more.

Two of them occur in North America:

• D. melanurus erebennus mainly lives in South Texas and northern Mexico. It is primarily black but has some brown speckling.
• D. couperi Eastern indigo snakes live in the southeastern United States.

Two indigo snake species inhabit Central and South America:

• D. caudomaculatus lives in Venezuela and Colombia and has more brown speckling than its northern cousins
• D. margaritae inhabits the Western Margarita Islands and Venezuela.

History and Evolution

Like other snake species, the Texas Indigo Snake’s predecessors were also reptiles, but they had legs. These animals were more aquatic-based. Snakes either lost their legs or became vestigial, as snakes relied on them less and less. It is interesting to imagine animals evolving to have legs and then evolving to lose them! These snakes adapted to living as low to the ground as they could to avoid enemies and be closer to their prey.

These particular snakes adapted to being very good at killing other snakes and other smaller animals. In the wild, competition from other species leads to a few different outcomes over a long period of time. Extinction happens when an animal species is not able to adapt and overcome said competition. In this snake’s case, the outcome was to become stronger than other snakes in its area and even develop resistance to their venom.

Population & Conservation Status

For such a popular and well-loved snake, there’s a surprising lack of formal research into their population numbers, stability, and lifespan in the wild. We don’t have an accurate population estimate, and we can guess that in the wild, they might live about 9 years. Texas indigo snakes are state-listed (Threatened) — collecting or possessing them from the wild without the proper TPWD permit is unlawful. Contact TPWD for the exact permit requirements.

However, Texas indigo snakes still face challenges due to human encroachment. Each individual needs a large territory in which to thrive, but it is fairly flexible as long as there is a permanent water source nearby. They tend to favor somewhat dry grasslands and scrub brush. However, urban sprawl is reducing the amount of territory available, and many indigo snakes end up on the road, victims of a vehicle encounter.

Appearance and Description

Texas indigo snakes are large-bodied, very long, nonvenomous snakes with a base color of iridescent black scales and brown speckles. Their belly is often salmon-colored, becoming more cream-colored approaching the throat, and more blue-black towards the tail. They have black vertical bars that begin under their eyes and extend down to their labial (lip) scales. In fact, seeing dark vertical bars along the lip scales is one sign that a North American snake is not venomous, although this doesn’t hold true on other continents.

Hatchlings appear in the summer and can reach 2 feet long; there have been sightings of Texas indigo snakes nearly 10 feet long, but they’re not verified. Juveniles are often solid black but develop adult colors as they mature between the ages of 2-3.

How Dangerous Are They?

These snakes are generally docile and not aggressive. However, those who handle or harass a Texas indigo snake may discover its powerful bite. It may also release a foul-smelling musk from its cloaca and even rattle its tail.

Texas Indigo Snakes are well known as rattlesnake control and are loved by Texas farmers and ranchers. They are not aggressive, and as a result, are easy to observe from a respectful distance. There are multiple videos available that demonstrate their prowess as rattlesnake hunters; in a few of them, you can see the rattlesnake biting (and probably envenomating) the Texas indigo snake but still losing the battle.

Behavior & Humans

Texas indigo snakes are supremely helpful and feed on many of the animals that humans find a nuisance or, in the case of venomous snakes, dangerous. However, they need a large territory in which to hunt, and they are frequently run over by vehicles when crossing the road.

A Texas indigo snake will eat nearly anything it can overpower using its size and strength; in addition to venomous snakes, its menu includes non-venomous snakes such as coachwhips, small mammals, lizards, turtles, and birds. They’re really not all that picky. According to an article in the Naples News, “One specimen alone had three mice, two Mexican burrowing toads, and two juvenile snapping turtles in its stomach contents.”

These snakes were respected in southern Texas for rodent and rattlesnake control. So much so that many families previously kept them as pets around the yard to keep rodents and venomous snakes away.

Legal Note

Important: The Texas indigo (Drymarchon melanurus erebennus) is a state-listed species in Texas. Collecting, possessing, or selling wild individuals without TPWD authorization is illegal. If you’re considering an indigo as a pet, contact TPWD first and insist on legally documented captive-bred provenance.