Timber Rattlesnake Dangers (with Bite, Venom, and Disease Facts)

All across the wilds of the eastern United States, the timber rattlesnake roams. This snake is known for its dark banded appearance, its iconic warning rattling sound, and its dangerous venomous bite.

A timber rattlesnake can grow up to 6.25 feet long, with average lengths between 3 and 5 feet. Its fangs are between 2.6 and 3.8 millimeters long, and its venom contains hemotoxins and neurotoxins. This venom causes a range of harmful effects on humans. Timber rattlesnakes face many dangers in the wild, including snake fungal disease.

It is important to understand the dangers a timber rattlesnake presents. At the same time, it is almost as important to learn about the diseases and other dangers which harm timber rattlesnakes, so that you can help protect these amazing creatures. Here we learn about it all.

How Dangerous Is a Timber Rattlesnake?

A timber rattlesnake has a dangerous bite with venom that is very harmful to humans. However, the timber rattlesnake is not a very aggressive species. It would rather safely leave your presence than bite you.

This snake is an essential factor in controlling rodent populations. Read on to learn about the timber rattlesnake, what dangers it poses to humans, and what dangers the timber rattlesnake itself faces.

Identifying a Timber Rattlesnake

Let’s start with some basic timber rattlesnake stats and information:

  • Scientific Name: Crotalus horridus
  • Adult Length Range: 3 to 5 feet
  • Adult Weight Range: 1 to 2 pounds
  • Average Weight Males: 2 pounds
  • Average Weight Females: 1.3 pounds
  • Record Length: 6.25 feet
  • Hatchling Length Range: 7 to 15 inches
  • Average Clutch Size: 6 to 10 eggs
  • Record Clutch Size: 20 eggs
  • Average Gestation Period: 135 days
  • Fang Length: 2.6 to 3.8 millimeters
  • Average Lifespan: 30 years
  • Record Lifespan: 40 years or more

What Does This Rattlesnake Look Like?

The timber rattlesnake species has a lot of color variations, but the 2 most common patterns are known as the black morph and the yellow morph.

In the black morph, the timber rattlesnake has gray scales with dark black bands and patches. In the yellow morph, the timber rattlesnake has tan scales with yellow-brown bands and patches.

As a hatchling, a timber rattlesnake will have similar colors to the skin it will have as an adult, though it may be a bit grayer in color. After its first shedding period, the juvenile timber rattlesnake will gain the first piece of its iconic rattle at the end of its tail.

A male timber rattlesnake is heavier than a female. The male usually has a much longer tail than the female as well.

Where Does This Rattlesnake Live?

The territory of the timber rattlesnake ranges across the eastern United States. They are found along the coast from New England to northern Florida, and as far west as eastern Texas and Minnesota.

A timber rattlesnake makes its home in forests, rocky hills, and swamps. It prefers dens in the cracks and crevices of rocky cliffs.

When Is This Rattlesnake Active?

The timber rattlesnake prefers warmer weather and so it is most active during warmer months. In the summer, a timber rattlesnake will migrate to find prey to hunt. During the winter, this rattlesnake will undergo brumation in a den with up to 60 other snakes.

Timber Rattlesnake Bite Facts

The main danger which a timber rattlesnake poses is its bite. If you hear a timber rattlesnake rattling its tail, your best choice of action is to turn around and walk away.

Timber Rattlesnake Teeth

Like other rattlesnakes, the timber rattlesnake has solenoglyphous teeth. These teeth feature two hollow fangs at the front of the jaw. The rattlesnake’s fangs are attached to a kind of hinge in the mouth, and so they can rest against the roof of the snake’s mouth, folded safely away. This makes it so the snake does not accidentally bite itself.

When a timber rattlesnake bites into its prey, its fangs unfold and come down onto the prey animal. These fangs are hollow and connected to venom glands. The timber rattlesnake can use these fangs to inject a high amount of venom quite rapidly.

The timber rattlesnake may leave behind one or two puncture marks from its fangs after a bite.

What Does This Snake Eat?

A timber rattlesnake is a carnivore that eats terrestrial vertebrates. It mainly eats small animals, such as rabbits, squirrels, rats, and mice. The timber rattlesnake is essential for keeping populations of pests, such as rodents, under control. On occasion, this rattlesnake will also eat birds, frogs, and even other snakes.

The timber rattlesnake will inject its prey with venom and then wait for its prey to die. Once the prey is dead, it will swallow its prey whole.

How Likely Is a Rattlesnake Bite?

On the whole, a timber rattlesnake is not a very aggressive animal. A timber rattlesnake does not see a human as prey and so is not inclined to bite us unless it needs to defend itself.

A timber rattlesnake is more likely to try to hide or flee if it hears or smells a human coming. It may also try to scare away the human with a defensive threat display. Biting is a last resort.

Timber Rattlesnake Threat Display

If provoked, a timber rattlesnake will not immediately bite. Its first response is to perform a threat display. This behavior includes lifting up its body from the ground, forming an S-shape with its head and neck. The snake will also hiss at the threat, vibrating its tail to create the distinctive rattling sound that rattlesnakes are famous for.

The timber rattlesnake may then seek an escape route. If there is no way to easily flee and the threat does not back off, then the timber rattlesnake will strike and bite the threat.

Timber Rattlesnake Venom Facts

When a timber rattlesnake bites down, its fangs inject a powerful venom into its victim. This venom is toxic to humans. Let’s learn more about this rattlesnake’s venom and the consequences of getting bitten.

timber rattlesnake behavior

What Kind Of Venom Is It?

Different snake venoms have different effects on the human body. According to BMC Genomics, the exact composition and effects of a timber rattlesnake’s venom vary depending on the individual snake.

Timber rattlesnake venom contains neurotoxins and hemotoxins. Along the northern edge of timber rattlesnake territory, you are more likely to find a timber rattlesnake with more hemotoxins in its venom. Along the southern edge of its territory, the timber rattlesnake has more neurotoxic venom.

This variety in venom composition results from different timber rattlesnake populations eating slightly different prey and fending off slightly different predators. If natural selection favors neurotoxins over hemotoxins to slow down prey, those snakes will survive and breed. This makes neurotoxic venom more prevalent through natural selection.


Hemotoxic venom alters the body’s ability to coagulate blood. When a human is wounded, the blood will usually clot itself to keep you from bleeding to death.

The hemotoxins in a timber rattlesnake’s venom prevents coagulation. It also reduces platelet numbers, making it difficult for the body to close up other wounds later. Hemotoxins keep the bite wound from healing and in severe cases will cause internal bleeding and hemorrhaging.

Hemotoxins also cause necrosis, or cell death. This may result in the skin around a timber rattlesnake bite appearing blackened.


Neurotoxic venom attacks the victim’s nervous system. It uses chemical signals to prevent neurons from communicating with each other.

Communication between neurons is how the human body’s muscles know how and when to function. Disrupting that communication can cause muscle spasms and paralysis. It can also lead to difficulty breathing or cardiac arrest.

Timber Rattlesnake Envenomation Symptoms

Early symptoms of envenomation after a bite may include the following:

  • Pain and swelling in the affected limb
  • Bruising or discoloration around the bite
  • Numbness in the affected limb or in the face
  • Lightheadedness or weakness
  • Nausea or vomiting
  • Sweating
  • Blurred vision
  • Difficulty breathing

Why Do Timber Rattlesnakes Have Venom?

Venom is basically the timber rattlesnake’s saliva. However, this is saliva that performs multiple useful tasks for the snake’s survival.

A timber rattlesnake cannot hold onto its prey effectively. It only has its mouth to grab with, lacking any hands or claws. If it does not kill its prey with one bite, then the prey may fight back and hurt the snake.

Timber rattlesnake venom allows the snake to bite and release its prey. The venom will affect the prey and slow it down. The hemotoxins in the venom will prevent the wound from closing, giving the timber rattlesnake a trail of blood to follow. The neurotoxins in the venom will cause the prey to weaken and become paralyzed, quickly collapsing so that the snake can catch up and eat.

The venom also works to begin digesting the prey before the snake has even swallowed it. Digestion is a long process for a timber rattlesnake. It does not chew its food; rather, this snake swallows its meals whole. Timber rattlesnake venom beings to break down the prey much like chewing would, helping the snake to digest its meal.

Venom is also the timber rattlesnake’s primary defense against threats. Any would-be predator knows that a snake which makes that iconic rattling sound should not be messed with.

Curing Timber Rattlesnake Venom

Timber rattlesnake venom can be counteracted with antivenom. Antivenom for timber rattlesnake bites is widely available at hospitals, especially in areas where timber rattlesnakes are known to live.

Timber rattlesnake antivenom is made from the venom itself. When administered to an envenomated patient, the antivenom stops the effects of hemotoxins and neurotoxins.

When Antivenom Is Not Enough

Antivenom successfully stops the progression of a timber rattlesnake’s venom’s harmful effects. However, it does not repair all of the damage that the venom caused to the victim’s body. At this point, further medical treatment will be necessary.

Here are some examples of the harmful effects of timber rattlesnake venom which antivenom is not quite enough to fix.


According to the journal Annals of Emergency Medicine, antivenom treatment only cures some of the venom’s hemotoxic effects. Antivenom reverses the anticoagulant effects quickly and reliably, allowing the victim’s blood to begin clotting again.

However, the venom also causes thrombocytopenia – a reduction of platelet numbers in the victim’s blood. Platelets are another part of blood clotting. Antivenom treatment does not raise platelet numbers again, and so additional medical treatment after antivenom dosing may be necessary.

While the reason for this is unknown, it is possible that there is a factor in the venom which the antivenom does not neutralize, allowing the thrombocytopenia to persist.


According to the American Academy of Neurology, timber rattlesnake venom can often cause myokymia in the victim’s face or limbs. Myokymia is an involuntary quivering of muscles, not enough to move a limb but a motion which is out of the individual’s control.

As the venom attacks the victim’s nervous system, it increases the excitability of peripheral nerves across the victim’s body, causing this quivering or twitching motion.

After antivenom treatment, facial myokymia soon disappears. However, limb myokymia may persist after antivenom treatment. This amount of myokymia may require additional hospital treatment, such as applying a serum of ionized calcium.

Timber Rattlesnake Disease Facts

The timber rattlesnake does not spread diseases to humans. However, this snake is itself vulnerable to some diseases.

A big threat to timber rattlesnakes is snake fungal disease. According to Cornell University, the fungus was first discovered due to how it was harming populations of timber rattlesnakes in New Hampshire. Since then, snake fungal disease has been found to harm over 12 species of snake.

Snake fungal disease is transmitted when a timber rattlesnake comes into contact with an infected snake or the fungus itself. The snake will develop skin discoloration around the infection site. The fungus will gradually penetrate the snake’s skin, creating painful lesions.

These lesions can be on the snake’s face, making it difficult for snakes to catch and eat their prey. The fungus also gradually weakens the snake’s immune system, making a timber rattlesnake vulnerable to other diseases.

Sometimes the fungus is contained within the snake’s skin. Then the snake is able to shed its skin and with it get rid of the infection. However, if fungal stalks remain on the snake after the skin is shed, the infection will return. Snake fungal disease is often fatal to timber rattlesnakes.

Threat To The Timber Rattlesnake

Snake fungal disease is not the only threat a timber rattlesnake faces in the wild. According to Biological Conservation, the timber rattlesnake may be quickly approaching species extinction.

The timber rattlesnake is classified as an endangered species in 6 states and as a threatened species in 5 others. The main threat to timber rattlesnake numbers is human behavior. As humans expand cities and roads into natural habitats, the snake loses its territory and prey sources. Humans also tend to capture and kill the timber rattlesnake out of fear of its bite.

Local governments work to protect the timber rattlesnake by creating bans on the commercial sale of this snake, as well as banning people from making bounties on these snakes. State and national forests are also hard at work to conserve these powerful reptiles.

Why Care About The Timber Rattlesnake?

The timber rattlesnake is not just a danger. It is at risk as well. You may be wondering, why does this matter to us? If a timber rattlesnake is dangerous to humans, then why should we protect it?

Also, the timber rattlesnake is nature’s pest control. This rattlesnake feeds on rodents like mice and rats, which are common vectors of disease. Without the timber rattlesnake, we would be overrun with rodents. A timber rattlesnake is in this way an essential part of local ecosystems.

We encourage you to take this information about timber rattlesnake dangers to heart, so that you do not get harmed by their venom or bites. At the same time, be sure to appreciate this vital animal from a safe distance.

Photo of author

Lou Carter

Hi, I'm Lou. I’ve always been fascinated by snakes and reptiles. That’s why I set up snakesforpets.com – to answer every question that you could ever have about snakes as pets (and how they survive in the wild.) I hope that you find this website useful!

Cite this article:

MLA Style: Carter, Lou. "Timber Rattlesnake Dangers (with Bite, Venom, and Disease Facts)" Snakes For Pets, (December 15, 2020), https://www.snakesforpets.com/timber-rattlesnake-dangers/.

APA Style: Carter, L. (December 15, 2020). Timber Rattlesnake Dangers (with Bite, Venom, and Disease Facts). Snakes For Pets. Retrieved December 15, 2020, from https://www.snakesforpets.com/timber-rattlesnake-dangers/

1 thought on “Timber Rattlesnake Dangers (with Bite, Venom, and Disease Facts)”

  1. I live in Texas near a wooded area. My dog got bit in the face by a Timber Rattler. He went limp, unable to move, foaming at the mouth, defecated, in about 5 mins. Luckily I was there and got him to the vet within about 25 minutes. Also luckily, the vet had antivenom. It cost me around $2,200, but my dog was ok the next morning when I picked him up, other than a sagging lip where he got bit. If it were not for my other dog warning me, I would have gotten bit by the same snake. Be careful out there and keep your eyes on the ground when walking. Those things blend in with the terrain very well and are hard to see. I believe they breed in April and August, so especially keep an eye out around those months.


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