Agkistrodon piscivorus, Crotalus horridus,
Sistrurus Miliarius

GENERAL INFO: There are several species of snake in Florida, many benign or a minor nuisance. However, the Florida Cottonmouth (Agkistrodon piscivorous), Eastern Diamondback (Crotalus Horridus), and the Dusky Pygmy Rattlesnake (Sistrurus Miliarius) are the most common venomous snakes in SW Florida. For this reason, it is important to be aware of these species. All three of these snakes are classified as pit vipers, called such for heat sensing pit organs located between their eyes and nostrils on either side of their heads. The Florida Cottonmouth, so named for its white lined mouth, is the world's only semi-aquatic viper (found swimming in shallow lakes, streams, and coasts), growing up to 6 feet in length. The Eastern Diamondback is the heaviest of venomous snakes in the Americas, often weighing in at over 30 pounds and up to 8 feet in length. The Dusky Pygmy Rattlesnake is very small by comparison, averaging around 12-24 inches in length, but is very thick bodied. All three species give birth to live young, capable of delivering venomous bites. Young snakes from all three breeds are in some respects more dangerous as they do not know how to control the amount of venom they inject in their bites, often delivering many times more venom than a normal adult bite.

THREAT: The most common problem caused by snakes is that they invoke fear in many people. Yes, there are a few venomous species. Most cause no serious threat unless provoked. However, a bite could be life threatening. If you or someone you know is bitten by a snake, even suspectedly, please call 911 immediately! There is also a Snake Bite Action Plan on our Resources page for reference. This action plan should not be used in lieu of contacting emergency medical services.

REMOVAL / PREVENTION: Snakes are around your property for a variety of reasons. Usually, if you can limit their food source, then you will limit snake activity on your property. In most cases the snakes need to be removed and relocated.

IMAGES: Click for larger image.


Physical Strength:*


Attack Speed*:


Health Threat:*

Property Threat:

Breeding / Propagation:**

*Darker green represents Dusky Pygmy Rattlesnake, lighter green the Florida Cottonmouth, lightest green the Eastern Diamondback. Colors are stacked - for instance, the Pygmy snake is the least resilient snake, followed by the Cottonmouth, then the Diamondback.

**Eastern Diamondbacks leave their brood to fend for themselves leading to a high mortality rate for their young.



x 6-12 annually for all three breeds.


Eastern Diamondbacks held in captivity can live longer than 20 years!

Florida Cottonmouths are good swimmers and have been observed crossing the sea to colonize the islands off the coast of Florida.