The eastern diamondback rattlesnake (Crotalus adamanteus) is a species of venomous pit vipers, found in southeastern United States of America. It is the largest rattlesnake, longest and the heaviest venomous snake in the Americas. There are currently no subspecies found.

Description
The eastern diamondback rattlesnake is the heaviest venomous snake in the Americas, and the largest rattlesnake. The heaviest eastern diamondback rattlesnake ever found weighed 15.4 kg (34 Ib), and was 7.8 ft (2.4 m) long. This eastern diamondback rattlesnake however, was not the longest ever found, for there have been reports on seeing some which were 8 feet long. An eastern diamondback rattlesnake's actual length is usually around 3 to 5 feet long. They usually weigh 2.3 kg (5.1 Ib), but some that have been found can weigh 5.12 kg (11.3 Ib), or even 6.7 kg (15 Ib). They usually are brown, brownish yellow, brownish gray, or olive ground in color. There skin is covered with 24-35 dark brown or black diamond-shaped blotches, which have a lighter center. The belly is yellow or cream in color.
 thumb|left | 200px |The head of an eastern diamondback rattlesnake

Common names
The eastern diamondback rattlesnake is also called the "diamond snake", the "common rattlesnake", the "diamond rattler", the "Florida diamondback snake", the "lozenge-spotted rattlesnake", the "southern woodland rattler", and the "water rattler".

Distribution and Habitat
They live in dry pine forests, salt marshes, swamp forests, and cypress swamps of United States of America. The U.S.A's states which it lives in are southeastern North Carolina, Georgia, Florida, southern Alabama, Mississippi, southeastern Louisiana and North Carolina.

Behavior
Like most rattlesnakes they live on land, and are not good climbers. They have, however, been reports on some eastern diamondback rattlesnake being in bushes and trees, probably looking for a prey. Even though they are not good climbers, they are very good swimmers. These rattlesnakes have been seen many times hiding in mammal burrows. hawks, eagles, and other snakes eat eastern diamondback rattlesnakes.

Diet
The eastern diamondback rattlesnake catches its prey by ambushing it. It eats small mammals like rabbits and rats, birds and sometimes lizards. Since of adults large size they can easily attack and eat adult rabbits, there have also been reports on some eating  turkeys. Young eastern diamondback rattlesnake eat mainly small rodents like mice, rats and squirrels. Sometimes they also eat large insects.

Reproduction
The eastern diamondback rattlesnake, like all rattlesnakes, are ovoviviparous. A female is pregnant for around five to six months before giving birth to her young. The young stay with their mother for a few hours (up to a few days at most) before leaving on their own to go and hunt for food. Because of this, many of the young snakes die quickly. Females give birth to around 7 to 21 young at a time; they give birth to their young in July to early October. Young are born to be about 12 inches (30 cm) long. When they are born they look similar to adults, but have a small button on their tail, unlike adults who have rattles on their tail.

Conservation status 
It is classified as Least Concern on the IUCN Red List. In North Carolina, the eastern diamondback rattlesnake is protected by state law. It is considered endangered inside the state. It may be extinct in Louisiana. Some scientists and conservationists believe it may even be extinct in North Carolina.

This species is currently surveyed for being added to the Endangered Species List by the United States Fish and Wildlife Service because of its recent decrease in number.

Venom 
The eastern diamondback rattlesnake is the most dangerous venomous snake in North America. While not usually aggressive, it is large and powerful. Its bite has a mortality rate of 10–20% when untreated. The estimated human lethal dose is 100–150 mg. A doctor described one case in which the symptoms included pain, bleeding from where the snake bit the person, internal pain, bleeding from the mouth, hypotension, a weak pulse, swelling and discoloration of the limb that was bitten.

CroFab and Wyeth's ACP are great antivenoms against bites from this type of rattlesnake. But, big doses may be needed to manage really bad cases of envenomation.

References 

Vipers