Timber Rattlesnakes Control the Spread of Lyme Disease

A new finding by a team of biologists from the University of Maryland has shown that timber rattlesnakes indirectly benefit human health by controlling the spread of Lyme disease that causes neurological problems.

Timber rattlesnake (Crotalus horridus), a species of venomous pit viper and the most dangerous snake in North America, indirectly benefits humankind by checking the spread of Lyme disease. Through this finding the researchers highlight the importance of conserving all species.

Lyme disease is a bacterial infection that is transmitted through the bite of a particular type of tick. They feed on infected mice and other small mammals. But some animals such as foxes and other mammal predators help control the disease by curbing the population of the small mammals. A drop in the mammal predators can lead to a rise in Lyme disease in humans.

Lyme disease if not treated on time can lead to arthritis, it can affect the nervous system causing headache, paralysis of facial muscles and memory loss. One out of ten Lyme disease patients develops heart problems.

The timber rattlesnake is found in northeastern United States. The former University of Maryland graduate student Edward Kabay, through this study wanted to check whether rattlers also play a role in keeping Lyme disease in check.

Kabay based his finding on previously published studies that focused on the diet of the timber rattlers in four different sites in the Eastern forest. He wanted to check the number of small mammals the snakes consumed and then cross check that with the data on the average number of ticks each small mammal carried.

The numbers showed that annually each timber rattler removed 2,500-4,500 ticks from each site.

Timber rattlesnake is listed as an endangered species in six states and threatened in five states under the Endangered Species Act.

"Habitat loss, road kills, and people killing them out of fear are the big issues," said University of Maryland Associate Biology Prof. Karen Lips. "They are non-aggressive and rarely bite unless provoked or stepped upon."

The teams finding will be presented at the annual conference of the Ecological Society of America.