By: Samantha Bartlett
Tick-borne diseases have doubled in the last decade and the lone star tick is a vector of several of these diseases. The lone star tick (Ambylomma americanum) has long been known for its role as a nuisance pest and as a vector of human pathogens. The female of this species is easily identified by the single white spot on its back. Lone star ticks are associated with several diseases including tularemia, ehrlichiosis, Heartland virus, southern tick-associated rash illness (STARI) and alpha-gal syndrome (red meat allergy). The lone star tick is known as an aggressive tick in that it actively hunts down its host prey. Lone star ticks feed on large mammals, but predominately white-tailed deer. The larvae and nymphs of this species also feed on birds.
Historically the range of lone star ticks has been restricted to southern states with some populations extending as far north as southern New Jersey. Recently however, due to changes in climate and seasonal activity, the range of the lone star tick has increased further into northeastern and Midwest states. Breeding populations of lone star ticks have been documented in Massachusetts, Connecticut, Rhode Island, and New York. Lone star ticks have also been reported as far west as Oklahoma, Kansas, Nebraska and South Dakota.
Preferred requirements to attract populations of lone star ticks include specific humidity ranges and the presence of invasive plants. White-tailed deer are frequently attracted by invasive plants. Another factor leading to expansion of the species is their willingness to travel large distances in search of the perfect host.
Current climate conditions may already be suitable for establishment of these populations in southern Canada. While climate change would appear to be the driving force behind this northward expansion, scientists have revealed that the populations of lone star ticks in New York and Oklahoma are genetically different from the lone star tick populations in the normal historical range.
Ecological niche predictive models were used to determine potential expansion ranges for lone star ticks. These models show an even greater future expansion of tick populations through the Midwest and northern states in addition to the west coast of the United States and Mexico.
