The study will be conducted by the United States Fish and Wildlife Service and North Carolina State University.
The horses are a popular tourist attraction in the area and sometimes leave the forested areas to spend time on the beaches.
The researchers will explore the affects of grazing mammals - horses, feral pigs and deer - on the maritime forests, marshland and wet meadows within the study area by monitoring enclosures in which each of the species has been excluded.
One fenced area, which has already been developed, excludes all three species.
The current wild-horse herd count is around 100 - 40 more than the number stated in a 1999 management plan.
The Corolla Wild Horse Fund, set up 1989 by concerned citizens to heighten awareness about the presence of the coast-dwelling wild horses in the area, is growing increasingly concerned about maintaining genetic diversity in the herd.
It unsuccessfully petitioned the Fish and Wildlife Service last year to increase the herd size further to at least 120 to boost the gene pool.