COROLLA, N.C. (AP) -- A study is being launched to determine what impact wild horses have on the northern Outer Banks of North Carolina, where the animals increasingly compete with visitors for space.

The Virginian-Pilot of Norfolk reports Monday that the Corolla Wild Horse Fund estimates the study could cost $800,000 and take up to two years.

Fund official Karen McCalpin said the group plans to commission researchers from North Carolina State University to examine effects the horse herd has on marshes and grass.

The fund and the Currituck National Wildlife Refuge agreed in 1999 to limit the herd to about 60 horses. The herd currently numbers 101.

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