Assateague horses get the stamp treatment

A horse grazes on Assateague Island on the morning of Feb. 11, 2016.

Johnny's Star, center, is seen grazing on Assateague Island in this 2014 image.

Ponies graze on the grass near the entrance to Assateague Island National Park. Ponies, like other flora and fauna, have adapted to the harsh environment of a barrier island.

Karen McLain is interrupted while painting the wild horses of Assateague on Tuesday morning.

Wild horses at Assateague that are possible subjects for painter Karen McLain on Tuesday morning.

Wild horses at Assateague that are possible subjects for painter Karen McLain on Tuesday morning.

Wild horses at Assateague that arepossible subjects for painter Karen McLain on Tuesday morning.