Assateague Island, Virginia, is known for its population of wild horses, which every year are rounded up and brought across the channel to Chincoteague Island, where some are auctioned off to keep the numbers under control. But in order to get there, they have to swim, so the Chincoteague Wild Pony Swim enlists the help of the Coast Guard to keep the horses safe. Several 24-foot Special Purpose Craft-Shallow Water boat crews from Station Chincoteague maintained a safety perimeter from other boats and people as they swam the channel, with thousands of spectators looking on Wednesday. The tradition dates back…