Officials say a stingray invasion prompted warnings for beachgoers along the Alabama coast. Purple flags are flying on beaches because of a large number of stingray sightings, and more than 20 people have complained about coming into contact with them. The beach safety director in Orange Beach, Melvin Shepard, tells WALA-TV (http://bit.ly/14CyMSR ) several people have been stung. Stingrays get their name from a barb in their tail, which they swing as a defense mechanism. The barb can hit anyone walking in the water on the lower leg.