SWAMPSCOTT – A Swampscott native was found dead floating off Pickering Wharf in Salem shortly before 8 a.m. Monday, according to police.The body was identified as Jocelyn Callahan, 25, who most recently lived in Salem and was a 2001 graduate of Swampscott High School.Authorities said foul play was not suspected in her death.According to Callahan’s MySpace.com page, she most recently worked as a cook for the Gulu-Gulu Café in Salem. She was also a student at the New England Hair Academy in Malden.Friends began leaving good-bye messages on her MySpace page Monday night.