Large numbers of Portuguese man-of-wars were found washed up on the south shore of the Vineyard this week, prompting The Trustees of Reservations to post notices at Norton Point beach in Edgartown. “We are going to be putting up signage warning people they are back,” said Chris Kennedy, Vineyard superintendent for the Trustees, who manage and own a long stretch of south-facing shoreline from Norton Point to Wasque Reservation. “We are finding them primarily on the south side, but it will not be unusual to find them at East Beach too,” Mr. Kennedy said. He said it is early to find man-of-wars, which ordinarily wash up on beaches in the warmer months.