SYDNEY — Nine beaches in Sydney, including well-known Manly beach, were closed to bathers on Tuesday after small white and gray balls of debris washed up on the shores at the height of the summer holiday season. Northern Beaches Council said it was working on safely removing the matter. Most of the samples of the ball-shaped debris were the size of marbles, with some larger, it said in a statement. Sydney’s ocean beaches, famed for golden sand and clean water, draw tourists from around the globe. Beachgoers were advised to avoid Manly, Dee Why, Long Reef, Queenscliff, Freshwater, North and