This is pretty normal behavior especially since the swan and the geese are probably young offspring from this past year that the parent's have chased from the nesting habitat to find a habitat of their own. Since the young birds have not paired yet, they are happy to have some pals to hang around the pond. This behavior may or may not continue once the young birds come of age, find a mate and their hormone levels increase during the nesting/mating season. In any case, enjoy while you can. The Regal Swan