With all of the rain that you have had this year, the swans may be competing for a safe habitat for their young with good food resources. If you can kayak from a distant shore or avoid their area during the next several weeks, the swans should calm. The swans are right in the middle of nesting season and the inclement weather did not help as far as ideal nesting, feeding and molting areas. If the swans become too defensive, you might contact Swan Lifeline in Eton. They may be able to intervene so that the swans and the kayakers can coexist during the nesting season. The Regal Swan