Beavers are biologically built to detest the sound of running water. If water is running, they will dam it until it pools, dammit.
The best way to prevent beaver activity on your property is to make sure that the trees are adequately protected. As you can see here, beavers can be quite tall, and they can be active on top of the snow, giving them a few feet of lift in the winter. Our best suggestion is hardware cloth (galvanized metal screening) all the way around the trees, ensuring that the protective barrier can be loosened every few years as the trees grow.
If there is a dam on your property, it can be very difficult to manage while the beavers are still active. You will likely enter into an eternal game of taking the dam out only to find they've rebuilt the next time you go to the cottage.
Additional to dams, beavers construct feed beds where they stockpile logs for use in the winter once the ice forms. Loose logs and twigs are likely feed beds and may not be replaced if moved.
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