This can be a big issue or not an issue at all depending on where you do your boating, but anywhere there’s marine life on the bottom, boats and especially anchors can have dramatic impacts.
In some areas (such as on Florida’s coral reefs) it’s actually illegal to anchor because of the damage it can do to the corals. But anchoring isn’t the only issue. Boats can rip “prop scars” in shallow weed beds, churn muddy bottoms and cause cloudy water, and disturb shellfish beds.
Study up on the waters you rove, to make sure you’re being kind to the benthic brethren that live there.