I have a textbook which describes various considerations colonists made in selecting sights for settlements. For example, it says that Jamestown was too swampy, so there were many mosquitoes and diseases and the water was not suitable for drinking. Among the various considerations, it says that settlers avoided placing their colonies near the coastline, because this would increase the danger of being attacked from the sea. Prior to 1730, were there any actual situations in which a colony, being near the ocean, was attacked from the sea? Did coastal locations benefit from being easier to defend against attacks carried over land?
Here's one example: The dutch colony of New Amsterdam (on Manhattan Island, it's New York now) was captured by four English frigates sailing into its harbour.
The British are on the other side of this one, but the point stands. Here's one out of the time scale but the Battle of Nassau deserves a mention as the US marines' first amphibious landing.