I made the trip from Cape May to Rhode Island, and sailed past Block Island, about 2 years ago. We actually saw a couple logs in the water back then. However; the biggest danger was from all the fishing boats. Those people are focused on their business, and not on other vessels so much. We were almost run down about 2am off New York. We tangled with another fishing boat near Block Island, as well as a tug towing barges.
Keep a look out round the clock, and stay well clear of fishing boats dragging nets or lines.
On the other hand; we saw lots of dolphins, turtles and whales.