There are mangroves and then there are mangroves. My old hurricane hole in the Florida Bay off Tarpon Basin had black mangroves with three-foot thick trunks and a 50' canopy. I tied up with 500' of 7/8 nylon and used 5/8 anchor lines for spring lines (38', 7 ton mono with 58' mast). The creek was about 40' wide and ten feet deep with room for 5 boats nose to tail. During the ten years I was there, we had over 100 days with 100 knot gusts or better, and more than 20 cat two or better hurricanes. Most of those 100 wind events were just random, unnamed, unforecast events, so everyone stayed pretty well prepared all the time. When you can climb 20 feet up into the mangroves and tie off to a foot thick branch and know it's not going under water in a 16' surge, mangroves work pretty good. I've had to clean a six-foot deep pile of debris off my boat, but it was safe and dry underneath, and nothing could come adrift.