Hello,
My wife and I have been going to St Croix for over 20 years. Depending on the time of year that you are going you can see all sorts and sizes of life. Right now the local shops are seeing and hearing whales; just offshore. Many of the local dives can be done from the beach and those that can not are very close shore, so they are short boat ride away.
Generaly I would not recomend a live aboard there. There are a number of great local shops. You can find housing from very nice 4 star resorts to simple cottages and condos. There is just so much on the island to do that I would not limit myself to a live aboard (ymmv). If you give me an idea of when you are looking to go I’d be happy to answer any questions that I can.
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