I'll be paddling the Shumagin Islands out of Sand Point for sixteen days in July. Never been before, but I've read the account posted with Maine Island Kayak Company. I've used google earth to check out potential landing/ camping sites, but am perplexed by what look like boulder-covered beaches on the northern end of Nagai Island around Northeast bight. Can anyone tell me what's covering those beaches? N 55degrees13.5 minutes/ W 159 degrees 54.5 minutes.