Unlock the containers where Captain Shandy stashed her treasures in and loot some bleached crossbones. The crossbones bind-on-take, decay after about 2,500 Alyrian minutes, and they must be used in the same room Captain Shandy is in.
For your seamanship and protecting Alyria from the dread pirates, the Powers granted thee a Mark. You have gained the Mark of Seamanship! You gain 48 practices! You gain 400 archon points!