It is similar in function to Fishing Boats in previous Age of Empires games, but can also fish for Coin (from Whales, which are infinite). It can also garrison units (by the use of the garrison button).
Although it lacks offensive or defensive capabilities, it can be garrisoned inside the Dock and deal damage to enemy units within range (similar to Villagers in a Town Center).
"Fishing was a huge industry in northeastern North America, where poor soil did not readily support extensive agriculture. Fish and shellfish were abundant in the waters of the Atlantic and in time a thriving industry of fishing, whaling and shipbuilding developed. The Gloucester Schooner was a long, sleek, two-masted fishing vessel first constructed in 1713 in Gloucester, Massachusetts. These ships plied the waters of the Atlantic for cod, halibut, and mackerel, sometimes salting their catches at sea or, when close to the coast, bringing them in fresh."