The largest source of wealth for Plymouth Colony was the fur trade. The disruption of this trade caused by Myles Standish's raid at Wessagussett created great hardship for the colonists for many years and was directly cited by William Bradford as a contributing factor to the economic difficulties in their early years. The colonists attempted to supplement their income by fishing; the waters in Cape Cod bay were known to be excellent fisheries. However, they lacked any skill in this area, and it did little to relieve their economic hardship. The colony traded throughout the region, establishing trading posts as far away as Penobscot, Maine. They were also frequent trading partners with the Dutch at New Amsterdam.