What knowledge would contribute to survival in the early colonies?

Like any venture into unknown lands, the ability to provide food and potable water to one's self and companions is very important.  The settlers of Jamestown learned this the hard way as the gentleman farmers knew little about the actual production of food and they settled next to the brackish James River that was so crowded with mosquitoes that not even the native Americans would live there for any period of time.  One also had to have the ability to build a shelter--this was a priority with the Pilgrims who came to Plymouth late in the year and who needed to protect themselves from the Northeastern winter.  Finally, one had to be able to make peace and negotiate with the native Americans.  Both the settlers at Jamestown and Plymouth had to make alliances and trade networks with native tribes for their survival.  Both groups did this with varying degrees of success, but ultimately through disease and war they ended up dominating the local tribes.