War with France and Scotland existed in 1560, and this state of affairs caused a list of vessels to be drawn up at that time. The return for Essex gave 565 mariners and sailors, although possibly only those who were ashore at the time were counted. The distinction between mariners and sailors is also unclear.
The next report was compiled in 1564-5, and Essex was described as having 187 harbours, ports and creeks; 349 ships, vessels, and boats, together with 1,196 mariners and fishermen. As can be seen in this first table, Wivenhoe was considered quite a sizeable port at that time.
A later survey was conducted by Thomas Colshill in 1572, surveyor of customs at London. The analysis of available vessels and their sizes is shown in this table:
Source: A History of Essex – page 276