Application Identifier 7009 indicates fishing gear.
This shall be indicated by the fishing vessel which caught the fish. The fishing gear is defined by the Food and Agriculture Organization of the United Nations (FAO), and is used to identify the type of fishing gear used to catch the fish. This list can be accessed via:
http://www.fao.org/fishery/cwp/handbook/M/en
Example:
01.1.1 (one boat operated purse seines)
03.1.1 (beam trawls)
AI 7009 must always be entered together with a GTIN.