ATLANTIC_CH07_Specification_1 / Area where bottom habitat has been disturbed by bottom trawling (number of disturbances per month)

Data from a number of different sources have been integrated to provide new perspectives on fishing activities. Vessel Monitoring Systems (VMS) record and transmit the position and speed of fishing vessels at intervals of two hours or less. Fishing time can be calculated from the VMS data and combining this parameter with vessel logbook data, maps of fishing effort and intensity at different spatial and temporal scales can be calculated. The statistical software package “R” is used to extract the required information then re-interrogated to produce maps of fishing effort or intensity per month and year. The use of Automatic Identification System (AIS) data was not considered as combining AIS data with fisheries logbook data would pose issues namely; the ability of the AIS system to be switched off, only mandatory on vessels > 15 meters in length, cost involved to purchase data, and confidentiality.