Parameter	Number of bits	Description 
MessageID	6	AIS message number.  Must be 8
RepeatIndicator	2	Indicated how many times a message has been repeated
UserID	30	Unique ship identification number (MMSI)
Spare	2	Reserved for definition by a regional authority.
dac	10	Designated Area Code - 366 for the United States
fid	6	Functional IDentifier - 63 for the Whale Notice
efid	12	Extended Functional IDentifier.  1 for the Whale Notice (dac+fid+efid defines the exact message type)
numreports	2	Number of detection reports filled out in this message
stationid1	8	Identifier of the station that recorded the whale.  Usually a number.
time1_day	5	Time of most recent whale detection.  UTC day of the month 1..31
time1_hour	5	Time of most recent whale detection.  UTC hours 0..23
time1_min	6	Time of most recent whale detection.  UTC minutes
center1_longitude	28	Center of the detection zone.  East West location
center1_latitude	27	Center of the detection zone.  North South location
timetoexpire1	16	Seconds from the detection time until the notice expires
radius1	16	Distance from center of detection zone (lat/lon above)
stationid2	8	Identifier of the station that recorded the whale.  Usually a number.
time2_day	5	Time of most recent whale detection.  UTC day of the month 1..31
time2_hour	5	Time of most recent whale detection.  UTC hours 0..23
time2_min	6	Time of most recent whale detection.  UTC minutes
center2_longitude	28	Center of the detection zone.  East West location
center2_latitude	27	Center of the detection zone.  North South location
timetoexpire2	16	Seconds from the detection time until the notice expires
radius2	16	Distance from center of detection zone (lat/lon above)
stationid3	8	Identifier of the station that recorded the whale.  Usually a number.
time3_day	5	Time of most recent whale detection.  UTC day of the month 1..31
time3_hour	5	Time of most recent whale detection.  UTC hours 0..23
time3_min	6	Time of most recent whale detection.  UTC minutes
center3_longitude	28	Center of the detection zone.  East West location
center3_latitude	27	Center of the detection zone.  North South location
timetoexpire3	16	Seconds from the detection time until the notice expires
radius3	16	Distance from center of detection zone (lat/lon above)
Spare2	21	Not used.  Should be set to zero.
Total bits	424	Appears to take 2 slots