The Kinsale fishery only started c.1860 with a few boats going out in March - before this the Manx herring fishery was inshore only and would not have been away on a Sunday evening at this time - thus none are missing from earlier censuses
see http://www.ee.surrey.ac.uk/Contrib/manx/fulltext/ws1923/p001.htm for a brief history of Irish sea fishing - the Kinsale fishery was started by a Peel Boat owner hence the majority were Peel based.

In 1881 the fleet sailed on the tide on the Monday of the census night (Sun/Mon) hence the confusion - see my census page
http://www.ee.surrey.ac.uk/Contrib/manx/famhist/genealgy/census.htm