No Sunday Fishing ruling covering Scotland as a whole goes back many many years and was believed to have been implemented for two reasons.
Firstly -to satisfy the demands of the Church the Sabbath being a day of rest.
Secondly-to allow the free passage of running fish from estuary to freshwater
ie: no netting.
...and to allow fish to run without any harassment from anglers.
Most fishery owners/clubs/estates do not permit any Sunday fishings at all especially if there are migratory fish present.
Some simply uphold the 'Church's' wishes and do not allow Sunday fishing at all even if that particular water holds no salmon or sea trout.
These restrictions have been in force for so long that I believe they will remain with us for a very long time to come.
Personally I'm happy to leave the water alone on a Sunday-Salmon have such an ardous journey to reach their reach their birth river and then face many other unseen dangers in freshwater that Yes show some respect and them one day without any harassment !!
Kindest regards
John
ghillie/salmon/seatrout/flies/water/cast/tackle/skate/countryside/play/