The time series for net fishery and retained rod catch runs from 1952 to the most recently published season. The time series for released rod catch runs from 1994 to the most recently published season. The data are the summations of reports from individual fisheries. No attempt has been made to correct for non-returns or incomplete information held in the register of proprietors and occupiers.
Data files for the net fisheries contain effort data. Fixed engine effort is summarised as median number of traps operated within a given district in any month. Net and coble effort is summarised as median number of crews operated within a given district in any month. We have no comprehensive time series of fishing effort information associated with the rod & line fishery.
Reported catches are provided at the finest geographical (salmon fishery district) and time (month) scales consistently available. Salmon fishery districts correspond either to a single river catchment together with adjacent coast or to groups of neighbouring river catchments and associated coastline. Salmon fishery districts may be further aggregated into salmon fishery regions whose extents are described in Collecting the Marine Scotland Salmon and Sea Trout Fishery Statistics and Scottish Marine Regions which correspond to those identified in Scottish Government’s National Marine Plan. Salmon Fishery Districts are included in the Scottish Marine Regions as indicated below:

Forth & Tay: Tweed to North Esk
North East: Bervie to Ugie
Moray Firth: Deveron to Wick
North Coast: Thurso to Grudie
West Highlands: Inchard to Leven
Argyll: Creran to Ormsary
Clyde: Carradale to Stinchar
Solway: Luce to Annan
Outer Hebrides: Loch Roag to Howmore
Orkney Islands: Orkney
Shetland Isles: Shetland

Salmon fishery districts are characterised by Name, District ID and Report Order. Ordering the data with respect to “Report Order” sorts the Districts spatially. Districts are ordered counter-clockwise starting with the Tweed as Report Order 1.
The categories by which sea trout data have been reported have varied through the time series (Collecting the Marine Scotland Salmon and Sea Trout Fishery Statistics). Finnock catches have been reported since 2004. Finnock are sea trout which have spent less than a year at sea and making their first return to fresh water. They may also be known as whitling or herling.
Catches of farmed salmon and grilse have been reported since 1994.